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How rotational speed of planetary ball mill and polymer load influence the performance and water vapor sorption in solid dispersions composed of tadalafil and soluplus

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Particuology 2023年第2期73卷 37-46页

作者： Karol Kubat Anna Krupa Witold Brniak Agnieszka Węgrzyn Dorota Majda Agata Bogdał Hubert Harańczyk Department of Medical Physics Faculty of PhysicsInstitute of PhysicsJagiellonian UniversityCracowPoland department of Pharmaceutical Technology and Biopharmaceutics Faculty of PharmacyCollegium MedicumJagiellonian UniversityCracowPoland Faculty of Chemistry Jagiellonian UniversityCracowPoland

The presence of residual water may deteriorate the performance of amorphous solid dispersions prepared by ball milling,affecting molecular mobility,crystallinity,particle size and finally,the drug dissolution rate.As the stability of these metastable systems depend on both formulation and process variables,the aim of this study was to assess for the first time,the impact that the polymer load and the rotational speed applied upon high energy ball milling could have on the performance of binary co-milled solid dispersions composed of tadalafil(a hydrophobic crystalline drug)and Soluplus(an amphiphilic,hygroscopic amorphous polymer).Each of these variables was tested at three levels.Scanning electron microscopy,laser diffraction and X-ray powder diffraction were used to analyze morphology,particle size distribution and crystallinity of ball milled formulations respectively.Dissolution studies were also carried out.Advanced tools of applied physics,namely solid state 1H NMR and relaxometry were used to assess the structure and water mobility upon gaseous phase hydration on storage.It was shown that both tested variables determined the particle size of the formulation.When the rotational speed of 400 rpm was used,all solid dispersion were XRD-amorphous,but to ensure the immediate release of tadalafil its micellar solubilization in Soluplus was necessary.While the formulation was exposed to water vapor,the hydration level increased with an increasing polymer load as well.Hence,the rotational speed governed the space available for the adsorption of water molecules and their organization in a monolayer or multilayers.Such behavior may have impact on the kinetics of the amorphous drug recrystallization,and finally deteriorate its dissolution.

关键词： Tadalafil Soluplus Solid dispersion Relaxation time Milling NMR

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Effects of time delays in a mathematical bone model

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Chinese physics B 2017年第3期26卷 251-257页

作者：王莉芳仇康贾亚 Institute of Biophysics and department of physics Central China Normal University department of Mathematics and physics Xuzhou Medical University

In this paper we propose a mathematical model of bone remodeling with time delays of both osteoclast-derived paracrine signaling of tumor and tumor-derived paracrine signaling of osteoclast. The effects of time delays on the growth of tumor cells and bone system are studied in multiple myeloma-induced bone disease. In the case of small osteoclast-derived paracrine signaling, it is found that the growth of tumor cells slows down, the oscillation period of the ratio of osteoclasts to osteoblasts is extended with increasing time delay, and there is a competition between the delay and osteoclast-derived paracrine signaling. In the ease of large tumor-derived paraerine signaling, the tumor-derived paracrine signaling can induce a more significant decline in tumor growth for long time delay, and thus slowing down the progression of bone disease. There is an optimal coupling between the tumor-derived paracrine signaling of osteoclasts and time delay during the progressions of bone diseases, which suppresses the tumor growth and the regression of bone disease.

关键词： time delays oscillation model of bone remodeling

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Properties of surface waves in granular media under gravity

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Chinese physics B 2014年第5期23卷 355-359页

作者：郑鹤鹏 department of Mathematics and physics Guilin medical University

Acoustical waves propagating along the free surface of granular media under gravity are investigated in the framework of elasticity theory. The influence of stress on a surface wave is analyzed. The results have shown that two types of surface waves, namely sagittal and transverse modes exist depending on initial stress states, which may have some influence on the dispersion relations of surface waves, but the influence is not great. Considering that the present experimental accuracy is far from distinguishing this detail, the validity of elasticity theory on the surface waves propagating in granular media can still be maintained.

关键词： granular matter stress surface waves

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Tunneling Negative Magnetoresistance via δ Doping in a Graphene-Based Magnetic Tunnel Junction

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Chinese physics Letters 2016年第3期33卷 95-98页

作者：袁建辉陈妮莫华张燕张志海 department of physics Guangxi Medical University School of physics and Electronics Yancheng Teachers University

We investigate the tunneling magnetoresistance via δ doping in a graphei2e-based magnetic tunnel junction in detail. It is found that the transmission probability and the conductance oscillates with the position and the aptitude of the 8 doping. Also, both the transmission probability and the conductance at the paxallel configuration are suppressed by the magnetic field more obviously than that at the antiparallel configuration, which implies a large negative magnetoresistance for this device. The results show that the negative magnetoresistance of over 300% at B = 1.0 T is observed by choosing suitable doped parameters, and the temperature plays an important role in the magnetoresistance. Thus it is possible to open a way to effectively manipulate the magnetoresistance devices, and to make a type of magnetoresistance device by controlling the structural parameter of the δ doping.

关键词： of it in Tunneling Negative Magnetoresistance via is that for

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Preparation and Osteogenic Efficacy of Emodin-loaded Hydroxyapatite Electrospun Fibers

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Journal of Bionic Engineering 2023年第3期20卷 1060-1071页

作者： Yiwen Pan Mu He Shaoqing Chen Yanyan Meng Cheli Wang Xinye Ni School of Pharmacy Changzhou UniversityChangzhou213000China department of Radiotherapy Changzhou Second People’s HospitalNanjing Medical UniversityChangzhou213000China Laboratory of medical physics Center Nanjing Medical UniversityNanjing210000China Changzhou Key Laboratory of medical physics Changzhou213000China

Biological scaffolds have been the focus of bone tissue engineering research in recent years. In this paper, emodin (EM), macromolecular compound polycaprolactone (PCL), and hydroxyapatite (HA) were used as raw materials to prepare EM/PCL/HA fibers containing different EM ratios by electrospinning, and the properties and osteogenic efficacy of EM/PCL/HA were studied. Scanning electron microscopy, transmission electron microscopy, and atomic force microscopy were used to characterize the structures of HA and the electrospun fibers. Results showed that HA has high crystallinity and loose porous structure, and the electrospun fibers have a smooth and flat surface. In vitro release results showed that EM was slowly released from EM/PCL/HA within 216 h. Cell proliferation assay in mouse embryonic osteoblast precursor cells (MC3T3-E1) exhibited that 5% EM/PCL/HA had the best effect on promoting cell proliferation. Alkaline phosphatase (ALP) and mineralized nodules staining results also showed that 5% EM/PCL/HA had the best effect on promoting osteogenic differentiation. qRT-PCR results showed that the mRNA expression level of osteoblast differentiation markers, namely, bone morphogenetic protein (BMP)-2, BMP-9, and osteocalcin were significantly upregulated by 5% EM/PCL/HA treatment. These results indicate that EM/PCL/HA is a potential osteogenic material, which can provide a reference for the development of bone injury repair materials.

关键词： Emodin Hydroxyapatite Electrospinning Bone regeneration

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Effects of the two-color laser on relativistic muon motion

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Nuclear Science and Techniques 2014年第2期25卷 17-25页

作者：石春花苏晋周晋阳 department of Biomedical Engineering Changzhi Medical College department of physics Changzhi Medical College

Considering the mixture after muon-catalyzed fusion(μCF) reaction as overdense plasma,we analyze muon motion in the plasma induced by a linearly polarized two-colour laser,particularly,the effect of laser parameters on the muon momentum and trajectory.The results show that muon drift along the propagation of laser and oscillation perpendicular to the propagation remain after the end of the laser pulse.Under appropriate parameters,muon can go from the skin layer into field-free matter in a time period of much less than the pulse duration.The electric-field strength ratio or frequency ratio of the fundamental to the harmonic has more influence on muon oscillation.The laser affects little on other particles in the plasma.Hence,in theory,this work can avoid muon sticking to α effectively and reduce muon-loss probability in μCF.

关键词：双色激光运动效果 μ介子相对论稠密等离子体脉冲持续时间线偏振光激光参数

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Use of ebselen as a neuroprotective agent in rat spinal cord subjected to traumatic injury

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Neural Regeneration Research 2019年第7期14卷 1255-1261页

作者： Wojciech ?lusarczyk Edyta Olakowska Magdalena Larysz-Brysz Izabella Woszczycka-Korczyńska Daria Gendosz de Carrillo W?adys?aw P.W?glarz Joanna Lewin-Kowalik Wies?aw Marcol department of Physiology Medical University of Silesia Institute of Nuclear physics Polish Academy of Sciences

Spinal cord injury(SCI) causes disturbances of motor skills.Free radicals have been shown to be essential for the development of spinal cord trauma.Despite some progress,until now no effective pharmacological therapies against SCI have been verified.The purpose of our experiment was to investigate the neuroprotective effects of ebselen on experimental SCI.Twenty-two rats subjected to SCI were randomly subjected to SCI with no further treatment(n = 10) or intragastric administration of ebselen(10 mg/kg) immediately and 24 hours after SCI.Behavioral changes were assessed using the Basso,Beattie,and Bresnahan locomotor scale and footprint test during 12 weeks after SCI.Histopathological and immunohistochemical analyses of spinal cords and brains were performed at 12 weeks after SCI.Magnetic resonance imaging analysis of spinal cords was also performed at 12 weeks after SCI.Rats treated with ebselen presented only limited neurobehavioral progress as well as reduced spinal cord injuries compared with the control group,namely length of lesions(cysts/scars)visualized histopathologically in the spinal cord sections was less but cavity area was very similar.The same pattern was found in T2-weighted magnetic resonance images(cavities) and diffusion-weighted images(scars).The number of FluoroGold retrogradely labeled neurons in brain stem and motor cortex was several-fold higher in ebselen-treated rats than in the control group.The findings suggest that ebselen has only limited neuroprotective effects on injured spinal cord.All exprimental procedures were approved by the Local Animal Ethics Committee for Experiments on Animals in Katowice(Katowice,Poland)(approval No.19/2009).

关键词： ebselen antioxidant neuroprotection neuroregeneration spinal cord injury spinal cord repair functional recovery

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Near-infrared-II deep tissue fluorescence microscopy and application

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Nano Research 2023年第1期16卷 692-714页

作者： Pengfei Liu Rong Zhao Hongwei Li Tianyu Zhu Yuan Li Hao Wang Xiao-Dong Zhang Academy of medical Engineering and Translational Medicine Medical CollegeTianjin UniversityTianjin 300072China department of physics and Tianjin Key Laboratory of Low Dimensional Materials physics and Preparing Technology School of SciencesTianjin UniversityTianjin 300350China

Fluorescence imaging has become an essential tool in biomedical research.However,non-invasive deep-tissue threedimensional optical in vivo imaging with the high spatiotemporal resolution is challenging due to the interaction between photons and tissues.Beam shaping has been used to tailor microscopy techniques to enhance microscope performance.The nearinfrared window(NIR)between 700 and 1,700 nm,generally emphasized as the NIR-II(1,000–1,700 nm)window,has been developed into a promising bio-optical solution chosen as the lower interaction effect in this spectrum,showing potential in basic biological research and clinical application.In this review,we summarize the existing methods to increase penetration depth and extensively describe biological microscopy techniques,NIR-II spectral windows,and fluorophores.Strategies to improve bioimaging performance and NIR-II imaging applications are introduced.Based on the current research achievements,we elucidate the main challenges and provide some recommendations and prospects for deep tissue penetration fluorescence for future biomedical applications.

关键词： deep tissue penetration microscopy near-infrared II imaging fluorophore

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Optimized thyroid transcription factor-1 core promoter-driven microRNA-7 expression effectively inhibits the growth of human non-small-cell lung cancer cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2022年第11期23卷 915-930页

作者： Shipeng CHEN Lian GUAN Xu ZHAO Jing YANG Longqing CHEN Mengmeng GUO Juanjuan ZHAO Chao CHEN Ya ZHOU Yong HAN Lin XU Special Key Laboratory of Gene Detection and Therapy&Base for Talents in Biotherapy of Guizhou Province Zunyi 563000China department of Immunology Zunyi Medical UniversityZunyi 563000China Department of Medical Physics Zunyi Medical UniversityZunyi 563000China department of Physiology Zunyi Medical UniversityZunyi 563000China

Targeted gene therapy has become a promising approach for lung cancer treatment.In our previous work,we reported that the targeted expression of microRNA-7(miR-7)operated by thyroid transcription factor-1(TTF-1)promoter inhibited the growth of human lung cancer cells in vitro and in vivo;however,the intervention efficiency needed to be further improved.In this study,we identified the core promoter of TTF-1(from-1299 bp to-871 bp)by 5’deletion assay and screened out the putative transcription factors nuclear factor-1(NF-1)and activator protein-1(AP-1).Further analysis revealed that the expression level of NF-1,but not AP-1,was positively connected with the activation of TTF-1 core promoter in human non-small-cell lung cancer(NSCLC)cells.Moreover,the silencing of NF-1 could reduce the expression level of miR-7 operated by TTF-1 core promoter.Of note,we optimized four distinct sequences to form additional NF-1-binding sites(TGGCA)in the sequence of TTF-1 core promoter(termed asTTF-1 promoter),and verified the binding efficiency of NF-1 on theTTF-1 promoter by electrophoretic mobility shift assay(EMSA).As expected,theTTF-1 promoter could more effectively drive miR-7 expression and inhibit the growth of human NSCLC cells in vitro,accompanied by a reduced transduction of NADH dehydrogenase(ubiquinone)1αsubcomplex 4(NDUFA4)/protein kinase B(Akt)pathway.Consistently,TTF-1 promoter-driven miR-7expression could also effectively abrogate the growth and metastasis of tumor cells in a murine xenograft model of human NSCLC.Finally,no significant changes were detected in the biological indicators or the histology of some important tissues and organs,including heart,liver,and spleen.On the whole,our study revealed that the optimized TTF-1 promoter could more effectively operate miR-7 to influence the growth of human NSCLC cells,providing a new basis for the development of microRNA-based targeting gene therapy against clinical lung cancer.

关键词： Lung cancer Thyroid transcription factor-1(TTF-1) Promoter MicroRNA-7(miR-7) Nuclear factor-1(NF-1)

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Evaluations of dielectric property and drug release profile of 5-FU patches based on plasma charged electrets

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Plasma Science and Technology 2018年第5期20卷 110-116页

作者：苑旺梁合鹃黄平安晓强江键崔黎丽 department of physics and Mathematics College of Basic Medical SciencesSecond Military Medical University department of Inorganic Chemistry School of PharmacySecond Military Medical University

In the present study,the electret 5-fluorouracil patch was developed,the effective surface potential,piezoelectric coefficient d33,open-circuit thermally stimulated discharge（TSD） current spectra and shear adhesion of the patch were measured.The drug release profile of the patch was determined by using high performance liquid chromatography method.A stable potential difference which was positively dependent on the surface potential of the electret was generated on two sides of the patch.The measurements of d33 coefficient,TSD current spectra and adhesion performance showed that the electrostatic field of the electret could cause polarization and cohesive strength decreasing of the matrix molecules,change the distribution and interaction of the drug molecules in patch,therefore to increase the release of drug from the transdermal patch.

关键词： electret hypertrophic scar thermally stimulated discharge current 5-fluorouracil,patch piezoelectric coefficient

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