Publications by authors named "Xiaoman Duan"

Article Synopsis
  • Propagation-based imaging computed tomography (PBI-CT) is gaining popularity for visualizing low-density materials thanks to its high resolution and image contrast, but it poses radiation risks in live animal imaging due to high doses.
  • This study integrates a deep learning method called Sparse2Noise with PBI-CT to significantly reduce radiation exposure (up to 90%) while preserving image quality, showing improved results over traditional low-dose imaging methods.
  • The findings indicate that Sparse2Noise provides a better signal-to-noise ratio compared to two other advanced low-dose algorithms, enhancing the effectiveness of PBI-CT for biomedical applications.
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Article Synopsis
  • - Hydrogel-based scaffolds are popular in soft tissue regeneration for their ability to create a biocompatible and tissue-like environment, but assessing their mechanical properties and microstructure post-implantation poses challenges due to the destructiveness of traditional testing methods.
  • - The study explores the use of synchrotron radiation propagation-based imaging-computed tomography (SR-PBI-CT) as a non-destructive technique for characterizing the mechanical and internal properties of these scaffolds.
  • - Researchers created hydrogel scaffolds with specific biomaterial inks, tested their compressive strength, and simultaneously imaged them under mechanical load to determine their stress-strain behavior and internal microstructure, achieving Young's modulus values between 5-25 kPa.
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Fluorescent DNA assays are promising in disease diagnosis, environmental monitoring, and drug screening, encompassing both heterogeneous and homogeneous assay types. Nevertheless, heterogeneous assays suffer from tedious washing steps and slow reaction kinetics, whereas homogenous assays require well-designed fluorophore pairs to modulate signal off/on. Herein, we developed a cost-effective and efficient quencher-free fluorescent DNA assay using an aqueous two-phase system (ATPS).

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Assembling DNA on solid surfaces is fundamental to surface-based DNA technology. However, precise control over DNA conformation and organization at solid-liquid interfaces remains a challenge, resulting in limited stability and sensitivity in biosensing applications. We herein communicate a simple and robust method for creating highly uniform DNA monolayers on gold surfaces by a freeze-thawing process.

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Background: Synchrotron radiation computed tomography (SR-CT) holds promise for high-resolution in vivo imaging. Notably, the reconstruction of SR-CT images necessitates a large set of data to be captured with sufficient photons from multiple angles, resulting in high radiation dose received by the object. Reducing the number of projections and/or photon flux is a straightforward means to lessen the radiation dose, however, compromises data completeness, thus introducing noises and artifacts.

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We herein report a convenient and effective method for the purification of DNA-conjugated materials with a benchtop minicentrifuge. We demonstrate the fast isolation of DNA-modified small gold nanoparticles (5 nm), liposomes, and DNA nanostructures using fluorescent methods and gel electrophoresis. Our method is cost-effective and efficient and would accelerate the development of DNA nanotechnology.

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Engineering cardiac tissue that mimics the hierarchical structure of cardiac tissue remains challenging, raising the need for developing novel methods capable of creating structures with high complexity. Three-dimensional (3D)-printing techniques are among promising methods for engineering complex tissue constructs with high precision. By means of 3D printing, this study aims to develop cardiac constructs with a novel angular structure mimicking cardiac architecture from alginate (Alg) and gelatin (Gel) composite.

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Visualization of low-density tissue scaffolds made from hydrogels is important yet challenging in tissue engineering and regenerative medicine (TERM). For this, synchrotron radiation propagation-based imaging computed tomography (SR-PBI-CT) has great potential, but is limited due to the ring artifacts commonly observed in SR-PBI-CT images. To address this issue, this study focuses on the integration of SR-PBI-CT and helical acquisition mode (i.

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Tissue engineering offers a great potential in regenerative dentistry and to this end, three dimensional (3D) bioprinting has been emerging nowadays to enable the incorporation of living cells into the biomaterials (such a mixture is referred as a bioink in the literature) to create scaffolds. However, the bioinks available for scaffold bioprinting are limited, particularly for dental tissue engineering, due to the complicated, yet compromised, printability, mechanical and biological properties simultaneously imposed on the bioinks. This paper presents our study on the development of a novel bioink from carboxymethyl chitosan (CMC) and alginate (Alg) for bioprinting scaffolds for enamel tissue regeneration.

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To test the application effect of a self-developed mouth opener with a tongue base retractor in the operation of the deep part of tongue base. The tongue base surgical field was exposed by using a self-developed mouth opener with a tongue base retractor in 8 patients who underwent deep tongue base operation via oral approach, the difficulty of operation, the effect of exposure of operation field, the tear of mucous membrane of the pharynx arch and the risk of tongue paralysis were observed. The self-made mouth opener can expose the deep operative field of the tongue root by using the self-provided tongue root retractor during the operation, and the operation is conducted under the guidance of angle endoscope.

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In order to suppress the geometrical artifacts caused by random jitter in ray source scanning, and to achieve flexible ray source scanning trajectory and meet the requirements of task-driven scanning imaging, a method of free trajectory cone-beam computed tomography (CBCT) reconstruction is proposed in this paper. This method proposed a geometric calibration method of two-dimensional plane. Based on this method, the geometric calibration phantom and the imaging object could be simultaneously imaged.

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Distinguishing from other traditional imaging, synchrotron radiation microcomputed tomography (SR-μCT) imaging allows for the visualization of three-dimensional objects of interest in a nondestructive and/or way with better spatial resolution, deep penetration, relatively fast speed, and/or high contrast. SR-μCT has been illustrated promising for visualizing and characterizing tissue scaffolds for repairing or replacing damaged tissue or organs in tissue engineering (TE), which is of particular advance for longitudinal monitoring and tracking the success of scaffolds once implanted in animal models and/or human patients. This article presents a comprehensive review on recent studies of characterization of scaffolds based on SR-μCT and takes scaffold architectural properties, mechanical properties, degradation, swelling and wettability, and biological properties as five separate sections to introduce SR-μCT wide applications.

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Background: The objective of this study was to assess whether entecavir (ETV) in combination with interferon-α (IFN-α) could reduce hepatocellular cancer (HCC) and extrahepatic cancers (EHCs) in patients with chronic hepatitis B (CHB).

Methods: The cohort consisted of 4194 patients with CHB treated with ETV combined with IFN-α or ETV monotherapy at a tertiary hospital in Beijing, China, from January 2009 to December 2017. The risks, hazard ratios (HRs), and 95% confidence intervals (CIs) of HCC and EHCs were compared in the 2 groups.

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Introduction: The treatment evidence for entecavir-treated chronic hepatitis B (CHB) patients without maintaining of virologic response (MVR, defined as persistent HBV DNA <20 IU/mL during therapy) remains uncertain. We aimed to determine the relationship between non-MVR and hepatocellular carcinoma (HCC) risk in entecavir-treated CHB patients.

Methods: A cohort of 1447 entecavir-treated CHB patients were enrolled.

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PET image reconstruction from incomplete data, such as the gap between adjacent detector blocks generally introduces partial projection data loss, is an important and challenging problem in medical imaging. This work proposes an efficient convolutional neural network (CNN) framework, called GapFill-Recon Net, that jointly reconstructs PET images and their associated sinogram data. GapFill-Recon Net including two blocks: the Gap-Filling block first address the sinogram gap and the Image-Recon block maps the filled sinogram onto the final image directly.

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Stimuli-responsive biomaterials that contain logic gates hold great potential for detecting and responding to pathological markers as part of clinical therapies. However, a major barrier is the lack of a generalized system that can be used to easily assemble different ligand-responsive units to form programmable nanodevices for advanced biocomputation. Here we develop a programmable polymer library by including responsive units in building blocks with similar structure and reactivity.

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The mammography is the first choice of breast cancer screening, which has proven to be the most effective screening method. An antiscatter grid is usually employed to enhance the contrast of image by absorbing unexpected scattered signals. However, the grid pattern casts shadows and grid artifacts, which severely degrade the image quality.

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Small interfering RNAs (siRNAs) can selectively target and downregulate disease-causing genes, holding great promise in treating human diseases, especially malignant cancers. However, how to efficiently deliver siRNAs into target cell cytosol is a problem that has hindered their clinical application. Here, we review the recent strategies for siRNA delivery on the basis of smart nanocarriers by using stimuli-responsive materials.

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A new silicon based waveguide with full CMOS compatibility is developed to fabricate an on-chip Bragg cladding waveguide that has an oxide core surrounded by a high index contrast cladding layers. The cladding consists of several dielectric bilayers, where each bilayer consists of a high index-contrast pair of layers of Si and Si3N4. This new waveguide guides light based on omnidirectional reflection, reflecting light at any angle or polarization back into the core.

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