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SSRN 2024年

作者： Park, Chansun Elmughrabi, Abdallah Melis, Alima Cho, Shinhaeng Kim, Sangsu Yeom, Jung-Yeol Global Health Technology Research Center Korea University Seoul02841 Korea Republic of Department of Bioengineering Korea University Seoul02841 Korea Republic of Interdisciplinary Program in Precision Public Health Korea University Seoul02841 Korea Republic of Department of Radiation Oncology Chonnam National University Medical School Gwangju61469 Korea Republic of School of Biomedical Engineering Korea University Seoul02841 Korea Republic of

In this study, we developed Ce:GAGG ceramic scintillators (containing 5 × 5 × 2 mm3 Ce:GAGG single crystals) encapsulated by different light reflectors, namely, Teflon (400 μm), enhanced specular reflector (ESR) film (65 μm), and a titanium dioxide (TiO2) reflector with different thicknesses and measured their γ-ray spectra under irradiation by a 137Cs radioactive source. The reflectance of a 100-µm-thick (optimal thickness) TiO2 layer surpassed those of the other two counterparts and resulted in a high light-collection efficiency. In order to assess the temperature dependence of the reflectors, samples were heated up to 300 °C in air. The measured reflectance decreased with the increasing temperature, and the color of the reflector’s surface changed. The observed variations in the surface morphology, measured by scanning electron microscopy, corresponded to the determined reflectance of the TiO2 layer. Upon heating above 200 °C in air, the TiO2 layer decomposed into other oxides, with a simultaneous increase in its surface porosity. On the other hand, Ce:GAGG single crystal sample heated at 300 °C in vacuum showed only a negligible color variation, retained 80.3% of their initial reflectance, and exhibited an energy resolution of 12.8%. This implies that oxidation may be the cause of performance degradation, and a passivation layer may allow the use of reflectors at high temperatures. This was verified when a TiO2 layer covered with a heat-resistant epoxy exhibited comparable performance by isolating the reflecting from the air. The results obtained in this study suggest that a TiO2 layer can be used as a long-wavelength reflector in oxide and other types of scintillators for efficient radiation detection in harsh environments, including air-free environments, such as in aerospace, under vacuum conditions or when used in conjunction with a protective passivation layer. © 2024, The Authors. All rights reserved.

关键词： Titanium dioxide

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Microbiota-dependent early-life programming of gastrointestinal motility

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iScience 2024年第10期27卷 110895页

作者： Frith, Mary E. Kashyap, Purna C. Linden, David R. Theriault, Betty Chang, Eugene B. Interdisciplinary Scientist Training Program University of Chicago Chicago 60637 IL United States Department of Medicine University of Chicago Chicago 60637 IL United States Division of Gastroenterology and Hepatology Department of Medicine Mayo Clinic Rochester 55905 MN United States Enteric Neuroscience Program Department of Physiology and Biomedical Engineering Mayo Clinic Rochester 55905 MN United States Department of Surgery University of Chicago Chicago 60637 IL United States

Gastrointestinal microbes modulate peristalsis and stimulate the enteric nervous system (ENS), whose development, as in the central nervous system (CNS), continues into the murine postweaning period. Given that adult CNS function depends on stimuli received during critical periods of postnatal development, we hypothesized that adult ENS function, namely motility, depends on microbial stimuli during similar critical periods. We gave fecal microbiota transplantation (FMT) to germ-free mice at weaning or as adults and found that only the mice given FMT at weaning recovered normal transit, while those given FMT as adults showed limited improvements. RNA sequencing (RNA-seq) of colonic muscularis propria revealed enrichments in neuron developmental pathways in mice exposed to gut microbes earlier in life, while mice exposed later—or not at all—showed exaggerated expression of inflammatory pathways. These findings highlight a microbiota-dependent sensitive period in ENS development, pointing to potential roles of the early-life microbiome in later-life dysmotility. © 2024 The Author(s)

关键词： Developmental neuroscience Microbiome Neuroscience

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Complexity Analysis based on Parietal Fuzzy Entropy to Facilitate ADHD Diagnosis in Young Children

Complexity Analysis based on Parietal Fuzzy Entropy to Facil...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： I-Wen Huang Yu-Ci Jheng I-Chun Chen Li-Wei Ko Institute of Biomedical Engineering National Yang Ming Chiao Tung University Hsinchu Taiwan Institute of Electrical and Control Engineering National Yang Ming Chiao Tung University Hsinchu Taiwan International Program in Interdisciplinary Neuroscience College of Biological Science and Technology National Yang Ming Chiao Tung University Hsinchu Taiwan Department of Physical Medicine and Rehabilitation Ton-Yen General Hospital Hsinchu Taiwan Drug Development and Value Creation Research Center Kaohsiung Medical University Kaohsiung Taiwan

ISBN: (数字)9798350371499

ISBN: (纸本)9798350371505

Attention deficit hyperactivity disorder (ADHD) is the most common condition affecting the development of neurons in children. Therefore, early and accurate diagnosis of ADHD in young children is of paramount importance. In this study, the 8-channel wireless wearable EEG measurement device was employed to record EEG data from 30 children diagnosed with ADHD and 30 typical development (TD) young children aged 4-7 years. The data was collected both during rest and while the children performed a Kiddie Continuous Performance Test (K-CPT). We extract relative power spectral density (PSD) unaffected by factors like skull resistance and thickness. Additionally, a range of complex entropy values based on the time domain were extracted. These included sample entropy (SaEn), permutation entropy (PeEn), singular value decomposition entropy (SvdEn), and fuzzy entropy (FuEn). We compare the performance of k-Nearest Neighbors (kNN), Support Vector Machine (SVM), and XGBoost, and utilized the sequential forward selection (SFS) feature selection method in the wrapper approach. Through this process, the study identified the most effective EEG data segments and feature subsets. The findings indicated that using a combination of resting and K-CPT EEG data yielded greater discriminability. Notably, the study found that extracting beta power from the right occipital lobe along with fuzzy entropy from the parietal lobe resulted in optimal accuracy of 90% in distinguishing between children with ADHD and TD children. These outcomes highlight the potential of relative PSD and complexity metrics to support the clinical diagnosis of early ADHD. Furthermore, these metrics may contain unique neurobiomarkers that could be valuable for devising early intervention strategies.

关键词： Support vector machines Performance evaluation Pediatrics Accuracy Aging Feature extraction Entropy Electroencephalography Complexity theory Time-domain analysis

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Melanoma Detection by AFM Indentation of Histological Specimens

Research Square

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Research Square 2021年

作者： Jeon, ByoungJun Jung, Hyo Gi Lee, Sang Won Lee, Gyudo Shim, Jung Hee Kim, Mi Ok Kim, Byung Jun Kim, Sang-Hyon Lee, Hyungbeen Lee, Sang Woo Yoon, Dae Sung Jo, Seong Jin Choi, Tae Hyun Lee, Wonseok Interdisciplinary Program for Bioengineering Seoul National University Seoul08826 Korea Republic of School of Biomedical Engineering Korea University Seoul02841 Korea Republic of Interdisciplinary Program in Precision Public Health Korea University Seoul02841 Korea Republic of Department of Biotechnology and Bioinformatics Korea University Sejong30019 Korea Republic of Department of Plastic and Reconstructive Surgery Research Services Seoul National University Bundang Hospital Seongnam13620 Korea Republic of Department of Plastic and Reconstructive Surgery Institute of Human Environment Interface Biology Seoul National University College of Medicine Seoul03087 Korea Republic of Department of Internal Medicine Keimyung University Dongsan Medical Center Daegu41931 Korea Republic of Department of Biomedical Engineering Yonsei University Wonju26493 Korea Republic of R&D Center of Curigin Ltd. Seoul04778 Korea Republic of Department of Dermatology Seoul National University College of Medicine Seoul03087 Korea Republic of Department of Electrical Engineering Korea National University of Transportation Chungju27469 Korea Republic of

Melanoma is visible unlike other types of cancer, but it is still challenging to diagnose correctly because of the difficulty in distinguishing between benign nevus and melanoma. We conducted a robust investigation of melanoma, identifying considerable differences in local elastic properties between nevus and melanoma tissues by using atomic force microscopy (AFM) indentation of histological specimens. Specifically, the histograms of the elasticity of melanoma displayed multimodal Gaussian distributions, exhibiting the heterogeneous mechanical properties, in contrast with the unimodal distributions of elasticity in the benign nevus. We identified this notable signature was consistent regardless of blotch incidence by sex, age, anatomical site (e.g., thigh, calf, arm, eyelid, and cheek), or cancer stage (I, IV, and V). In addition, we found that the non-linearity of the force-distance curves for melanoma is increased compared to benign nevus. We believe that AFM indentation of histological specimens may technically complement conventional histopathological analysis for earlier and more precise melanoma detection. © 2021, CC BY.

关键词： Elasticity

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Modulation of Foreign Body Reaction against PDMS Implant by Grafting Topographically Different Poly(Acrylic Acid) Micropatterns

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SSRN 2019年

作者： Lee, Jae Sang Shin, Byung Ho Yoo, Byoung Yong Nam, Sun-Young Lee, Miji Park, Hansoo Choy, Young Bin Heo, Chan Yeong Koh, Won-Gun Department of Chemical and Biomolecular Engineering Yonsei University Seoul03722 Korea Republic of Department of Biomedical Engineering College of Medicine Seoul National University Seoul03080 Korea Republic of Interdisciplinary Program for Bioengineering College of Engineering Seoul National University Seoul08826 Korea Republic of Institute of Medical & Biological Engineering Medical Research Center Seoul National University Seoul03080 Korea Republic of Department of Plastic and Reconstructive Surgery College of Medicine Seoul National University Seoul03080 Korea Republic of Department of Plastic and Reconstructive Surgery Seoul National University Bundang Hospital Seongnam13620 Korea Republic of School of Integrative Engineering Chung-Ang University Korea Republic of

The surface of poly(dimethylsiloxane) (PDMS) was grafted with poly(acrylic acid) (PAA) layers via surface-initiated photopolymerization to suppress the capsular contracture resulting from a foreign body reaction. Owing to the nature of photo-induced polymerization, various PAA micropatterns could be fabricated using photolithography. Hole and stripe micropatterns approximately 100-μm wide and 3-μm thick were grafted onto the PDMS surface without delamination. The incorporation of PAA micropatterns provided not only chemical cues by hydrophilic PAA microdomains but also topographical cues by hole or stripe micropatterns. In vitro studies revealed that a PAA-grafted PDMS surface had a lower proliferation of both macrophages and fibroblasts regardless of the pattern presence. However, PDMS with PAA micropatterns, especially stripe micropatterns, minimized the aggregation of fibroblasts and their subsequent differentiation into myofibroblasts. An in vivo study also showed that PDMS samples with stripe micropatterns polarized macrophages into anti-inflammatory M2 macrophages and most effectively inhibited capsular contracture, which was demonstrated by investigating the inflammation score, transforming-growth-factor-β expression, number of macrophages, and myofibroblasts as well as the collagen density and capsule thickness. © 2019, The Authors. All rights reserved.

关键词： Macrophages

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Inorganic Ions Activate Lineage-Specific Gene Regulatory Networks to Drive Stem Cells Differentiation

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SSRN 2023年

作者： Kersey, Anna L. Gaharwar, Akhilesh K. Singh, Irtisha Department of Biomedical Engineering College of Engineering Texas A&M University College StationTX77843 United States Department of Cell Biology and Genetics College of Medicine Texas A&M University College StationTX77843 United States Interdisciplinary Program in Genetics Texas A&M University College StationTX77843 United States Center for Remote Health Technologies and Systems Texas A&M University College StationTX77843 United States Department of Material Science and Engineering Dwight Look College of Engineering Texas A&M University College StationTX77843 United States

Ions released from inorganic biomaterials play a vital role in defining cell identity. However, the effect of inorganic ions on cellular functions has yet to be investigated at the transcriptomic level, representing a critical knowledge gap in the development of next-generation of bioactive materials. To address this gap, we investigated the impact of various inorganic ions including silver, copper, titanium, and platinum on human stem cells. Our finding showed that silver and copper induce osteogenic and chondrogenic differentiation respectively, through enrichment of ion-dependent signaling pathways. Specifically, silver effectively induced Wnt and MAPK signaling, which are vital for osteogenesis. On the other hand, copper specifically stimulated TGFβ signaling, while suppressing JAK-STAT signaling, thereby promoting chondrogenesis. In contrast, platinum, tantalum, and titanium ions didn't stimulate regenerative responses. Titanium displayed minimal gene expression changes, demonstrating its relative inertness, while platinum and tantalum induced oxidative stress. These findings are further supported by gene and protein level validation using traditional techniques. Together, our findings highlight the potential of inorganic biomaterials in revolutionizing tissue regeneration strategies, which currently rely largely on growth factors and small molecule therapeutics. © 2023, The Authors. All rights reserved.

关键词： Stem cells

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Endoscopic Vision Based Tracking of Multiple Surgical Instruments in Robot-assisted Surgery

Endoscopic Vision Based Tracking of Multiple Surgical Instru...

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International Conference on Control, Automation and Systems

作者： Jiwon Ryu Jaesoon Choi Hee Chan Kim Interdisciplinary Program Bioengineering Major Graduate School Seoul National University Asan Institute for Life Sciences University of Ulsan College of Medicine and Asan Medical Center Department of Biomedical Engineering College of Medicine and Institute of Medical and Biological Engineering Medical Research Center Seoul National University

ISBN: (纸本)9781467322478

Robot-assisted cardiac surgeries are effective for operations in limited spaces. Enhancement in safety functions based on automatic tracking of surgical instrument position to prevent inadvertent harmful events as cardiac tissue perforation and instrument collisions can be meaningful augmentation to current robot surgery system. A vision based instrument tracking scheme as a core algorithm to implement such assistive functions has been developed in this study. Through a chain of computer vision techniques, including classification of metallic properties using k-means clustering and instrument movement tracking using similarity measure, Euclidean distance calculation, and Kalman filter algorithm, an automatic tracking scheme has been proposed and the implemented system showed satisfactory performance in tests using real robot-assisted surgery videos. Trajectory comparisons of automatically detected data and ground truth data obtained by manually locating the center of mass of each instrument were used to quantitatively validate the system. The developed algorithm could provide valuable information to clinicians for safer operation.

关键词： Surgical instrument tracking Robot-assisted Surgery Multiple object tracking Collision warning

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Surface enhancements accelerate bone bonding to CPC-coated strain gauges†

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Journal of biomedical Materials Research Part B: Applied Biomaterials 2001年第1期56卷

作者： Nicholas M. Cordaro John A. Szivek Don W. DeYoung Orthopaedic Research Laboratory Department of Orthopedic Surgery and Biomedical Engineering Interdisciplinary Program University of Arizona Tucson Arizona 85724 University Animal Care University of Arizona Tucson Arizona 85721

Calcium phosphate ceramic (CPC)-coated strain gauges have been used for in vivo bone strain measurements for up to 18 weeks, but they require 6 to 9 weeks for sufficient bonding. Osteogenic protein-1 (OP-1), PepTite™ (a proprietary ligand), calcium sulfate dihydrate (CSD), transforming growth factor β-1 (TGF-β1 ), and an endothelial cell layer with and without TGF-β1 were used as surface enhancements to accelerate bone-to-CPC bonding. Young male Sprague–Dawley rats were implanted with unenhanced and enhanced CPC-coated gauges. Animals were allowed normal activity for 3 weeks and then calcein labeled. Femurs were explanted following euthanasia. A gauge was attached with cyanoacrylate to the opposite femur in the same position as the CPC-coated gauge. Bones were cantilever-loaded to assess strain transfer. They were sectioned and stained with mineralized bone stain (MIBS) and examined with transmitted and ultraviolet light. Mechanical testing indicated increased sensing accuracy for TGF-β1 and OP-1 enhancements to 105 ± 14% and 92 ± 12% versus 52 ± 44% for the unenhanced gauges. The PepTite™ and the endothelial-cell-layer-enhanced gauges showed lower sensing accuracy, and histology revealed a vascular layer near CPC particles. TGF-β1 increased bone formation when used prior to endothelial cell sodding. CSD prevented strain transfer to the femur. TGF-β1 and OP-1 surface enhancements produced accurate in vivo strain sensing on the rat femur after 3 weeks. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 109–119, 2001

关键词： strain gauge calcium phosphate ceramics transforming growth factor β-1 osteogenic protein-1 endothelial cells

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Dopaminergic and Serotoninergic Neurotoxicity of Lanthanide Phosphate (Tbpo4) in Developing Zebrafish

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SSRN 2023年

作者： Chen, Siying Wang, Xiaohong Ye, Xiaolin Qin, Yingju Wang, Haiqing Liang, Zhenda Zhu, Lishan Zhou, Li Martyniuk, Christopher J. Yan, Bing Institute of Environ. Res. at Greater Bay Area Key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of Education Guangzhou University Guangzhou510006 China Center for Environmental and Human Toxicology Department of Physiological Sciences College of Veterinary Medicine UF Genetics Institute Interdisciplinary Program in Biomedical Sciences in Neuroscience University of Florida GainesvilleFL32611 United States School of Environmental Science and Engineering Shandong University Shandong Jinan250100 China

Rare earth elements (REEs) are exploited for global use in manufacturing. Such activities result in their release into the environment and the transformation into more stable phosphate deposition. The objective of this study was to evaluate molecular and behavioral changes of zebrafish exposed to the synthesized terbium phosphate (TbPO4) at concentrations of 10, 20, and 50 mg/L and to determine its potential for neurotoxicity. Metabolomic profiling and assessment of transcripts and proteins were conducted to uncover the molecular mechanisms underlying TbPO4 with emphasis on neurotransmitter systems. Exposure to 20 mg/L TbPO4 induced larval hyperactivity and perturbed the cholinergic system in zebrafish. Based on metabolomics, dopamine (DA), serotonin (5-HT), and many of their precursors and metabolites were decreased in abundance by TbPO4. In addition, the expression levels of transcripts related to the synthesis, transport, receptor binding, and metabolism of DA and 5-HT were analyzed at the mRNA and protein levels. Transcript and protein levels for tyrosine hydroxylase (TH), the rate-limiting enzyme for DA synthesis, were down-regulated in larval fish. Monoamine oxidase (MAO), an enzyme that catabolizes monoamines DA and 5-HT, also reduced mRNA abundance. We hypothesize that DA synthesis and monoamine metabolism are associated with behavioral alterations. In addition, a mechanism for the disruption of neurotransmitter systems by TbPO4 may be the apoptosis of neurons. This study elucidates putative mechanisms and exposure risks to wildlife and humans by characterizing phosphatic REE-induced neurotoxicity in developing zebrafish. © 2023, The Authors. All rights reserved.

关键词： Rare earth elements

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Biomaterials: Nanowell-Trapped Charged Ligand-Bearing Nanoparticle Surfaces: A Novel Method of Enhancing Flow-Resistant Cell Adhesion (Adv. Healthcare Mater. 7/2013)

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Advanced Healthcare Materials 2013年第7期2卷

作者： Phat L. Tran Jessica R. Gamboa Katherine E. McCracken Mark R. Riley Marvin J. Slepian Jeong-Yeol Yoon Biomedical Engineering Graduate Interdisciplinary Program and Department of Biomedical Engineering The University of Arizona Tucson Arizona 85721 USA Department of Agricultural and Biosystems Engineering The University of Arizona Tucson Arizona 85721 USA Sarver Heart Center and Department of Medicine College of Medicine The University of Arizona Tucson Arizona 85721 USA

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