Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Ethnopharmacol ; 334: 118528, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972526

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Pudilan Xiaoyan Oral Liquid (PDL) is a proprietary Chinese medicinal preparation approved by the State for treating acute pharyngitis in both adults and children (Approval No. Z20030095). It is worth noting that children exhibit unique physiopathological characteristics compared to adults. However, the in vivo regulatory characteristics of PDL in treating acute pharyngitis in children remain incompletely understood. AIM OF THE STUDY: The differential absorption and metabolism characteristics of the main pharmacological components in PDL in young and adult rats were investigated with a view to providing a reference for preclinical data of PDL in medication for children. MATERIALS AND METHODS: This study utilized UPLC-Q-TOF-MS to investigate the pharmacodynamic material basis of PDL. The focus was on the gastrointestinal digestion and absorption characteristics of organic acid components in PDL (PDL-OAC), known as the primary pharmacodynamic components in this formulation. The research combined in vitro dynamic simulation and a Quadruple single-pass intestinal perfusion model to examine these characteristics. The permeability properties of PDL-OAC were evaluated using an artificial parallel membrane model. Additionally, an acute pharyngitis model was established to evaluate the histopathological condition of the pharynx in young rats using H&E staining. The levels of IL-1ß, TNF-α, IL-6, and IL-10 in blood and pharyngeal tissue homogenates of young rats were quantified using ELISA kits. RESULTS: A total of 91 components were identified in PDL, including 33 organic acids, 24 flavonoids, 14 alkaloids, 5 terpenoids and coumarins, 3 sugars, and 12 amino acids. The PDL-OAC exhibited a significant reduction in IL-1ß, TNF-α, IL-6, and IL-10 levels in the pharyngeal tissues of young rats with acute pharyngitis. Results from dynamic simulation studies of gastrointestinal fluids revealed that the PDL-OAC (Specifically chlorogenic acid (CGA), gallic acid (GA), chicoric acid (CRA), and caffeic acid (CA)) were effectively stabilized in the gastrointestinal fluids of both children and adults in vitro. Young rats, characterized by thinner intestinal walls and higher permeability, efficiently absorbed the four organic acids across the entire intestinal segment. The absorption of CGA, GA, and CRA followed a concentration-dependent pattern, with CGA and GA absorption being influenced by exocytosis. CONCLUSION: The efficacy of the PDL-OAC in treating acute pharyngitis was demonstrated in young rats. The absorption rate of these components was observed to be faster in young rats compared to adult rats, underscoring the need for dedicated studies on the drug's usage in children. This research provides valuable insights for the appropriate clinical use of PDL in pediatric patients.

2.
Sensors (Basel) ; 24(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38931812

RESUMO

In this study, we have developed an electrostatically suspended accelerometer (ESA) specifically designed for ground use. To ensure sufficient overload capacity and minimize noise resulting from high suspension voltage, we introduced a proof mass design featuring a hollow, thin-walled cylinder with a thin flange fixed at the center, offering the highest surface-area-to-mass ratio compared to various typical proof mass structures. Preload voltage is directly applied to the proof mass via a golden wire, effectively reducing the maximum supply voltage for suspension. The arrangement of suspension electrodes, offering five degrees of freedom and minimizing cross-talk, was designed to prioritize simplicity and maximize the utilization of electrode area for suspension purposes. The displacement detection and electrostatic suspension force were accurately modeled based on the structure. A controller incorporating an inverse winding mechanism was developed and simulated using Simulink. The simulation results unequivocally demonstrate the successful completion of the stable initial levitation process and suspension under ±1g overload.

3.
Materials (Basel) ; 17(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38473511

RESUMO

Strand electromagnetic stirring (S-EMS), a technique applied in the secondary cooling zone, enhances the solidification structure of casting slabs. This study examines how the arrangement pattern of electromagnetic stirring rollers-face-to-face, side-to-side or up-down misalignment produces this enhancement. It uses simulations to analyze the electromagnetic field distribution in these configurations. The findings demonstrate that: (1) The magnetic flux density distribution in the casting slab is related to the arrangement pattern of the electromagnetic stirring rollers. (2) The face-to-face arrangement produces the largest and most concentrated electromagnetic force compared to the other two arrangement patterns. (3) S-EMS can effectively improve the equiaxed grain ratio of casting slabs. Before and after EMS is turned on, casting slabs' average equiaxed grain ratio goes up from 8% to 33%.

4.
Materials (Basel) ; 17(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276421

RESUMO

The heat transfer of a slab is significantly influenced by roll contact during the continuous casting process. The influence of roll contact calculation methods on the predicted heat transfer results has not been previously investigated. In this work, the non-uniform solidification of the wide-thick slab was studied with a 2D heat transfer model using real roll contact method (R. method) and equivalent roll contact method (E. method). The predicted slab surface temperature and shell thickness were verified with the measured results of the infrared camera and nail shooting experiments, respectively. Then, the predicted heat transfer results (including the slab surface temperature, mushy region length, and solidification end position) for the wide-thick slab with different thicknesses and different casting speeds were calculated using the E. method and R. method, and the influence of these two roll contact methods on the predicted heat transfer results was discussed for the first time. The results show that both these two roll contact methods could be applied to accurately predict the slab surface temperature without considering the transient temperature dips in the roll-slab contact regions. However, the deviation of the predicted mushy region length and solidification end position using the E. method are obvious. Compared with the R. method, the predicted mushy region length obtained using the E. method is larger and the solidification end obviously subsequently moves along the casting direction.

5.
Cancer Res ; 83(8): 1249-1263, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-36715635

RESUMO

Angiogenesis is vital for tumor growth and metastasis. Emerging evidence suggests that metabolic reprogramming in endothelial cells (EC) may affect angiogenesis. Here, we showed that multiple regulators in the fructose metabolism pathway, especially fructose transporter SLC2A5 and fructose-metabolizing enzyme ketohexokinase (KHK), were upregulated in tumor endothelial cells from hepatocellular carcinoma (HCC). In mouse models with hepatoma xenografts or with Myc/sgp53-induced liver cancer, dietary fructose enhanced tumor angiogenesis, tumor growth, and metastasis, which could be attenuated by treatment with an inhibitor of SLC2A5. Furthermore, vessel growth was substantially increased in fructose-containing Matrigel compared with PBS-Matrigel. Inhibiting fructose metabolism in EC cells in vivo using EC-targeted nanoparticles loaded with siRNA against KHK significantly abolished fructose-induced tumor angiogenesis. Fructose treatment promoted the proliferation, migration, and tube formation of ECs and stimulated mitochondrial respiration and ATP production. Elevated fructose metabolism activated AMPK to fuel mitochondrial respiration, resulting in enhanced EC migration. Fructose metabolism was increased under hypoxic conditions as a result of HIF1α-mediated upregulation of multiple genes in the fructose metabolism pathway. These findings highlight the significance of fructose metabolism in ECs for promoting tumor angiogenesis. Restricting fructose intake or targeting fructose metabolism is a potential strategy to reduce angiogenesis and suppress tumor growth. SIGNIFICANCE: Fructose metabolism in endothelial cells fuels mitochondrial respiration to stimulate tumor angiogenesis, revealing fructose metabolism as a therapeutic target and fructose restriction as a dietary intervention for treating cancer.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Células Endoteliais/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Neovascularização Patológica/tratamento farmacológico , Frutose , Transportador de Glucose Tipo 5
6.
Zhongguo Zhong Yao Za Zhi ; 47(21): 5708-5716, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-36471989

RESUMO

There are many kinds of pharmaceutical preparations for children in China, which are generally divided into oral solid preparations and oral liquid preparations. Solid preparations, such as microtablets, pellets, dispersible tablets, and fine granules, have become the development trend of pediatric drugs. Liquid preparations mainly include syrup, suspension, oral solution, and drops. The poor taste and the treatment of drugs in children of different ages are the key factors affecting the efficacy, safety, and compliance of pediatric drugs. To reduce the risk caused by the fluctuation of blood concentration and improve the oral compliance of pediatric drugs, it is urgent to develop new techniques for granulation and flavor maskingto improve the poor taste of solid preparations. For liquid pre-parations with poor taste, the flavor correction technique should be used. This paper summarized the new pharmaceutical techniques for granulation and flavor masking, and it was found that sustained/controlled-releasegranules, fine granules, and chewing solid mini-tablets became the mainstream of oral solid preparations for children. Generally, multiparticle preparation, coating, microencapsulation, and other granulating techniques were involved in these preparations. Granulation and flavor masking are closely related and synergetic. Flavor masking techniques mask the bitter taste of Chinese medicine from four aspects, including confusing the brain taste, changing the compounds, reducing the exposure of bitter molecules to bitter receptors in the mouth, and numbing the taste cells to increase the threshold of bitter perception. At present, the main drugs for children on the market mainly inhibit the oral release of bitter drugs.


Assuntos
Química Farmacêutica , Paladar , Criança , Humanos , Química Farmacêutica/métodos , Administração Oral , Comprimidos , China
7.
Sci Adv ; 8(18): eabo0375, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35507666

RESUMO

The real-time, in-line analysis of light polarization is critical in optical networks, currently suffering from complex systems with numerous bulky opto-electro-mechanical elements tandemly arranged along the optical path. Here, we design and fabricate a fiber-integrated polarimeter by vertically stacking three photodetection units based on six-layer van der Waals materials, including one bismuth selenide (Bi2Se3) layer for power calibration, two twisted black phosphorus (BP) layers for polarization detection, and three hexagonal boron nitride (hBN) layers for encapsulation. The self-power-calibrated, self-driven, and unambiguous detection of both linearly polarized (LP) and circularly polarized (CP) light is realized by the broken symmetry-induced linear photogalvanic effects (LPGEs) and circular photogalvanic effects (CPGEs) in the two BP units. Moreover, the device enables single-pixel polarimetric imaging to acquire spatial polarization information. The ultracompact device structure, free from external optical and mechanical modules, may inspire the development of miniaturized optical and optoelectronic systems.

8.
Opt Express ; 30(5): 6818-6825, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35299460

RESUMO

In this work, we design and fabricate a compact photoelectrochemical (PEC) sensor by integrating a graphene-MoS2 heterostructure on an optical fiber tip. The graphene serves as a transparent carrier transport layer, and the MoS2 presents a photoelectrical transducer that generates photocarriers and interacts with ascorbic acid (AA) in solution. This device is used to demonstrate a self-powered detection of AA with a concentration range between 1 mM and 50 mM, and a time response of ∼ 6 ms. The device downsizes traditional PEC systems to the micrometer scale, benefiting the real-time monitoring of biochemical changes in small areas and opening the pathway for miniaturized PEC sensing applications.


Assuntos
Técnicas Biossensoriais , Grafite , Grafite/química , Fibras Ópticas
9.
Analyst ; 147(8): 1631-1640, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35302559

RESUMO

Mycoplasma ovipneumoniae (MO), a disease-causing pathogen with some of the highest levels of morbidity and mortality, can spread silently at the herd level. A novel alternative nanoprobe for MO was prepared using porous metal-organic frameworks (MOFs) as the scaffold and hairpin DNA with specific sequences of MO and G4 segments as the probe. This preparation was based on the strong fluorescence emission by ThT (thioflavin T) in the limitation of G-quadruplexes with a cavity structure. The use of MOFs effectively limited the folding behavior of G4 as a part of the probe to improve the defect of the strong background signal caused by the free-state G4Probe in a buffer. The results from the selectivity experiment showed that only a trace amount of the target with lower ΔG could be the "key" to the highly efficient triggering of the release behavior of the G4Probe from MOFs and the subsequent change in the fluorescence behavior of ThT. The DNA targets could be determined by observing the change in the signal. More importantly, the probe showed a low detection limit and a good linear correlation between the concentration of target DNA ranging from 10-10 M to 10-6 M not only in buffer but also in natural complex media. Moreover, the operation involved in the whole strategy was simple and the total cost was low. These findings demonstrated the value of the probe in further clinical diagnosis. This study reports the successful construction of a ΔG-sensitive sensor for MO for the first time.


Assuntos
Técnicas Biossensoriais , Quadruplex G , Mycoplasma ovipneumoniae , Benzotiazóis/química , Técnicas Biossensoriais/métodos , DNA/química , DNA/genética , Fluorescência , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos
10.
Analyst ; 147(2): 282-292, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34901972

RESUMO

Biofouling is a nuisance in the practical applications of biosensors, which seriously affects the reliability and accuracy of detection. The utilization of antifouling interface materials is a promising option for mitigating biofouling. Only highly accumulated antifouling polymeric surfaces tend to offer "zero" nonspecific protein adsorption. Herein, superior antifouling coatings based on chondroitin sulfate (CS) were prepared by the NH2-MIL-53 (Al) assisted strategy. This is a novel design to improve the antifouling property of material by taking advantage of the high specific surface area of the three-dimensional MOF to increase the accumulation degree of antifouling functional groups per unit area. And the related chemical technology is simple and easy to operate. As expected, this novel CS-loaded MOF demonstrated an excellent antifouling performance in various biological samples, even in 100% goat serum. Only 8.48% changes of differential pulse voltammetry (DPV) were found. Furthermore, this antifouling interface material is successfully applied for the specific detection of the tuberculosis (TB) gene in undiluted biofluids. This developed TB biosensor showed a high analytical performance with a wide linear range (1.00 × 10-16 M to 1.00 × 10-11 M) and a low detection limit, indicating that it may open new avenues for direct biosensing of disease markers for clinical samples.


Assuntos
Incrustação Biológica , Técnicas Biossensoriais , Tuberculose , Incrustação Biológica/prevenção & controle , Técnicas Eletroquímicas , Humanos , Peptídeos , Reprodutibilidade dos Testes , Tuberculose/diagnóstico
11.
Soc Sci Med ; 274: 113748, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33648821

RESUMO

Understanding the health-related quality of life (HrQoL) of hospitalized COVID-19 survivors is an emerging global challenge arising from the current pandemic. A qualitative study of the experiences of sixteen hospitalized COVID-19 survivors from Nanning City, China, was conducted using semi-structured telephone interviews in May 2020. These first-hand accounts were critically and empirically analysed to identify emerging health and social issues, and provide potential solutions to improve survivors' quality of life. This in-depth, qualitative study of HrQoL for hospitalized COVID-19 survivors provides the first empirical evidence and conceptual framework with eight dimensions (physical symptoms, anxiety, trauma, economic loss, place-based identity, self-stigma, health self-interventions, and changing lifestyle) for understanding the physiological, psychological, socio-economic and health behavioral aspects of their daily lives. We argue that local and global governments should provide integrated healthcare, social and digital infrastructure to support this vulnerable group. More comparative and multi-disciplinary studies in this area are needed to generate academic standards of assessing health-related quality of life and produce good practice guidelines for promoting urban resilience in response to public health disasters.


Assuntos
COVID-19/terapia , Qualidade de Vida/psicologia , Sobreviventes/psicologia , Adaptação Psicológica , COVID-19/psicologia , China , Humanos , Entrevistas como Assunto , Pesquisa Qualitativa , SARS-CoV-2
12.
Eur J Oper Res ; 291(2): 766-781, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33041472

RESUMO

Portfolio performance evaluation is a major data envelopment analysis (DEA) application in the finance field. Most proposed DEA approaches focus on single-period portfolio performance assessment based on aggregated historical data. However, such an evaluation setting may result in the loss of valuable information in past individual time periods, and violate real-world portfolio managers' and investors' decision making, which generally involves multiple time periods. Furthermore, to our knowledge, all proposed DEA approaches treat the financial assets comprising a portfolio as a "black box": thus there is no information about their individual performance. Moreover, ideal portfolio evaluation models should enable the target portfolio to compare with all possible portfolios, i.e., enabling full diversification of portfolios across all financial assets. Hence, this research aims at developing nested dynamic network DEA models, an additive model being nested within a slacks-based measure (SBM) DEA model, that explicitly utilizes the information in each individual time period to fully and simultaneously measure the multi-period efficiency of a portfolio and its comprised financial assets. The proposed nested dynamic network DEA models, referred to as NDN DEA models, are linear programs with conditional value-at-risk (CVaR) constraints, and infinitely many decision making units (DMUs). In conducting the empirical study, this research applies the NDN DEA models to a real-world case study, in which Markov chain Monte Carlo Bayesian algorithms are used to obtain future performance forecasts in today's highly volatile investment environments.

13.
BMC Infect Dis ; 17(1): 97, 2017 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-28122513

RESUMO

BACKGROUND: To understand the relationship between the Staphylococcus aureus infection rate and the reasonable usage of antibiotics, which will help in the effective control of MRSA infection. METHODS: All data were obtained by the application of the nosocomial infection surveillance network. Drug resistance, departmental sources, and isolated sites as well as infection rate variations of S. aureus were analyzed in the 7-year period in key departments. RESULTS: Between 2008 and 2014, 2525 strains of S. aureus isolates, mainly from sputum, skin/soft tissue, bloodstreams were collected from several hospital departments including respiratory, burn, brain surgery, orthopedics, ICU, and emergency. During these periods, the resistance rate of S. aureus to most drugs, including oxacillin, tetracycline, erythromycin, clindamycin, gentamicin, and ciprofloxacin, showed a tendency to decrease. The resistance to sulphamethoxazole/trimethoprim showed the opposite trend (P = 0.075) and there were no S. aureus strains resistant to linezolid and vancomycin. The MRSA infection rate was different across crucial hospital departments, with the burns department and ICU maintaining a high infection level. Over the 7-year period, both the brain surgery and the emergency departments had an expected upward trend (P < 0.05), while the orthopedic department showed a clear downward trend (P < 0.05) in MRSA infection rate. CONCLUSION: Hospitals should continue to maintain the current pattern of antibiotic administration, while more effective measures should be taken to reduce the high MRSA infection rate in some important hospital departments.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/fisiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação , Antibacterianos/farmacologia , China/epidemiologia , Clindamicina/farmacologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Eritromicina/farmacologia , Hospitais de Ensino , Humanos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia , Centros de Atenção Terciária , Tetraciclina/farmacologia
14.
Appl Opt ; 51(24): 5845-9, 2012 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-22907012

RESUMO

Based on fiber Bragg grating (FBG), an online monitoring system for the etching process of optical fiber in a hydrofluoric (HF) acid solution has been designed. The variation curves of the wavelength shifts of FBGs with etching time at three different temperatures have been obtained and analyzed theoretically. The results show that the etching process of optical fiber in HF acid solution can be understood by the variation of the wavelength shift of FBG with etching time. Finally, required tapered fiber tips can be made by controlling the etching velocity and the pulling velocity of optical fiber from the etching solution.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Fibras Ópticas , Algoritmos , Desenho de Equipamento , Tecnologia de Fibra Óptica/métodos , Ácido Fluorídrico/química , Modelos Teóricos , Refratometria/instrumentação , Refratometria/métodos , Temperatura , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...