Diagnosis of Crohn's disease and ulcerative colitis using the microbiome.

BACKGROUND: Inflammatory bowel disease (IBD) is a multifactorial chronic inflammatory disease resulting from dysregulation of the mucosal immune response and gut microbiota. Crohn's disease (CD) and ulcerative colitis (UC) are difficult to distinguish, and differential diagnosis is essential for establishing a long-term treatment plan for patients. Furthermore, the abundance of mucosal bacteria is associated with the severity of the disease. This study aimed to differentiate and diagnose these two diseases using the microbiome and identify specific biomarkers associated with disease activity. RESULTS: Differences in the abundance and composition of the microbiome between IBD patients and healthy controls (HC) were observed. Compared to HC, the diversity of the gut microbiome in patients with IBD decreased; the diversity of the gut microbiome in patients with CD was significantly lower. Sixty-eight microbiota members (28 for CD and 40 for UC) associated with these diseases were identified. Additionally, as the disease progressed through different stages, the diversity of the bacteria decreased. The abundances of Alistipes shahii and Pseudodesulfovibrio aespoeensis were negatively correlated with the severity of CD, whereas the abundance of Polynucleobacter wianus was positively correlated. The severity of UC was negatively correlated with the abundance of A. shahii, Porphyromonas asaccharolytica and Akkermansia muciniphilla, while it was positively correlated with the abundance of Pantoea candidatus pantoea carbekii. A regularized logistic regression model was used for the differential diagnosis of the two diseases. The area under the curve (AUC) was used to examine the performance of the model. The model discriminated UC and CD at an AUC of 0.873 (train set), 0.778 (test set), and 0.633 (validation set) and an area under the precision-recall curve (PRAUC) of 0.888 (train set), 0.806 (test set), and 0.474 (validation set). CONCLUSIONS: Based on fecal whole-metagenome shotgun (WMS) sequencing, CD and UC were diagnosed using a machine-learning predictive model. Microbiome biomarkers associated with disease activity (UC and CD) are also proposed.

First Detection of Enterovirus D68 in Korean Children, September 2022.

BACKGROUND: Enterovirus D68 (EV-D68) is a re-emerging pathogen that is particularly common in children and may cause asthma-like respiratory infection and acute flaccid myelitis. However, in Korea, EV-D68 has never been reported thus far. This study aimed to identify EV-D68 from nasopharyngeal aspirates (NPAs) in Korean children with a respiratory tract infection. MATERIALS AND METHODS: The EV-D68 reference strain was purchased and blindly used to assess the detection ability of three commercial and one in-house mRT-PCR kit in 2018. Then, we selected children whose specimens were positive for human rhinovirus (HRV) and/or enterovirus (EV) by Allplex mRT-PCR (Seegene, Inc., Seoul, Korea) from April to December 2022. Total RNA was extracted from NPAs, and a partial 5'-UTR gene was amplified and sequenced for the identification of HRV/EV species. Additionally, PCR targeting the VP1 gene was performed to assess EV-D68-positive NPAs, followed by sequencing. Phylogenetic analysis and comparison of amino acid sequence alignments were performed using a partial VP1 gene of our and recent international EV-D68 strains. RESULTS: Among the mRT-PCR kits tested, only the in-house kit was able to detect EV-D68 in 2018. However, we detected three EV-D68 strains among children hospitalized with fever and/or respiratory symptoms in September - December 2022 who tested positive for EV by the Allplex kit. Two of them were healthy toddlers with lower respiratory infections accompanied by new-onset wheezing but no neurologic complications. Among 34 children with lower respiratory infection who tested positive for HRV during the same period, EV-D68 was not detected. Phylogenetic analysis revealed that the first Korean EV-D68 belonged to subclade B3. Amino acid sequence alignment of international subclade B3 EV-D68 strains also showed that our strain is genetically more related to those from Europe than those from Japan. CONCLUSION: We first detected EV-D68 in three Korean children who had EV detected by the Allplex mRT-PCR kit in 2022. EV-D68 also circulated in Korea in fall 2022, but the prevalence and severity seemed to be lower than those in previous reports from other countries.

The emergence of remote laboratory courses in an emergency situation: University instructors' agency during the COVID-19 pandemic.

This study examines and describes how various online remote laboratory courses, necessitated by the COVID-19 pandemic, were implemented at Hankuk University in Korea in 2020. We compared four general undergraduate laboratory courses, one each for physics, chemistry, biology, and earth science, and two major-level laboratory courses taught during the spring and fall of 2020. Employing a sociocultural perspective, we examined how the changes in structures at the macro-, meso-, and micro-levels shaped the responses of educational authorities and impacted the agency of university instructors. Instructors implemented various remote laboratory courses in each content area dependent upon availability and access to material resources, including access to video of laboratory activities, and also based on the nature of experimental data associated with each content area. Drawing from survey responses and in-depth interviews with instructors and students, we share findings about how instructor practices impacted the interactions of students, the processes for evaluation, and student learning. We discuss how the global pandemic has re-ignited the debate about the role and value of experimental laboratory activities for undergraduate science majors and about the significance of hands-on versus minds-on science learning. Implications for how universities approach laboratory coursework in the post-COVID-19 are discussed, and questions for university science instruction are raised for future research.

Navigating into the future of science museum education: focus on educators' adaptation during COVID-19.

Repeated closures of the world's science museums to stem the spread of COVID-19 have significantly reduced visitors' access to informal science learning opportunities. Interviews with educators and an analysis of the online content of a science museum were used in this case study to examine the impact of this phenomenon on informal science education. We present several education examples to highlight how educators have attempted to adapt. Specifically, we describe and characterize educators' strategies-collaboration, networking, and feedback-to address difficulties involved in developing virtually accessible content that will engage users. In addition, we analyze essential attributes of informal learning in the science museum attributes of interaction, free-choice learning, hands-on experience, and authentic learning that the educators kept in mind while planning and redesigning educational programs and cultural events in response to COVID-19. We conclude by forecasting the future of science museums based on the educators' perceptions of their roles and the nature of informal science learning, assuming that educators are the crucial agents to build a new future direction.

Exploring informal science education responses to COVID-19 global pandemic: learning from the case of the Gwacheon National Science Museum in Korea.

Science museums have long been heralded as important informal science education sites where people can engage in voluntary and experiential science learning. In this paper, we identify and raise questions about how science museum responses to a global pandemic could impact on accessibility of informal science education for the public. To explore these issues, we examined the response of the Gwacheon National Science Museum (GNSM) to COVID-19 in South Korea using publicly available data from the museum website and museum YouTube video channel. Analysis shows that the pandemic has increased and diversified the GNSM's provision of science content for the general public via online platforms, such as YouTube and the museum website. In addition, GNSM educators are preparing special outreach education projects for deaf and blind visitors, who have often been excluded from informal science learning opportunities. By discussing these changes, we seek to raise questions about the potential for a global pandemic, like COVID-19, to affect informal science learning opportunities for a diverse group of people.

Heparin-Mimicking Polymer-Based In Vitro Platform Recapitulates In Vivo Muscle Atrophy Phenotypes.

The cell-cell/cell-matrix interactions between myoblasts and their extracellular microenvironment have been shown to play a crucial role in the regulation of in vitro myogenic differentiation and in vivo skeletal muscle regeneration. In this study, by harnessing the heparin-mimicking polymer, poly(sodium-4-styrenesulfonate) (PSS), which has a negatively charged surface, we engineered an in vitro cell culture platform for the purpose of recapitulating in vivo muscle atrophy-like phenotypes. Our initial findings showed that heparin-mimicking moieties inhibited the fusion of mononucleated myoblasts into multinucleated myotubes, as indicated by the decreased gene and protein expression levels of myogenic factors, myotube fusion-related markers, and focal adhesion kinase (FAK). We further elucidated the underlying molecular mechanism via transcriptome analyses, observing that the insulin/PI3K/mTOR and Wnt signaling pathways were significantly downregulated by heparin-mimicking moieties through the inhibition of FAK/Cav3. Taken together, the easy-to-adapt heparin-mimicking polymer-based in vitro cell culture platform could be an attractive platform for potential applications in drug screening, providing clear readouts of changes in insulin/PI3K/mTOR and Wnt signaling pathways.

Nanofabrication of bio-self assembled monolayer and its electrochemical property for toxicant detection.

Cyclic voltammetry (CV) has been used to investigate the electrochemical behavior of a glutathione (GSH) self assembled monolayer on modified gold electrodes (Bio-SAM). The GSH monolayer exhibits an influence on electrode surface activity. Electrochemically immobilized dsDNA onto a Cyt c/GSH-SAM/Au electrode, which is useful for the fabrication of a nanobiosensing device. The immobilized Cyt c followed by dsDNA immobilized films maintained its surface activity and finally dsDNA/Cyt c/GSH-SAM/Au electrode, targeted for the detection of toxicants. The films were characterized by CV, DPV, and AFM. The differential pulse voltammetry (DPV) technique was applied to detect three kinds of common toxins, 2-aminoanthracene (2-AA), 3-bromobenzanthrone (3-BBA) and bisphenol A (BPhA). The electrochemical signals showed good inverse relationship with the increase of concentrations of toxicants. Our proposed system based on electrochemical method with nanoscale film technology can be applied at highly sensitive biosensor for detecting various toxic chemicals.

Charge retention of self-assembled ferredoxin monolayer by the reduction-oxidation control for biomemory device.

The oxidation-reduction control to store charges in self-assembled ferredoxin layer was investigated by scanning electrochemical method. Micro sized spot arrays consisting of ferredoxin proteins which used as the storage element were formed on chemically modified gold coated glass by micro contanct printing method. The formation of ferredoxin array was confirmed by the atomic force microscopy. The charge store was investigated by external applied reduction potential to ferredoxin as a write function, and the stored reducing charge was measured as a read function of storage applications. In the reduction state, the stored charge was maintained for around 90 sec. This ferredoxin layer can be used as the molecular size information storage by applying the reducing potential and measuring the current flow when achieving the current of individual ferredoxin molecule.

Signal enhancement of surface plasmon resonance based immunosensor using gold nanoparticle-antibody complex for beta-amyloid (1-40) detection.

Numerous studies have indentified that beta-amyloid (1-40) in cerebrospinal fluid as a potential biomarker for Alzheimer's disease. In order for early detection of the Alzheimer's disease, an ultrasensitive diagnostic tool is required. In this study, an ultrasensitive surface plasmon resonance (SPR) based immunosensor for beta3-amyloid (1-40) was developed and its signal enhanced (1-40) with a gold (Au) nanoparticle-antibody complex. Antibodies to beta3-amyloid (1-40) were immobilized on the Au surface leading to a highly efficient immunoreaction due to the fact the paratope of the antibody faced in the opposite direction to the solid surface. The surface morphology of the bio-surface was investigated by using scanning tunneling microscopy (STM). The binding process of antibody fragments to the Au surface, target analytes, and Au nanoparticle-antibody complexes were monitored using SPR. The plot of SPR angle difference versus beta3-amyloid (1-40) concentration shows a linear correlation over a concentration range of nine orders of magnitude, having a detetion limit up to 1 fg/ml.

Electrical detection of beta-amyloid (1-40) using scanning tunneling microscopy.

Numerous studies have shown that the presence of beta-amyloid (1-40) in cerebrospinal fluid can be used as a potential biomarker for Alzheimer's disease. Identifying biomarkers for Alzheimer's disease is highly important because these biomarkers could be used to establish the diagnosis before the disease reaches clinical severity. In this study, a vertically configured electrical detection system associated with scanning tunneling microscopy (STM) was used to characterize antigen-antibody binding interactions. The proposed technique can be easily utilized to construct a multiple measurement system in a protein chip. The immunocomplexes used in the model protein comprise beta-amyloid (1-40), corresponding antibody fragments, and gold nanoparticle-antibody conjugates. The electrical tunneling current between the STM tip and these complexes exhibited a peak-like pulse, where the frequency of these pulses was dependent on the surface density of bound complexes. Hence, a quantitative measurement of beta-amyloid concentration from a periodogram analysis of peak frequency was successfully achieved at concentrations as low as 1fg/mL.

Ultra-sensitive immunosensor for beta-amyloid (1-42) using scanning tunneling microscopy-based electrical detection.

An ultra-sensitive immunosensor for beta-amyloid is crucial because beta-amyloid is an important challenging marker to detect for early diagnosis of Alzheimer's disease. In this study, a vertically configured electrical detection system was developed based on scanning tunneling microscopy (STM) to detect antigen-antibody binding events. This technique could be used to easily construct a multiple measurement system in a biochip. We utilized immunocomplexes comprised of the model protein, beta-amyloid (1-42), corresponding antibody fragments, and gold (Au) nanoparticles-antibody conjugates for an immunosensor for Alzheimer's disease. The electrical tunneling current between the STM tip and these complexes exhibited a peak-like pulse, the frequency of which depended on the density of the bound complexes on the surface. We could therefore quantitatively measure beta-amyloid (1-42) concentrations as low as 10fg/mL using periodogram analysis of the peak frequency. Since this method accurately quantified much smaller amounts of beta-amyloid (1-42) than traditional immunosensors, this system shows promise as an ultra-sensitive immunodetection method.

Analysis of direct immobilized recombinant protein G on a gold surface.

For the immobilization of IgG, various techniques such as chemical linker, thiolated protein G methods, and fragmentation of antibodies have been reported [Y.M. Bae, B.K. Oh, W. Lee, W.H. Lee, J.W. Choi, Biosensors Bioelectron. 21 (2005) 103; W. Lee, B.K. Oh, W.H. Lee, J.W. Choi, Colloids Surf. B-Biointerfaces, 40 (2005) 143; A.A. Karyakin, G.V. Presnova, M.Y. Rubtsova, A.M. Egorov, Anal. Chem. 72 (2000) 3805]. Here, we modified the immunoglobulin Fc-binding B-domain of protein G to contain two cysteine residues at its C-terminus by a genetic engineering technique. The resulting recombinant protein, RPGcys, retained IgG-binding activity in the same manner as native protein G. RPGcys was immobilized on a gold surface by strong affinity between thiol of cysteine and gold. The orientations of both IgG layers immobilized on the base recombinant protein Gs were analyzed by fluorescence microscope, atomic force microscope (AFM), and surface plasmon resonance (SPR). Our data revealed that IgG-binding activity of RPGcys on gold surface significantly increased in comparison to wild type of protein G (RPGwild), which was physically adsorbed due to absence of cysteine residue. Immobilization of highly oriented antibodies based on cysteine-modified protein G could be useful for the fabrication of immunosensor systems.

Surface morphology and interdiffusion of LiF in Alq3-based organic light-emitting devices.

Highly efficient organic light-emitting devices (OLEDs) have been realized by insertion of a thin insulating lithium fluoride (LiF) layer between aluminum (Al) cathode and an electron transport layer, tris-(8-hydroxyquinoline) aluminum (Alq(3)). In this paper, we study the surface morphology of LiF on Alq(3) by synchrotron X-ray scattering and atomic force microscopy (AFM) as a function of thickness of LiF. We also study the interdiffusion of LiF into Al cathode as well as into Alq(3) layer as a function of temperature. Initially, LiF molecules are distributed randomly as clusters on the Alq(3) layer and then gradually form a layer as increasing LiF thickness. The interdiffusion of LiF into Al occurs more actively than into Alq(3) in annealing process. LiF on Alq(3) induces the ordering of Al to (111) direction strongly with increasing LiF thickness.