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1.
J Synchrotron Radiat ; 31(Pt 1): 177-185, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37971956

RESUMEN

The Shanghai Soft X-ray Free-Electron Laser (SXFEL) is the first X-ray free-electron laser facility in China. The SASE beamline, which consists of a pink-beam branch and a mono-beam branch, is one of the two beamlines in the Phase-I construction. The pink-beam branch opened for users in 2023 after successful first-round beamline commissioning. In this paper, the design of the beamline is presented and the performance of the pink-beam branch is reported. The measured energy-resolving power of the online spectrometer is over 6000 @ 400 eV. The focusing spot size of the pink beam is less than 3 µm in both the horizontal and vertical at the endstation.

2.
J Synchrotron Radiat ; 30(Pt 3): 505-513, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36947163

RESUMEN

The characterization of X-ray focal spots is of great significance for the diagnosis and performance optimization of focusing systems. X-ray free-electron lasers (XFELs) are the latest generation of X-ray sources with ultrahigh brilliance, ultrashort pulse duration and nearly full transverse coherence. Because each XFEL pulse is unique and has an ultrahigh peak intensity, it is difficult to characterize its focal spot size individually with full power. Herein, a method for characterizing the spot size at the focus position is proposed based on coherent diffraction imaging. A numerical simulation was conducted to verify the feasibility of the proposed method. The focal spot size of the Coherent Scattering and Imaging endstation at the Shanghai Soft X-ray Free Electron Laser Facility was characterized using the method. The full width at half-maxima of the focal spot intensity and spot size in the horizontal and vertical directions were calculated to be 2.10 ± 0.24 µm and 2.00 ± 0.20 µm, respectively. An ablation imprint on the silicon frame was used to validate the results of the proposed method.

3.
Anal Chem ; 94(38): 13136-13144, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36111576

RESUMEN

Characterizing interactions between microbial cells and their specific inhibitory drugs is essential for developing effective drugs and understanding the therapeutic mechanism. Functional metal nanoclusters can be effective inhibitory agents against microorganisms according to various characterization methods, but quantitative three-dimensional (3D) spatial structural analysis of intact cells is lacking. Herein, using coherent X-ray diffraction imaging, we performed in situ 3D visualization of unstained Staphylococcus aureus cells treated with peptide-mineralized Au-cluster probes at a resolution of ∼47 nm. Subsequent 3D mass-density mapping and quantitative structural analyses of S. aureus in different degrees of destruction showed that the bacterial cell wall was damaged and cytoplasmic constituents were released from cells, confirming the significant antibacterial effects of the Au-cluster probe. This study provides a promising nondestructive approach for quantitative imaging and paves the way for further research into microbe-inhibitor drug interactions.


Asunto(s)
Imagenología Tridimensional , Staphylococcus aureus , Antibacterianos/química , Antibacterianos/farmacología , Imagenología Tridimensional/métodos , Pruebas de Sensibilidad Microbiana , Péptidos/farmacología , Difracción de Rayos X
4.
Opt Express ; 26(23): 30128-30145, 2018 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-30469892

RESUMEN

In common ptychographic coherent diffractive imaging (PCDI) systems, the probe-generating devices typically exhibit strong scattering, which is not fully used. Here, we report the reasonableness of using the diffraction pattern of the probe-generating device as the frequency-domain information of the scanning probe located in the sample plane, and we propose a method introducing this frequency-domain information into an iterative process to improve the imaging quality of PCDI. The new method was demonstrated using both a visible laser source and a synchrotron radiation X-ray source; the proposed method significantly improved the imaging quality in both demonstrations.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3315-8, 2015 Dec.
Artículo en Zh | MEDLINE | ID: mdl-26964201

RESUMEN

A new method of terahertz (THz) imaging based on the mean absorption is proposed. Terahertz radiation is an electromagnetic radiation in the range between millimeter waves and far infrared. THz pulse imaging emerges as a novel tool in many fields because of its low energy and non-ionizing character, such as material, chemical, biological medicine and food safety. A character of THz imaging technique is it can get large amount of information. How to extract the useful parameter from the large amount of information and reconstruct sample's image is a key technology in THz imaging. Some efforts have been done for advanced visualization methods to extract the information of interest from the raw data. Both time domain and frequency domain visualization methods can be applied to extract information on the physical properties of samples from THz imaging raw data. The process of extracting useful parameter from raw data of the new method based on the mean absorption was given in this article. This method relates to the sample absorption and thickness, it delivers good signal to noise ratio in the images, and the dispersion effects are cancelled. A paper with a "THz" shape hole was taken as the sample to do the experiment. Traditional THz amplitude imaging methods in time domain and frequency domain are used to achieve the sample's image, such as relative reduction of pulse maximum imaging method, relative power loss imaging method, and relative power loss at specific frequency imaging method. The sample's information that reflected by these methods and the characteristics of these methods are discussed. The method base on the mean absorption within a certain frequency is also used to reconstruct sample's image. The experimental results show that this new method can well reflect the true information of the sample. And it can achieve a clearer image than the other traditional THz amplitude imaging methods. All the experimental results and theoretical analyses indicate that the method base on the mean absorption within a certain frequency can reflects sample absorb and thickness information, it can achieve good signal to noise ratio in the images. Because the absorption is mean absorption within in a certain frequency, so the method proposed in this article is especially suitable for samples with simple structure. And this new method can be a useful added tool for the other traditional THz amplitude imaging methods.

6.
Zhongguo Fei Ai Za Zhi ; 27(4): 306-320, 2024 Apr 20.
Artículo en Zh | MEDLINE | ID: mdl-38769834

RESUMEN

The advent of immune checkpoint inhibitors (ICIs) has greatly improved the prognosis of advanced lung cancer patients, but can lead to pseudoprogression (PsP), which complicates clinical evaluation and management. PsP is manifested as temporary enlargement of the tumour or the appearance of new lesions, etc., and improvement in imaging occurs with continued treatment, mostly without worsening of clinical symptoms. Currently, there are still difficulties in the early diagnosis of PsP, and its occurrence mechanism is not yet clear, lacking good predictive factors and related biomarkers. This article reviews the current research status of PsP of ICIs in non-small cell lung cancer in order to provide helpful clinical strategies for oncologists using these drugs.
.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Inhibidores de Puntos de Control Inmunológico , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/patología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/inmunología , Progresión de la Enfermedad
7.
J Trace Elem Med Biol ; 84: 127437, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38564977

RESUMEN

INTRODUCTION: Bimetallic nanoparticles, specifically Zinc oxide (ZnO) and Silver (Ag), continue to much outperform other nanoparticles investigated for a variety of biological uses in the field of cancer therapy. This study introduces biosynthesis of bimetallic silver/zinc oxide nanocomposites (Ag@ZnO NCs) using the Crocus sativus extract and evaluates their anti-cancer properties against cervical cancer. METHODS: The process of generating bimetallic nanoparticles (NPs), namely Ag@ZnO NCs, through the utilization of Crocus sativus extract proved to be uncomplicated and eco-friendly. Various methods, such as UV-vis, DLS, FTIR, EDX, and SEM analyses, were utilized to characterize the generated Ag@ZnO NCs. The MTT assay was employed to assess the cytotoxic properties of biosynthesized bimetallic Ag@ZnO NCs against the HeLa cervical cancer cell line. Moreover, the impact of Ag@ZnO NCs on HeLa cells was assessed by examining cell survival, ROS production, MMP levels, and induced apoptosis. Through western blot analysis, the expression levels of the PI3K, AKT, mTOR, Cyclin D, and CDK proteins seemed to be ascertained. Using flow cytometry, the cancer cells' progression through necrosis and apoptosis, in addition to the cell cycle analysis, were investigated. RESULTS: Bimetallic Ag@ZnO NCs that were biosynthesized showed a high degree of stability, as demonstrated by the physicochemical assessments. The median size of the particles in these NCs was approximately 80-90 nm, and their zeta potential was -14.70 mV. AgNPs and ZnO were found, according to EDX data. Further, Ag@ZnO NCs hold promise as a potential treatment for cervical cancer. After 24 hours of treatment, a dosage of 5 µg/mL or higher resulted in a maximum inhibitory effect of 58 ± 2.9. The concurrent application of Ag/ZnO NPs to HeLa cells resulted in elevated apoptotic signals and a significant generation of reactive oxygen species (ROS). As a result, the bimettalic Ag@ZnO NCs treatment has been recognized as a chemotherapeutic intervention by inhibiting the production of PI3K, AKT, and mTOR-mediated regulation of propagation and cell cycle-regulating proteins. CONCLUSIONS: The research yielded important insights into the cytotoxic etiology of biosynthesized bimetallic Ag@ZnO NCs against HeLa cells. The biosynthesized bimetallic Ag@ZnO NCs have a significant antitumor potential, which appears to be associated with the development of oxidative stress, which inhibits the development of the cell cycle and the proliferation of cells. Therefore, in the future, biosynthesized bimetallic Ag@ZnO NCs may be used as a powerful anticancer drug to treat cervical cancer.


Asunto(s)
Antineoplásicos , Apoptosis , Proliferación Celular , Nanocompuestos , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Plata , Serina-Treonina Quinasas TOR , Neoplasias del Cuello Uterino , Óxido de Zinc , Humanos , Óxido de Zinc/química , Óxido de Zinc/farmacología , Plata/química , Plata/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Femenino , Células HeLa , Fosfatidilinositol 3-Quinasas/metabolismo , Nanocompuestos/química , Antineoplásicos/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Nanopartículas del Metal/química , Ensayos de Selección de Medicamentos Antitumorales , Transducción de Señal/efectos de los fármacos
8.
Dermatology ; 225(1): 75-80, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22907159

RESUMEN

BACKGROUND: Since the three-dimensional (3-D) structure of dermal tissue has an important role in regulating cell behavior and directing the wound healing process, the characteristic of the 3-D structure of dermal tissue needs to be clarified. OBJECTIVE: To explore the different 3-D structures between normal and scar dermal tissues. MATERIAL AND METHODS: Phase-contrast microtomography with synchrotron radiation technology was applied to detect the 3-D structure of dermal tissues. RESULTS: The normal dermal tissue consists of elliptical structures formed by fiber bundles interwoven in a helical manner. A regular louver-like structure was observed on the fibers. In scar tissue, the fiber bundles were arrayed in parallel, the louver-like structures were disordered. CONCLUSION: The study demonstrates the mesoscopic difference between normal dermal tissue and scar tissue, suggests that the high level of interweaving capability of collagen is compromised/lost when dermal tissue is injured, and provides a basis for future studies.


Asunto(s)
Cicatriz/diagnóstico por imagen , Colágeno/ultraestructura , Dermis/diagnóstico por imagen , Sincrotrones , Cicatrización de Heridas/fisiología , Microtomografía por Rayos X/métodos , Dermis/lesiones , Humanos , Imagenología Tridimensional/métodos
9.
IUCrJ ; 9(Pt 2): 223-230, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35371506

RESUMEN

Radiation damage and a low signal-to-noise ratio are the primary factors that limit spatial resolution in coherent diffraction imaging (CDI) of biomaterials using X-ray sources. Introduced here is a clustering algorithm named ConvRe based on deep learning, and it is applied to obtain accurate and consistent image reconstruction from noisy diffraction patterns of weakly scattering biomaterials. To investigate the impact of X-ray radiation on soft biomaterials, CDI experiments were performed on mitochondria from human embryonic kidney cells using synchrotron radiation. Benefiting from the new algorithm, structural changes in the mitochondria induced by X-ray radiation damage were quantitatively characterized and analysed at the nanoscale with different radiation doses. This work also provides a promising approach for improving the imaging quality of biomaterials with XFEL-based plane-wave CDI.

10.
Chin J Integr Med ; 22(2): 124-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26272548

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of Pai-Neng-Da Capsule (panaxadiol saponins component, PND), a new Chinese patent medicine, on patients with chronic aplastic anemia (CAA) and to explore the optimal therapeutic regimen for CAA. METHOD: A total of 36 patients with CAA were enrolled and divided into three groups: the AP group (20 cases, andriol 120 mg/day + PND 240 mg/day), the ACP group (13 cases, andriol 120 mg/day + cyclosporine 3-6 mg kd(-1) day(-1) + PND 240 mg/day), and the PND group (3 cases, PND 240 mg/day). All patients were treated and followed up for 6 months. Peripheral blood counts, renal and hepatic function and Chinese medical (CM) symptoms of patients were assessed and all indices were gathered at the beginning and end of the study. RESULT: In the AP group, no significant hematologic difference was observed at the end of 6-month treatment comparing with the beginning. In the ACP group, the blood counts were maintained at the same level after the 6-month treatment. In the PND group, trilineage hematologic improvement was displayed at the end of 6-month treatment comparing with the beginning. No significant difference was showed in renal and hepatic function in all patients. All patients' clinical symptom improved according to CM symptom score. The effective rates were 95%, 73% and 100%, respectively. CONCLUSION: PND improved the efficacy and decreased side effects by cutting down the dosage of andriol, and it could also improve patients' clinical symptom and quality of life. PND were effective and safe in the treatment of CAA, it could be used alone or in combination with pharmacological agents such as andriol and cyclosporine.


Asunto(s)
Anemia Aplásica/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Saponinas/uso terapéutico , Adolescente , Adulto , Anciano , Anemia Aplásica/sangre , Cápsulas , Enfermedad Crónica , Medicamentos Herbarios Chinos/efectos adversos , Recuento de Eritrocitos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Saponinas/efectos adversos , Resultado del Tratamiento , Adulto Joven
11.
Eur J Pharm Sci ; 84: 132-8, 2016 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26802550

RESUMEN

Osmotic pump tablets are reliable oral controlled drug delivery systems based on their semipermeable membrane coating. This research used synchrotron radiation-based Fourier transform infrared (SR-FTIR) microspectroscopy and imaging to investigate the hydration induced material transfer in the membranes of osmotic pump tablets. SR-FTIR was applied to record and map the chemical information of a micro-region of the membranes, composed of cellulose acetate (CA, as the water insoluble matrix) and polyethylene glycol (PEG, as the soluble pore forming agent and plasticizing agent). The microstructure and chemical change of membranes hydrated for 0, 5, 10 and 30min were measured using SR-FTIR, combined with scanning electronic microscopy and atom force microscopy. The SR-FTIR microspectroscopy results indicated that there was a major change at the absorption range of 2700-3100cm(-1) in the membranes after different periods of hydration time. The absorption bands at 2870-2880cm(-1) and 2950-2960cm(-1) were assigned to represent CA and PEG, respectively. The chemical group signal distribution illustrated by the ratio of PEG to CA demonstrated that the trigger of drug release in the preliminary stage was due to the rapid transfer of PEG into liquid medium with a sharp decrease of PEG in the membranes. The SR-FTIR mapping results have demonstrated the hydration induced material transfer in the membranes of osmotic pump tablets and enabled reassessment of the drug release mechanism of membrane controlled osmotic pump systems.


Asunto(s)
Comprimidos/química , Captopril/química , Celulosa/análogos & derivados , Celulosa/química , Preparaciones de Acción Retardada/química , Liberación de Fármacos , Ósmosis , Polietilenglicoles/química , Espectroscopía Infrarroja por Transformada de Fourier , Sincrotrones
12.
Acta Pharm Sin B ; 5(3): 270-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26579456

RESUMEN

The present study establishes a visualization method for the measurement of the distribution and localization of protein/peptide constituents within a single poly-lactide-co-glycolide (PLGA) microsphere using synchrotron radiation-based Fourier-transform infrared spectromicroscopy (SR-FTIR). The representative infrared wavenumbers specific for protein/peptide (Exenatide) and excipient (PLGA) were identified and chemical maps at the single microsphere level were generated by measuring and plotting the intensity of these specific bands. For quantitative analysis of the distribution within microspheres, Matlab software was used to transform the map file into a 3D matrix and the matrix values specific for the drug and excipient were extracted. Comparison of the normalized SR-FTIR maps of PLGA and Exenatide indicated that PLGA was uniformly distributed, while Exenatide was relatively non-uniformly distributed in the microspheres. In conclusion, SR-FTIR is a rapid, nondestructive and sensitive detection technology to provide the distribution of chemical constituents and functional groups in microparticles and microspheres.

13.
J Tissue Eng Regen Med ; 8(10): 794-800, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22865629

RESUMEN

Thorough knowledge of dermal tissue structure in three dimensions is not only a prerequisite for understanding the relationship between cells and their extracellular matrix, but also provides a basis for understanding of wound healing and scar formation for designing the ideal scaffold for skin tissue engineering. Here, we show for the first time the visualization of the three dimensional (3D) structure of dermal tissue by phase-contrast microtomography (µCT) with third-generation synchrotron radiation (SR). Compared with irregular dermal tissue (such as scar tissue), the normal dermal tissues were found to consist of a network of elliptically shaped regions containing a web of fibre bundles. The bundles, composed of fibres, were found to be orientated along specific directions, indicative of helical weaving. A regular array of dentate structure was shown on the fibres. The results showed that phase-contrast µCT with SR had a distinct advantage in accurately viewing the 3D microstructure of dermal tissues.


Asunto(s)
Dermis/diagnóstico por imagen , Dermis/metabolismo , Matriz Extracelular/diagnóstico por imagen , Matriz Extracelular/metabolismo , Animales , Tomografía con Microscopio Electrónico , Masculino , Radiografía , Ratas , Ratas Sprague-Dawley
14.
Zhonghua Shao Shang Za Zhi ; 28(1): 5-8, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22490532

RESUMEN

OBJECTIVE: To compare the morphological difference between dermal tissue of normal skin and that of scar in rat, and to explore its structural pattern. METHODS: The full-thickness skin and the scar tissue formed 3 weeks after wound healing from SD rats were harvested as samples, which were prepared appropriately afterwards. Samples were scanned and imaged with synchrotron radiation technology, micro-CT, and phase-contrast imaging technology. The images were rebuilt with three-dimensional software. RESULTS: The micro-CT was materialized by using X-ray generated by synchrotron radiation light source. The structure of dermal tissues was clearly shown with the assistance of phase-contrast imaging technology in the process. It was demonstrated that the dermal tissues of normal skin of rat were mainly composed of collagenous fibers, which twined together to form an olive-like structure. These olive-like structures as basic units were arranged randomly in a certain way. The collagenous fibers in dermal tissue of the scar were arranged in a parallel manner, while some fibers were crooked and arranged in a disorderly manner. CONCLUSIONS: Dermal tissue of normal skin in rat has stable three-dimensional structure, and its basic structure and manner of composition are obviously different from those of scar dermal tissue.


Asunto(s)
Cicatriz/diagnóstico por imagen , Dermis/diagnóstico por imagen , Imagenología Tridimensional/métodos , Animales , Dermis/patología , Masculino , Microscopía de Contraste de Fase , Ratas , Ratas Sprague-Dawley , Piel/diagnóstico por imagen , Sincrotrones , Tomografía Computarizada por Rayos X , Cicatrización de Heridas
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