Synthesis and Isolation of a Homochiral Nanohoop Composed of a Tröger's Base and Hexaparaphenylene

The synthesis of a new nanohoop containing a stereogenic Tröger's base skeleton tethered to a curved hexaparaphenylene ([6]CPP) is reported. The TB[6]CPP nanohoop possesses a stable C2 symmetrical structure, which promotes the allowed transition that gives rise to pale blue emission with a quantum yield of ~0.69, surpassing the value of the more symmetrical [8]CPP. Moreover, TB[6]CPP shows chiroptical properties including circular dichroism and circularly polarized luminescence with a moderate dissymmetry factor (|glum|) of ~2.1×10-3.

Growth control of Marchantia polymorpha gemmae using nonthermal plasma irradiation

Several studies have documented that treatment by cold atmospheric pressure plasma (CAPP) on plants foster seed germination and growth in recent years. However, the molecular processes that underlie the action of CAPP on the seeds and plants remain mostly enigmatic. We here introduce gemmae of Marchantia polymorpha, a basal liverwort, as a novel model plant material suitable for CAPP research. Treating the gemmae with CAPP for a constant time interval at low power resulted in consistent growth enhancement, while growth inhibition at higher power in a dose-dependent manner. These results distinctly demonstrate that CAPP irradiation can positively and negatively regulate plant growth depending on the plasma intensity of irradiation, offering a suitable experimental system for understanding the molecular mechanisms underlying the action of CAPP in plants.

Functional and structural analysis of a cyclization domain in a cyclic β-1,2-glucan synthase

Cyclic β-1,2-glucan synthase (CGS) is a key enzyme in production of cyclic β-1,2-glucans (CβGs) which are involved in bacterial infection or symbiosis to host organisms. Nevertheless, a mechanism of cyclization, the final step in the CGS reaction, has not been fully understood. Here we performed functional and structural analyses of the cyclization domain of CGS alone from Thermoanaerobacter italicus (TiCGSCy). We first found that β-glucosidase-resistant compounds are produced by TiCGSCy with linear β-1,2-glucans as substrates. The 1H-NMR analysis revealed that these products are CβGs. Next, action pattern analyses using β-1,2-glucooligosaccharides revealed a unique reaction pattern: exclusive transglycosylation without hydrolysis and a hexasaccharide being the minimum length of the substrate. These analyses also showed that longer substrate β-1,2-glucooligosaccharides are preferred, being consistent with the fact that CGSs generally produce CβGs with degrees of polymerization of around 20. Finally, the overall structure of the cyclization domain of TiCGSCy was found to be similar to those of β-1,2-glucanases in phylogenetically different groups. Meanwhile, the identified catalytic residues indicated clear differences in the reaction pathways between these enzymes. Overall, we propose a novel reaction mechanism of TiCGSCy. Thus, the present group of CGSs defines a new glycoside hydrolase family, GH189. KEY POINTS: • It was clearly evidenced that cyclization domain alone produces cyclic β-1,2-glucans. • The domain exclusively catalyzes transglycosylation without hydrolysis. • The present catalytic domain defines as a new glycoside hydrolase family 189.

Preparation of gold nanoparticles using low-temperature heating of the dry residue of a droplet of an HAuCl4 solution in air

In the present study, by heating a quartz glass substrate having the dry residue of a 10 μL droplet of a solution of HAuCl4 and a counter substrate facing to the dry residue from room temperature to one hundred and several tens of degrees Celsius in 20 min in air, highly dense gold nanoparticles were produced on the counter substrate. A gold nanoparticle substrate produced by this simple method was utilized as a substrate for surface-enhanced Raman scattering analysis.

Transcriptome analysis of the cerebral cortex of acrylamide-exposed wild-type and IL-1β-knockout mice

Acrylamide is an environmental electrophile that has been produced in large amounts for many years. There is concern about the adverse health effects of acrylamide exposure due to its widespread industrial use and also presence in commonly consumed foods and others. IL-1β is a key cytokine that protects the brain from inflammatory insults, but its role in acrylamide-induced neurotoxicity remains unknown. We reported recently that deletion of IL-1β gene exacerbates ACR-induced neurotoxicity in mice. The aim of this study was to identify genes or signaling pathway(s) involved in enhancement of ACR-induced neurotoxicity by IL-1β gene deletion or ACR-induced neurotoxicity to generate a hypothesis mechanism explaining ACR-induced neurotoxicity. C57BL/6 J wild-type and IL-1β KO mice were exposed to ACR at 0, 12.5, 25 mg/kg by oral gavage for 7 days/week for 4 weeks, followed by extraction of mRNA from mice cerebral cortex for RNA sequence analysis. IL-1β deletion altered the expression of genes involved in extracellular region, including upregulation of PFN1 gene related to amyotrophic lateral sclerosis and increased the expression of the opposite strand of IL-1β. Acrylamide exposure enhanced mitochondria oxidative phosphorylation, synapse and ribosome pathways, and activated various pathways of different neurodegenerative diseases, such as Alzheimer disease, Parkinson disease, Huntington disease, and prion disease. Protein network analysis suggested the involvement of different proteins in related to learning and cognitive function, such as Egr1, Egr2, Fos, Nr4a1, and Btg2. Our results identified possible pathways involved in IL-1β deletion-potentiated and ACR-induced neurotoxicity in mice.

Derivatization procedure of estradiol with a combination of MPDNP-F and 4-dimethylaminopyridine to generate product ion containing estradiol-skeleton for reliable determination of its serum/plasma concentrations by LC/ESI-MS/MS

The quantification of serum/plasma estradiol (E2) is useful for the diagnosis, pathological analysis, and monitoring of the therapeutic efficacy of estrogen-dependent diseases. In this study, an improved derivatization method using 1-(2,4-dinitro-5-fluorophenyl)-4,4-dimethylpiperazinium iodide (MPDNP-F) was developed and combined with liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) for the sensitive and specific quantification of the serum/plasma E2. In the new method, the reaction time was reduced to 15 min from 90 min (two-step reaction in the previous method) by the direct reaction of MPDNP-F with E2 at 60°C in the presence of 4-dimethylaminopyridine (DMAP). DMAP served as the organic catalyst and had a less negative effect on the LC/ESI-MS/MS instrument compared to the non-volatile inorganic salt (NaHCO3), which was used in the previous method. The collision-induced dissociation of the molecular cation ([M]+) of the resulting derivative provided a product ion containing the E2-skeleton ([M-NO2-H]+), which significantly enhanced the assay sensitivity and specificity; compared to the dansyl chloride derivatization, which is the currently most-used derivatization procedure for the LC/ESI-MS/MS assays of E2, the MPDNP-F derivatization had significantly fewer interfering peaks and a clear and flat baseline in the serum sample analysis. The MPDNP-F derivatization-LC/ESI-MS/MS method enabled the precise and accurate quantification of E2 even at a 5.0 pg/mL concentration (lower limit of quantification) with a small sample volume (100 μL of serum/plasma) and had a tolerance for the matrix effect. This method was also proven to serve as a more sensitive and specific alternative to the clinically used chemiluminescence enzyme immunoassay.

Wearable Ion Sensors for the Detection of Sweat Ions Fabricated by Heat-Transfer Printing

Wearable ion sensors for the real-time monitoring of sweat biomarkers have recently attracted increasing research attention. Here, we fabricated a novel chloride ion sensor for real-time sweat monitoring. The printed sensor was heat-transferred onto nonwoven cloth, allowing for easy attachment to various types of clothing, including simple garments. Additionally, the cloth prevents contact between the skin and the sensor and acts as a flow path. The change in the electromotive force of the chloride ion sensor was -59.5 mTV/log CCl-. In addition, the sensor showed a good linear relationship with the concentration range of chloride ions in human sweat. Moreover, the sensor displayed a Nernst response, confirming no changes in the film composition due to heat transfer. Finally, the fabricated ion sensors were applied to the skin of a human volunteer subjected to an exercise test. In addition, a wireless transmitter was combined with the sensor to wirelessly monitor ions in sweat. The sensors showed significant responses to both sweat perspiration and exercise intensity. Thus, our research demonstrates the potential of using wearable ion sensors for the real-time monitoring of sweat biomarkers, which could significantly impact the development of personalized healthcare.

Horizon Scanning in Tissue Engineering Using Citation Network Analysis

BACKGROUND

Establishing a horizon scanning method is critical for identifying technologies that require new guidelines or regulations. We studied the application of bibliographic citation network analysis to horizon scanning.

OBJECTIVE

The possibility of applying the proposed method to interdisciplinary fields was investigated with the emphasis on tissue engineering and its example, three-dimensional bio-printing.

METHODOLOGY AND RESULTS

In all, 233,968 articles on tissue engineering, regenerative medicine, biofabrication, and additive manufacturing published between January 1, 1900 and November 3, 2021 were obtained from the Web of Science Core Collection. The citation network of the articles was analyzed for confirmation that the evolution of 3D bio-printing is reflected by tracking the key articles in the field. However, the results revealed that the major articles on the clinical application of 3D bio-printed products are located in clusters other than that of 3D bio-printers. We investigated the research trends in this field by analyzing the articles published between 2019 and 2021 and detected various basic technologies constituting tissue engineering, including microfluidics and scaffolds such as electrospinning and conductive polymers. The results suggested that the research trend of technologies required for product development and future clinical applications of the product are sometimes detected independently by bibliographic citation network analysis, particularly for interdisciplinary fields.

CONCLUSION

This method can be applied to the horizon scanning of an interdisciplinary field. However, identifying basic technologies of the targeted field and following the progress of research and the integration process of each component of technology are critical.

Detecting deception using machine learning with facial expressions and pulse rate

Given the ongoing COVID-19 pandemic, remote interviews have become an increasingly popular approach in many fields. For example, a survey by the HR Research Institute (PCR Institute in Survey on hiring activities for graduates of 2021 and 2022. https://www.hrpro.co.jp/research_detail.php?r_no=273. Accessed 03 Oct 2021) shows that more than 80% of job interviews are conducted remotely, particularly in large companies. However, for some reason, an interviewee might attempt to deceive an interviewer or feel difficult to tell the truth. Although the ability of interviewers to detect deception among interviewees is significant for their company or organization, it still strongly depends on their individual experience and cannot be automated. To address this issue, in this study, we propose a machine learning approach to aid in detecting whether a person is attempting to deceive the interlocutor by associating the features of their facial expressions with those of their pulse rate. We also constructed a more realistic dataset for the task of deception detection by asking subjects not to respond artificially, but rather to improvise natural responses using a web camera and wearable device (smartwatch). The results of an experimental evaluation of the proposed approach with 10-fold cross-validation using random forests classifier show that the accuracy and the F1 value were in the range between 0.75 and 0.8 for each subject, and the highest values were 0.87 and 0.88, respectively. Through the analysis of the importance of the features the trained models, we revealed the crucial features of each subject during deception, which differed among the subjects.

Controlling Molecular Dye Encapsulation in the Hydrophobic Core of Core-Shell Nanoparticles for In Vivo Imaging

Polymeric nanoparticles with a hydrophobic core are valuable biomedical materials with potential applications in in vivo imaging and drug delivery. These materials are effective at protecting vulnerable molecules, enabling them to serve their functions in hydrophilic physiological environments; however, strategies that allow the chemical composition and molecular weight of polymers to be tuned, forming nanoparticles to control the functional molecules, are lacking. In this article, we review strategies for designing core-shell nanoparticles that enable the effective and stable encapsulation of functional molecules for biomedical applications. IR-1061, which changes its optical properties in response to the microenvironment are useful for in vitro screening of the in vivo stability of polymeric nanoparticles. An in vitro screening test can be performed by dispersing IR-1061-encapsulated polymer nanoparticles in water, saline, buffer solution, aqueous protein solution, etc., and measuring the absorption spectral changes. Through the screening, the effects of the polarity, molecular weight, and the chiral structure of polymers consisting of polymer nanoparticles on their stability have been revealed. Based on the findings presented here, more methodologies for the effective application of various biomolecules and macromolecules with complex high-dimensional structures are expected to be developed.

Analysis of Morphological Changes in the Nucleus and Vacuoles of Acanthamoeba castellanii following Giant Virus Infection

Acanthamoeba castellanii medusavirus is a member of the phylum Nucleocytoviricota, also known as giant viruses, and has a unique strategy of infecting Acanthamoeba castellanii and replicating viral genes in the host nucleus. Here, we show time series changes in the intracellular morphology, including the nucleus, of host cells infected with four types of giant viruses, including medusavirus, using time-lapse phase-contrast microscopy and image analysis. We updated our phase-contrast-based kinetic analysis algorithm for amoebae (PKA3) to use multiple microscopic images with different focus positions to allow a more detailed analysis of their intracellular structures. Image analysis using PKA3 revealed that as medusavirus infection progressed, the host nucleus increased in size and the number of vacuoles decreased. In addition, infected host cells are known to become smaller and rounder at later stages of infection, but here they were found to be larger than uninfected cells at earlier stages. These results suggested that the propagation mechanism of medusavirus includes the formation of empty virus particles in the host cytoplasm, packaging of the viral genome replicated in the host nucleus, and then the release of viral particles. IMPORTANCE In this study, we quantitatively revealed how long the increase in host cell size or the increase in host nucleus size occurs after infection with giant viruses, especially medusavirus. To understand the underlying mechanism, we performed image analysis and determined that the host cell size increased at approximately 6 h postinfection (hpi) and the host nucleus enlarged at approximately 22 hpi, pointing to the importance of biochemical experiments. In addition, we showed that the intracellular structures could be quantitatively analyzed using multiple phase-contrast microscopy images with different focus positions at the same time point. Hence, morphological analyses of intracellular structures using phase-contrast microscopy, which have wide applications in live-cell observations, may be useful in studying various organisms that infect or are symbiotic with A. castellanii.

Kinetic Analysis of Acanthamoeba castellanii Infected with Giant Viruses Quantitatively Revealed Process of Morphological and Behavioral Changes in Host Cells

Most virus-infected cells show morphological and behavioral changes, which are called cytopathic effects. Acanthamoeba castellanii, an abundant, free-living protozoan, serves as a laboratory host for some viruses of the phylum Nucleocytoviricota-the giant viruses. Many of these viruses cause cell rounding in the later stages of infection in the host cells. Here, we show the changes that lead to cell rounding in the host cells through time-lapse microscopy and image analysis. Time-lapse movies of A. castellanii cells infected with Mimivirus shirakomae, kyotovirus, medusavirus, or Pandoravirus japonicus were generated using a phase-contrast microscope. We updated our phase-contrast-based kinetic analysis algorithm for amoebae (PKA3) and used it to analyze these time-lapse movies. Image analysis revealed that the process leading to cell rounding varies among the giant viruses; for example, M. shirakomae infection did not cause changes for some time after the infection, kyotovirus infection caused an early decrease in the number of cells with typical morphologies, and medusavirus and P. japonicus infection frequently led to the formation of intercellular bridges and rotational behavior of host cells. These results suggest that in the case of giant viruses, the putative reactions of host cells against infection and the putative strategies of virus spread are diverse. IMPORTANCE Quantitative analysis of the infection process is important for a better understanding of viral infection strategies and virus-host interactions. Here, an image analysis of the phase-contrast time-lapse movies displayed quantitative differences in the process of cytopathic effects due to the four giant viruses in Acanthamoeba castellanii, which were previously unclear. It was revealed that medusavirus and Pandoravirus japonicus infection led to the formation of a significant number of elongated particles related to intercellular bridges, emphasizing the importance of research on the interaction of viruses with host cell nuclear function. Mimivirus shirakomae infection did not cause any changes in the host cells initially, so it is thought that the infected cells can actively move and spread over a wider area, emphasizing the importance of observation in a wider area and analysis of infection efficiency. These results suggest that a kinetic analysis using the phase-contrast-based kinetic analysis algorithm for amoebae (PKA3) reveals the infection strategies of each giant virus.

The brain-specific RasGEF very-KIND is required for normal dendritic growth in cerebellar granule cells and proper motor coordination

Very-KIND/Kndc1/KIAA1768 (v-KIND) is a brain-specific Ras guanine nucleotide exchange factor carrying two sets of the kinase non-catalytic C-lobe domain (KIND), and is predominantly expressed in cerebellar granule cells. Here, we report the impact of v-KIND deficiency on dendritic and synaptic growth in cerebellar granule cells in v-KIND knockout (KO) mice. Furthermore, we evaluate motor function in these animals. The gross anatomy of the cerebellum, including the cerebellar lobules, layered cerebellar cortex and densely-packed granule cell layer, in KO mice appeared normal, and was similar to wild-type (WT) mice. However, KO mice displayed an overgrowth of cerebellar granule cell dendrites, compared with WT mice, resulting in an increased number of dendrites, dendritic branches and terminals. Immunoreactivity for vGluT2 (a marker for excitatory presynapses of mossy fiber terminals) was increased in the cerebellar glomeruli of KO mice, compared with WT mice. The postsynaptic density around the terminals of mossy fibers was also increased in KO mice. Although there were no significant differences in locomotor ability between KO and WT animals in their home cages or in the open field, young adult KO mice had an increased grip strength and a tendency to exhibit better motor performance in balance-related tests compared with WT animals. Taken together, our results suggest that v-KIND is required for compact dendritic growth and proper excitatory synaptic connections in cerebellar granule cells, which are necessary for normal motor coordination and balance.

Mammalian-Specific Central Myelin Protein Opalin Is Redundant for Normal Myelination: Structural and Behavioral Assessments

Opalin, a central nervous system-specific myelin protein phylogenetically unique to mammals, has been suggested to play a role in mammalian-specific myelin. To elucidate the role of Opalin in mammalian myelin, we disrupted the Opalin gene in mice and analyzed the impacts on myelination and behavior. Opalin-knockout (Opalin^−/−) mice were born at a Mendelian ratio and had a normal body shape and weight. Interestingly, Opalin^−/− mice had no obvious abnormalities in major myelin protein compositions, expression of oligodendrocyte lineage markers, or domain organization of myelinated axons compared with WT mice (Opalin^+/+) mice. Electron microscopic observation of the optic nerves did not reveal obvious differences between Opalin^+/+ and Opalin^−/− mice in terms of fine structures of paranodal loops, transverse bands, and multi-lamellae of myelinated axons. Moreover, sensory reflex, circadian rhythm, and locomotor activity in the home cage, as well as depression-like behavior, in the Opalin^−/− mice were indistinguishable from the Opalin^+/+ mice. Nevertheless, a subtle but significant impact on exploratory activity became apparent in Opalin^−/− mice exposed to a novel environment. These results suggest that Opalin is not critical for central nervous system myelination or basic sensory and motor activities under conventional breeding conditions, although it might be required for fine-tuning of exploratory behavior.

Three-body system metaphor for the two-slit experiment and Escherichia coli lactose-glucose metabolism

We compare the contextual probabilistic structures of the seminal two-slit experiment (quantum interference experiment), the system of three interacting bodies andEscherichia colilactose-glucose metabolism. We show that they have the same non-Kolmogorov probabilistic structure resulting from multi-contextuality. There are plenty of statistical data with non-Kolmogorov features; in particular, the probabilistic behaviour of neither quantum nor biological systems can be described classically. Biological systems (even cells and proteins) are macroscopic systems and one may try to present a more detailed model of interactions in such systems that lead to quantum-like probabilistic behaviour. The system of interactions between three bodies is one of the simplest metaphoric examples for such interactions. By proceeding further in this way (by playing withn-body systems) we shall be able to find metaphoric mechanical models for complex bio-interactions, e.g. signalling between cells, leading to non-Kolmogorov probabilistic data.

Quantum Bayesianism as the basis of general theory of decision-making

We discuss the subjective probability interpretation of the quantum-like approach to decision making and more generally to cognition. Our aim is to adopt the subjective probability interpretation of quantum mechanics, quantum Bayesianism (QBism), to serve quantum-like modelling and applications of quantum probability outside of physics. We analyse the classical and quantum probabilistic schemes of probability update, learning and decision-making and emphasize the role of Jeffrey conditioning and its quantum generalizations. Classically, this type of conditioning and corresponding probability update is based on the formula of total probability-one the basic laws of classical probability theory.