Monoclonal antibody Y01 prevents tauopathy progression induced by lysine 280-acetylated tau in cell and mouse models.

The spatiotemporal pattern of the spread of pathologically modified tau through brain regions in Alzheimer's disease (AD) can be explained by prion-like cell-to-cell seeding and propagation of misfolded tau aggregates. Hence, to develop targeted therapeutic antibodies, it is important to identify the seeding- and propagation-competent tau species. The hexapeptide 275VQIINK280 of tau is a critical region for tau aggregation, and K280 is acetylated in various tauopathies, including AD. However, the mechanism that links tau acetylated on lysine 280 (tau-acK280) to subsequent progression to neurodegenerative disease remains unclear. Here, we demonstrate that tau-acK280 is critical for tau propagation processes including secretion, aggregation, and seeding. We developed an antibody, Y01, that specifically targets tau-acK280 and solved the crystal structure of Y01 in complex with an acK280 peptide. The structure confirmed that Y01 directly recognizes acK280 and the surrounding residues. Strikingly, upon interaction with acetylated tau aggregates, Y01 prevented tauopathy progression and increased neuronal viability in neuron cultures and in tau-Tg mice through antibody-mediated neutralization and phagocytosis, respectively. Based on our observations that tau-acK280 is a core species involved in seeding and propagation activities, the Y01 antibody that specifically recognizes acK280 represents a promising therapeutic candidate for AD and other neurodegenerative diseases associated with tauopathy.

Structure-based molecular characterization of the YetL transcription factor from Bacillus subtilis.

Bacillus subtilis is a gram-positive bacterium that has developed to coordinate gene expression and to survive against changes of nutrients and toxic chemicals. Flavonoids are exuded by plant cells and are abundant in the soil. To counteract the antibacterial effects of flavonoids, B. subtilis expresses flavonoid-detoxifying enzymes, and their expression is negatively regulated by transcription factors, including YetL. YetL was shown to control B. subtilis growth through the promoter regions of yetL and yetM genes in response to some flavonoids. Despite the functional significance of the YetL transcription factor in bacterial survival, no structural information is available for YetL. Here, we report the crystal structure of YetL and propose a flavonoid-induced regulatory mechanism. The YetL structure contains the canonical winged helix-turn-helix motif of the MarR superfamily but distinctly presents an additional N-terminal helix. In the dimeric assembly of YetL, the H1 helix intersects the YetL dimer and contributes to extensive intersubunit interactions. As a transcription factor, YetL recognizes a 28-mer operator of double-stranded DNA that contains a palindromic sequence. Moreover, our comparative structural analysis of YetL and other MarR members allows us to propose a flavonoid-induced transcription regulatory mechanism that is used for bacterial adaptation to environmental changes and stresses.

Would You Trust Driverless Service? Formation of Pedestrian's Trust and Attitude Using Non-Verbal Social Cues.

Despite the widespread application of Autonomous Vehicles (AV) to various services, there has been relatively little research carried out on pedestrian-AV interaction and trust within the context of service provided by AV. This study explores the communication design strategy promoting a pedestrian's trust and positive attitude to driverless services within the context of pedestrian-AV interaction using non-verbal social cues. An empirical study was conducted with an experimental VR environment to measure participants' intimacy, trust, and brand attitude toward AV. Further understanding of their social interaction experiences was explored through semi-structured interviews. As a result of the study, the interaction effect of social cues was found, and it was revealed that brand attitude was formed by the direct effects of intimacy and trust as well as the indirect effects of intimacy through trust's mediation. Furthermore, 'Conceptual Definition of Space' was identified to generate differences in the interplay among intimacy, trust, and brand attitude according to social cues. Quantitative and qualitative results were synthesized to discuss implications considering the service context. Practical implications were also addressed suggesting specific design strategies for utilizing the sociality of AV.

Structure-based molecular characterization of the LltR transcription factor from Listeria monocytogenes.

Listeria monocytogenes is a psychrotrophic food-borne pathogenic bacterium that causes listeriosis. Due to its unusual adaptation, an ability to grow at extended temperatures ranging from 4 to 45 °C, L. monocytogenes is notoriously hard to control in food-manufacturing processes. In addition, the growing number of antibiotic-resistant L. monocytogenes strains have made listeriosis steadily refractory to clinical treatments and can lead to serious life-threatening diseases, such as sepsis and meningitis, in immunocompromised persons and neonates. Transcription factors that belong to the PadR family play a key role in bacterial survival against unfavorable environmental stresses. The LltR protein from L. monocytogenes was identified as a PadR-type transcription factor and was shown to be required for bacterial growth adaptation at low temperatures. Despite the functional significance of LltR in listeria survival and pathogenesis, our molecular understanding of the LltR-mediated transcriptional regulation is highly limited. Here, we report the crystal structure of LltR and reveal the operator DNA recognition mechanism used by LltR. LltR dimerizes into an isosceles triangle-like shape and requires a winged helix-turn-helix motif for dsDNA recognition. Indeed, LltR and putative operator dsDNA binding was observed and suggests a transcriptional repression of the llfR-lmo0600-lmo0601 operon by direct interaction between the LltR transcription factor and its promoter region. Structure-based comparative and mutational analyses showed that LltR interacts with dsDNA via a unique strategy that combines both LltR-specific and PadR family-common mechanisms.

Altered Gut Microbiota in Korean Children with Autism Spectrum Disorders.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and behavioral impairments. Recent studies have suggested that gut microbiota play a critical role in ASD pathogenesis. Herein, we investigated the fecal microflora of Korean ASD children to determine gut microbiota profiles associated with ASD. Specifically, fecal samples were obtained from 54 children with ASD and 38 age-matched children exhibiting typical development. Systematic bioinformatic analysis revealed that the composition of gut microbiota differed between ASD and typically developing children (TDC). Moreover, the total amounts of short-chain fatty acids, metabolites produced by bacteria, were increased in ASD children. At the phylum level, we found a significant decrease in the relative Bacteroidetes abundance of the ASD group, whereas Actinobacteria abundance was significantly increased. Furthermore, we found significantly lower Bacteroides levels and higher Bifidobacterium levels in the ASD group than in the TDC group at the genus level. Functional analysis of the microbiota in ASD children predicted that several pathways, including genetic information processing and amino acid metabolism, can be associated with ASD pathogenesis. Although more research is needed to determine whether the differences between ASD and TDC are actually related to ASD pathogenesis, these results provide further evidence of altered gut microbiota in children with ASD, possibly providing new perspectives on the diagnosis and therapeutic approaches for ASD patients.

Effects of ID-HWS1000 on the Perception of Bowel Activity and Microbiome in Subjects with Functional Constipation: A Randomized, Double-Blind Placebo-Controlled Study.

During constipation, indigestible foods, such as probiotics, prebiotics, and dietary fiber, may improve the bowel environment and activity. In this randomized, double-blind, and placebo-controlled study, the effects of ID-HWS1000, composed of Lactobacillus and Bifidobacterium species, xylooligosaccharide, and dietary fiber, were evaluated to determine whether it improves the perception of bowel activity or cause changes in the gut microbiome. Thirty Korean adults with "functional constipation" according to the Rome III criteria were randomly assigned to the following groups: 20 in the ID-HWS1000 group and 10 in the placebo group. ID-HWS1000 or the placebo was consumed by the participants for 4 weeks. To assess the changes in the perception of bowel activity, clinical data and gut microbiome analyses were conducted before and after the experiment. There were significant differences between the groups in the response to 9 of the 12 survey questions (the number and duration of bowel movements, amount of feces, number of irritant bowel movements, number of times bowel movements felt incomplete, shape of the feces, amount of gas in the gut, discomfort after defecation, and discomfort owing to constipation) (P < .05). There was a decrease in the proportion of Firmicutes (Ruminococcaceae and Lachnospiraceae) and an increase in Bacteroidetes (Bacteroidaceae) (P < .05). Moreover, ID-HWS1000 directly improved the discomfort associated with bowel movements, decreased the proportion of Lachnospiraceae, and increased the proportion of Bacteroidaceae. These results confirmed that ID-HWS1000 improves the perception of bowel activity and exerts positive changes in individuals with functional constipation.

Structure-based functional analysis of a PadR transcription factor from Streptococcus pneumoniae and characteristic features in the PadR subfamily-2.

Since the first discovery of phenolic acid decarboxylase transcriptional regulator (PadR), its homologs have been identified mostly in bacterial species and constitute the PadR family. PadR family members commonly contain a winged helix-turn-helix (wHTH) motif and function as a transcription factor. However, the PadR family members are varied in terms of molecular size and structure. As a result, they are divided into PadR subfamily-1 and PadR subfamily-2. PadR subfamily-2 proteins have been reported in some pathogenic bacteria, including Listeria monocytogenes and Streptococcus pneumoniae, and implicated in drug resistance processes. Despite the growing numbers of known PadR family proteins and their critical functions in bacteria survival, biochemical and biophysical studies of the PadR subfamily-2 are limited. Here, we report the crystal structure of a PadR subfamily-2 member from Streptococcus pneumoniae (SpPadR) at a 2.40 Å resolution. SpPadR forms a dimer using its N-terminal and C-terminal helices. The two wHTH motifs of a SpPadR dimer expose their positively charged residues presumably to interact with DNA. Our structure-based mutational and biochemical study indicates that SpPadR specifically recognizes a palindromic nucleotide sequence upstream of its encoding region as a transcriptional regulator. Furthermore, comparative structural analysis of diverse PadR family members combined with a modeling study highlights the structural and regulatory features of SpPadR that are canonical to the PadR family or specific to the PadR subfamily-2.

Effect of playing soccer on stress, sociality, and physical fitness in alienated youth: a retrospective study.

This study was to analyze bullying experiences, physical fitness, and stress and social support in young students who have taken part in a soccer program for approximately 3 years. Fifty-two participants who were divided into two groups: a control group that had not experienced alienation (NAG; n=45, 86.5%) and an experimental group that had ex-perienced alienation (AG; n=7, 13.5%). The frequency of alienation in AG was '1-2 times' or 'a few times' per week. NAG believed their in-volvement in the soccer program helped them improve their relation-ships with friends, cope with alienation, and overcome bullying. Muscle mass and basal metabolic rate of NAG showed higher levels than those of AG. Strength of NAG was significantly higher than that of AG. Stress levels of NAG were significantly lower than those of AG. Although so-cial support was not significantly different between groups, there was a higher tendency in NAG to have stronger social support compared to AG. In conclusion, this study suggests that physical fitness and stress levels can be improved by playing soccer. In particular, participating in a soccer program for an extended period of time can benefit individuals who are socially alienated.

Selective thiolation and photoswitching mechanism of Cy5 studied by time-dependent density functional theory.

Cy5 is one of the most widely used organic dyes with a photoswitching property. It can be reversibly photoconverted to the dark state through thiolation with primary thiols. Although photoswitching of Cy5 has been widely used in super-resolution nanoscopy, its thiolation mechanism remains unclear. We carried out time-dependent density functional theory calculations to investigate the excited state dynamics of Cy5 and observed its site-selective thiolation on both the ground and excited states. Scanning the excited state potential energy surfaces by rotating individual C-C bonds revealed structural similarity between the twisted form of Cy5 and the Cy5 subunit in the thiolated Cy5, which suggests that the dark state formation is strongly associated with the torsional motion on the excited state.

Crystal structure of the Pseudomonas aeruginosa PA0423 protein and its functional implication in antibiotic sequestration.

Pseudomonas aeruginosa is a widely found opportunistic pathogen. The emergence of multidrug-resistant strains and persistent chronic infections have increased. The protein encoded by the pa0423 gene in P. aeruginosa is proposed to be critical for pathogenesis and could be a virulence-promoting protease or a bacterial lipocalin that binds a lipid-like antibiotic for drug resistance. Although two functions of proteolysis and antibiotic resistance are mutually related to bacterial survival in the host, it is very unusual for a single-domain protein to target unrelated ligand molecules such as protein substrates and lipid-like antibiotics. To clearly address the biological role of the PA0423 protein, we performed structural and biochemical studies. We found that PA0423 adopts a single-domain ß-barrel structure and belongs to the lipocalin family. The PA0423 structure houses an internal tubular cavity, which accommodates a ubiquinone-8 molecule. Furthermore, we reveal that PA0423 can directly interact with the polymyxin B antibiotic using the internal cavity, suggesting that PA0423 has a physiological function in the antibiotic resistance of P. aeruginosa.

Structure-based molecular characterization and regulatory mechanism of the LftR transcription factor from Listeria monocytogenes: Conformational flexibilities and a ligand-induced regulatory mechanism.

Listeria monocytogenes is a foodborne pathogen that causes listeriosis and can lead to serious clinical problems, such as sepsis and meningitis, in immunocompromised patients and neonates. Due to a growing number of antibiotic-resistant L. monocytogenes strains, listeriosis can steadily become refractory to antibiotic treatment. To develop novel therapeutics against listeriosis, the drug resistance mechanism of L. monocytogenes needs to be determined. The transcription factor LftR from L. monocytogenes regulates the expression of a putative multidrug resistance transporter, LieAB, and belongs to the PadR-2 subfamily of the PadR family. Despite the functional significance of LftR, our molecular understanding of the transcriptional regulatory mechanism for LftR and even for the PadR-2 subfamily is highly limited. Here, we report the crystal structure of LftR, which forms a dimer and protrudes two winged helix-turn-helix motifs for DNA recognition. Structure-based mutational and comparative analyses showed that LftR interacts with operator DNA through a LftR-specific mode as well as a common mechanism used by the PadR family. Moreover, the LftR dimer harbors one intersubunit cavity in the center of the dimeric structure as a putative ligand-binding site. Finally, conformational flexibilities in the LftR dimer and in the cavity suggest that a ligand-induced regulatory mechanism would be used by the LftR transcription factor.

Effects of Individuality, Education, and Image on Visual Attention: Analyzing Eye-tracking Data using Machine Learning.

Machine learning, particularly classification algorithms, constructs mathematical models from labeled data that can predict labels for new data. Using its capability to identify distinguishing patterns among multi-dimensional data, we investigated the impact of three factors on the observation of architectural scenes: individuality, education, and image stimuli. An analysis of the eye-tracking data revealed that (1) a velocity histogram was unique to individuals, (2) students of architecture and other disciplines could be distinguished via endogenous parameters, but (3) they were more distinct in terms of seeking structural versus symbolic elements. Because of the reverse nature of the classification algorithms that automatically learn from data, we could identify relevant parameters and distinguishing eye-tracking patterns that have not been reported in previous studies.

Crystal structure of Bacillus cereus flagellin and structure-guided fusion-protein designs.

Flagellin is a major component of the flagellar filament. Flagellin also functions as a specific ligand that stimulates innate immunity through direct interaction with Toll-like receptor 5 (TLR5) in the host. Because flagellin activates the immune response, it has been of interest to develop as a vaccine adjuvant in subunit vaccines or antigen fusion vaccines. Despite the widespread application of flagellin fusion in preventing infectious diseases, flagellin-antigen fusion designs have never been biophysically and structurally characterized. Moreover, flagellin from Salmonella species has been used extensively despite containing hypervariable regions not required for TLR5 that can cause an unexpected immune response. In this study, flagellin from Bacillus cereus (BcFlg) was identified as the smallest flagellin molecule containing only the conserved TLR5-activating D0 and D1 domains. The crystal structure of BcFlg was determined to provide a scheme for fusion designs. Through homology-based modeling and comparative structural analyses, diverse fusion strategies were proposed. Moreover, cellular and biophysical analysis of an array of fusion constructs indicated that insertion fusion at BcFlg residues 178-180 does not interfere with the protein stability or TLR5-stimulating capacity of flagellin, suggesting its usefulness in the development and optimization of flagellin fusion vaccines.

Regular physical education class enhances sociality and physical fitness while reducing psychological problems in children of multicultural families.

This study investigated the influence of physical education class (PEC) as an intervention method for aggression, sociality, stress, and physical fitness levels in children from multicultural families. The hypothesis was that participating in PEC would result in reduced aggression and stress and improved sociality and physical fitness in multicultural children. A three-item questionnaire, a body composition test, and physical fitness tests were given three times. Eighty-four subjects were divided into four groups: multicultural children who participated in PEC (multi-PEG, n=12), multicultural children who did not participate in PEC (multi-NPEG, n=13), single-cultural children who participated in PEC (sing-PEG, n=11), and single-cultural children who did not participate in PEC (sing-NPEG, n=12), respectively. Parametric and nonparametric statistical methods were conducted on the collected data with a significance level set a priori at P<0.05. After 8 weeks of PEC, fat mass (F=2.966, P=0.045) and body mass index (F=3.654, P=0.021) had significantly different interaction effects. In the aspect of interaction effects from physical fitness variables, cardiopulmonary endurance (F=21.961, P=0.001), flexibility (F=8.892, P=0.001), muscular endurance (F=31.996, P=0.001), muscular strength (F=4.570, P=0.008), and power (F=24.479, P=0.001) were significantly improved in the multi-PEG compared to those of the other three groups. Moreover, sociality (F=22.144, P=0.001) in the multi-PEG was enhanced, whereas aggression (F=6.745, P=0.001) and stress (F=3.242, P=0.033) levels were reduced. As conclusion, the PEC reduced aggression and stress levels, and improved sociality and physical fitness levels after 8 weeks. This study confirmed that PEC for children from multicultural families can improve psychosocial factors and physical health.

Relationship between cardiopulmonary responses and isokinetic moments: the optimal angular velocity for muscular endurance.

Most protocols for testing and rehabilitation for recovery and improvement of muscular endurance have been set at 180°/sec, 240°/sec, and 300°/sec. These protocols can cause confusion to clinical providers or other researchers. This study was aimed at investigating the optimal isokinetic angular speed for measuring or developing muscular endurance after assessing the relationship between cardiopulmonary responses and isokinetic moments. This study was conducted with 31 male and female college students. Graded exercise test and body composition were measured as well as the isokinetic moments of the knee muscles at three angular speeds: 180°/sec, 240°/sec, and 300°/sec. The specific isokinetic moments of knee muscles that were measured included: peak torque (PT) and total work (TW) on extensor (e) and flexor (f) of knee joints, which were denoted as ePT180, fPT180, eTW180, fTW180, ePT240, fPT240, eTW240, fTW240, ePT300, fPT300, eTW300, and fTW300 according to the three angular speeds. Spearman correlation test was used to examine the relationship between the sum means of cardiopulmonary responses and the variables of isokinetic moments. This study confirmed that the optimal angular speed for testing or training for muscular endurance was 180°/sec, which showed a stronger relationship between cardiopulmonary responses and isokinetic moments. Therefore, this angular speed is recommended for testing and training for muscular endurance of the knee joints.

Crystal structure of the flagellar chaperone FliS from Bacillus cereus and an invariant proline critical for FliS dimerization and flagellin recognition.

FliS is a cytoplasmic flagellar chaperone for the flagellin, which polymerizes into filaments outside of the flagellated bacteria. Cytoplasmic interaction between FliS and flagellin is critical to retain the flagellin protein in a monomeric form, which is transported from the cytoplasm through the flagellar export apparatus to the extracellular space for filament assembly. Defects in the FliS protein directly diminish bacterial motility, pathogenicity, and viability. Although the overall structure of FliS is known, structural and mutational studies on FliS from other bacterial species are still required to reveal any unresolved biophysical features of FliS itself or functionally critical residues for flagellin recognition. Here, we present the crystal structure of FliS from Bacillus cereus (BcFliS) at 2.0 Å resolution. FliS possesses a highly dynamic N-terminal region, which is appended to the common four-helix bundle structure. An invariant proline residue (Pro17 in B. cereus FliS) was identified in all known FliS sequences between the N-terminal region and the four-helix bundle. The N-terminal proline residue functions as a helix breaker critical for FliS dimerization and flagellin recognition.

Electrochemical Li Topotactic Reaction in Layered SnP3 for Superior Li-Ion Batteries.

The development of new anode materials having high electrochemical performances and interesting reaction mechanisms is highly required to satisfy the need for long-lasting mobile electronic devices and electric vehicles. Here, we report a layer crystalline structured SnP3 and its unique electrochemical behaviors with Li. The SnP3 was simply synthesized through modification of Sn crystallography by combination with P and its potential as an anode material for LIBs was investigated. During Li insertion reaction, the SnP3 anode showed an interesting two-step electrochemical reaction mechanism comprised of a topotactic transition (0.7-2.0 V) and a conversion (0.0-2.0 V) reaction. When the SnP3-based composite electrode was tested within the topotactic reaction region (0.7-2.0 V) between SnP3 and LixSnP3 (x ≤ 4), it showed excellent electrochemical properties, such as a high volumetric capacity (1st discharge/charge capacity was 840/663 mA h cm-3) with a high initial coulombic efficiency, stable cycle behavior (636 mA h cm-3 over 100 cycles), and fast rate capability (550 mA h cm-3 at 3C). This layered SnP3 anode will be applicable to a new anode material for rechargeable LIBs.

Analysis of ipsilateral and bilateral ratios in male amateur golfers.

The number of injuries that force golfers to quit is also increasing. In particular, the upper body injuries are concerns for amateur golfers. This study was conducted not only to investigate muscular balance, such as ipsilateral and bilateral ratios of the upper body, but to also evaluate the possible problems of muscular joints in amateur golfers. Male golfers (n=10) and a healthy control group (n=10) were recruited for the assessment of muscular function in the upper body, which was measured by an isokinetic dynamometer at 60°/sec. The tested parts were trunk, wrist, forearm, elbow, and shoulder joints. Mann-Whitney U-test was used to evaluate the significance of the differences between groups. The ipsilateral ratios of peak torque or work per repetition (WR) of trunk flexor and extensor in the golfers were not significantly different compared to those of the control group. These results were similar to the shoulder horizontal abductor and adductor. However, there were significant differences in the ipsilateral and bilateral ratios of the wrist, forearm, and elbow joints. Especially, the WR of the wrist flexor, forearm pronator, and elbow flexor on the left side of amateur golfers showed imbalances in bilateral ratios. Moreover, the WR of the wrist and elbow flexors on the left side of amateur golfers were lower than those of the wrist and elbow extensors. Therefore, amateur golfers should strive to prevent injuries of the wrist, forearm, and elbow joints and to reinforce the endurance on those parts of the left side.

RESOLFT nanoscopy with photoswitchable organic fluorophores.

Far-field optical nanoscopy has been widely used to image small objects with sub-diffraction-limit spatial resolution. Particularly, reversible saturable optical fluorescence transition (RESOLFT) nanoscopy with photoswitchable fluorescent proteins is a powerful method for super-resolution imaging of living cells with low light intensity. Here we demonstrate for the first time the implementation of RESOLFT nanoscopy for a biological system using organic fluorophores, which are smaller in size and easier to be chemically modified. With a covalently-linked dye pair of Cy3 and Alexa647 to label subcellular structures in fixed cells and by optimizing the imaging buffer and optical parameters, our RESOLFT nanoscopy achieved a spatial resolution of ~74 nm in the focal plane. This method provides a powerful alternative for low light intensity RESOLFT nanoscopy, which enables biological imaging with small organic probes at nanoscale resolution.