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1.
Opt Express ; 32(2): 2418-2431, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297772

RESUMO

Instantaneous phase shifting interferometry technology, the core component of which is the pixel micropolarizer camera, has been widely used in commercial interferometers. This technology has the superiority of single-frame acquisition, vibration insensitivity, and no need for phase shifting devices. However, due to manufacturing defects and accuracy limitations, the extinction ratios (ER) of the micropolarizer array are different and fairly small, directly affecting the phase calculation accuracy. This paper initially derives a theoretical expression for the phase calculation error introduced by the extinction ratio (ER) and proposes the error correction model to reduce phase calculation errors caused by the extinction ratio. The theoretical analysis can serve as an important basis for accurately assessing the polarization characteristics of a pixel micropolarizer camera. Quantifying the impact of the extinction ratios provides significant support for the selection of polarization equipment. In addition, the paper proposes a calibration model to improve measurement accuracy, which can serve as an effective means to reduce the impact of the extinction ratio (ER). The innovative research content revealed the influence of extinction ratio (ER), serving as a valuable complement to the existing analysis and research on extinction ratio (ER).

2.
Appl Opt ; 63(3): 585-594, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294368

RESUMO

For the high-precision fabrication of a continuous phase plate (CPP), a combined decoupling algorithm of single-step decoupling based on the Clairaut-Schwarz theorem and global decoupling by stagewise iteration is proposed. It attempts to address the problem of the low accuracy and limitation of the existing slope-based figuring (SF) model in two-dimensional applications caused by the vector removal coupling between the tool slope influence function and the material removal slope due to the inherent convolution effect in the SF model. The shortcomings of CPP interferometry and the application bottleneck of the Hartmann test in traditional height-based figuring model are studied. The generation mechanism of vector removal coupling is analyzed and compensated. A CPP of 85m m×85m m was successfully machined by the decoupled slope-based figuring model, and the root mean square (RMS) of the surface height error accounted for 6.01% of the RMS of the design value. The research results can effectively improve the convergence and certainty of CPP fabrication using the slope-based figuring model.

3.
Int J Pharm ; 513(1-2): 118-129, 2016 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-27596115

RESUMO

Self-assembled polymeric micelles have been widely applied in anticancer drug delivery systems. Teniposide is a broad spectrum and effective anticancer drug, but its poor water-solubility and adverse effects of commercial formulation (VM-26) restrict its clinical application. In this work, teniposide-loaded polymeric micelles were prepared based on monomethoxy-poly(ethylene glycol)-poly(ε-caprolactone-co-d,l- lactide) (MPEG-PCLA) copolymers through a thin-film hydration method to improve the hydrophilic and reduce the systemic toxicity. The prepared teniposide micelles were without any surfactants or additives and monodisperse with a mean particle size of 29.6±0.3nm. The drug loading and encapsulation efficiency were 18.53±0.41% and 92.63±2.05%, respectively. The encapsulation of teniposide in MPEG-PCLA micelles showed a slow and sustained release behavior of teniposide in vitro and improved the terminal half-life (t1/2), the area under the plasma concentration-time curve (AUC) and retention time of teniposide in vivo compared with VM-26. In addition, teniposide micelles also enhanced the cellular uptake by MCF-7 breast cancer cells in vitro and increased the distribution in tumors in vivo. Teniposide micelles showed an excellent safety with a maximum tolerated dose (MTD) of approximately 50mg teniposide/kg body weight, which was 2.5-fold higher than that of VM-26 (about 20mg teniposide/kg body weight). Furthermore, the intravenous application of teniposide micelles effectively suppressed the growth of subcutaneous MCF-7 tumor in vivo and exhibited a stronger anticancer effect than that of VM-26. These results suggested that we have successfully prepared teniposide-loaded MPEG-PCLA micelles with improved safety, hydrophilic and therapeutic efficiency, which are efficient for teniposide delivery. The prepared teniposide micelles may be promising in breast cancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Portadores de Fármacos/química , Teniposídeo/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Área Sob a Curva , Neoplasias da Mama/patologia , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Feminino , Meia-Vida , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Dose Máxima Tolerável , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Tamanho da Partícula , Poliésteres/química , Polietilenoglicóis/química , Ratos , Ratos Sprague-Dawley , Solubilidade , Teniposídeo/farmacocinética , Teniposídeo/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Artigo em Inglês | MEDLINE | ID: mdl-25965875

RESUMO

An ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to determine acetaminophen (AAP) and dihydrocodeine (DHC) in human plasma simultaneously. Plasma samples were prepared using protein precipitation with acetonitrile, the two analytes and the internal standard midazolam were separated on an Acquity UPLC BEH C18 column and mass spectrometric analysis was performed using a QTrap5500 mass spectrometer coupled with an electro-spray ionization (ESI) source in the positive ion mode. The MRM transitions of m/z 151.2→110.0 and m/z 302.3→199.2 were used to quantify for AAP and DHC, respectively. The linearity of this method was found to be within the concentration range of 50-10000ng/mL for AAP, and 1-100ng/mL for DHC in human plasma, respectively. The lower limit of quantification (LLOQ) was 50ng/mL and 1ng/mL for AAP and DHC in human plasma, respectively. The relative standard deviations (RSD) of intra and inter precision were less than 10% for both AAP and DHC. The analysis time of per sample was 1.0min. The developed and validated method was successfully applied to a pharmacokinetic study of AAP (500mg) with DHC (20mg) capsule in Chinese healthy volunteers (N=20).


Assuntos
Acetaminofen/sangue , Cromatografia Líquida de Alta Pressão/métodos , Codeína/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Acetaminofen/química , Acetaminofen/farmacocinética , Codeína/sangue , Codeína/química , Codeína/farmacocinética , Estabilidade de Medicamentos , Humanos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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