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We established a process for growing highly ordered MoS2 thin films. The process consists of four steps: MoO3 thermal evaporation, first annealing, sulfurization, and second annealing. The main feature of this process is that thermally deposited MoO3 thin films are employed as a precursor for the MoS2 films. The first deposition step enabled us to achieve precise control of the resulting thickness of the MoS2 films with high uniformity. The crystalline structures, surface morphologies, and chemical states at each step were characterized by X-ray diffraction, atomic force microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. Based on these characterizations and a careful optimization of the growth conditions, we successfully produced a highly oriented MoS2 thin film with a thickness of five monolayers over an entire one-centimeter-square sapphire substrate.

Purpose: Nordic hamstring exercise (NHE) and razor hamstring curl (RHC) are usually performed to train hamstring eccentric contraction strength. However, it is unclear whether there are differences in the intensity of the two methods and the amount of loading on each muscle. Therefore, this study was conducted using peak eccentric force and each muscle surface electromyogram (s-EMG) to provide useful information to decide whether NHE or RHC should be prescribed for training and rehabilitation., Methods: s-EMG electrodes were placed in the medial gastrocnemius, lateral gastrocnemius, biceps femoris, semitendinosus, gluteus maximus, and erector spinae of the dominant leg of the fifteen healthy male university students with exercise habits. Maximum voluntary isometric contractions of 3 seconds were performed on each muscle followed by NHE and RHC in random order. The outcome variables included peak eccentric force and s-EMG of each muscle calculated by means amplitude during the NHE and RHC., Results: Peak eccentric force was significantly higher in RHC than in NHE (p = 0.001, r = 0.73). However, NHE was significantly higher in s-EMG of semitendinosus (p = 0.04, r = -0.52) than RHC. However, there were no significant differences in EMG of the medial gastrocnemius (p = 0.202, r = -0.34), lateral gastrocnemius (p = 0.496, r = 0.18), biceps femoris (p = 0.061, r = -0.48), gluteus maximus (p = 0.112, r = -0.41), erector spinae (p = 0.45, r = 0.20) between NHE and RHC., Conclusions: For NHE and RHC, the peak eccentric force exerted during the exercise was significantly higher for RHC, and the s-EMG of semitendinosus was significantly higher for NHE., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Murakami et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Childhood glaucoma is one of the major causes of blindness in children, however, its diagnosis is of great challenge. The study aimed to demonstrate and evaluate the performance of a deep-learning (DL) model for detecting childhood glaucoma based on periocular photographs. Primary gaze photographs of children diagnosed with glaucoma with appearance features (corneal opacity, corneal enlargement, and/or globe enlargement) were retrospectively collected from the database of a single referral center. DL framework with the RepVGG architecture was used to automatically recognize childhood glaucoma from photographs. The average receiver operating characteristic curve (AUC) of fivefold cross-validation was 0.91. When the fivefold result was assembled, the DL model achieved an AUC of 0.95 with a sensitivity of 0.85 and specificity of 0.94. The DL model showed comparable accuracy to the pediatric ophthalmologists and glaucoma specialists in diagnosing childhood glaucoma (0.90 vs 0.81, p = 0.22, chi-square test), outperforming the average of human examiners in the detection rate of childhood glaucoma in cases without corneal opacity (72% vs. 34%, p = 0.038, chi-square test), with a bilateral corneal enlargement (100% vs. 67%, p = 0.03), and without skin lesions (87% vs. 64%, p = 0.02). Hence, this DL model is a promising tool for diagnosing missed childhood glaucoma cases., (© 2023. The Author(s).)

The conjugation of biomolecules, such as protein, sugar, and DNA, with metal nanoparticles is an important technique for bioassay and biomaterial preparation. In this study, we aim to enzymatically immobilize a functional peptide on gold nanoparticles (AuNPs) using a single-step reaction. We used tyrosinase, a catechol oxidase, to immobilize an enzymatic peptide. We performed immobilization experiments of a fluorescent compound-linked caspase-3 substrate peptide using tyrosinase on chitosan-coated AuNPs. Peptides were effectively immobilized onto the AuNPs depending on the presence of tyrosine within the sequence, which suggests the DOPA-quinone produced from tyrosine, via tyrosinase, is connected to the chitosan amino group. Although fluorescent emission from the immobilized capase-3 substrate was quenched by AuNPs, fluorescence intensity recovery occurred due to the addition of caspase-3. Thus, we were able to easily prepare functional AuNPs that can be used for a caspase-3 activity assay. Our results indicate that the tyrosinase-mediated peptide link to chitosan-coated particles is a useful technique for preparing functionalized nanoparticles.

Recent progress in photoactive organic field-effect transistors (OFETs) is reviewed. Photoactive OFETs are divided into light-emitting (LE) and light-receiving (LR) OFETs. In the first part, LE-OFETs are reviewed from the viewpoint of the evolution of device structures. Device performances have improved in the last decade with the evolution of device structures from single-layer unipolar to multi-layer ambipolar transistors. In the second part, various kinds of LR-OFETs are featured. These are categorized according to their functionalities: phototransistors, non-volatile optical memories, and photochromism-based transistors. For both, various device configurations are introduced: thin-film based transistors for practical applications, single-crystalline transistors to investigate fundamental physics, nanowires, multi-layers, and vertical transistors based on new concepts.

Immunodetection of methicillin-resistant Staphylococcus aureus (MRSA) by conventional methods employing mammalian immunoglobulins has unknown detection limits, and often yields false-positive results because of the presence of S. aureus protein A, which binds the Fc region of mammalian IgG. In this study, a new PBP2a-specific chicken IgY antibody was developed in inbred and conventional chickens, and used for the detection of MRSA using whole cell lysate samples. Our results showed that this chicken IgY antibody minimized the side effects of protein A. Moreover, enzyme-linked immunosorbent assay and immunochromatography systems were used with a monoclonal and polyclonal anti-PBP2a IgY antibody, clearly differentiating MRSA from methicillin-sensitive S. aureus and other methicillin-sensitive Staphylococcus spp. The detection limit of the immunochromatography was 10(8) colony-forming units; therefore, 1 colony on an agar plate was adequate to distinguish MRSA from non-MRSA. The specificity and sensitivity of this assay were almost similar to that of a commercially available latex agglutination test; however, the procedure used in this study was less complicated. The entire detection procedure, including sample preparation, takes only 20 min and does not require special equipment. Therefore, the use of this IgY antibody as a new tool for the detection of MRSA is highly recommended.

Apoptosis signal-regulating kinase 1 (ASK1) is a member of the mitogen-activated protein kinase kinase kinase (MAP3K) family that activates downstream MAP kinases (MAPKs), c-Jun N-terminal kinases (JNKs) and p38 MAPKs, in response to various stresses, such as reactive oxygen species (ROS), endoplasmic reticulum (ER) stress, lipopolysaccharide, and calcium overload. Activation of the JNK and p38 pathways induces stress responses such as cell death, differentiation, and the production of inflammatory cytokines. A series of studies using ASK1-deficient mice have indicated that ASK1 plays important roles in many stress-related diseases, including cardiovascular and neurodegenerative diseases, suggesting that small compounds that inhibit ASK1 activity could possibly be used for the amelioration of the development and/or progression of these diseases. In this review, we provide an overview of the pathophysiological roles of ASK1-dependent signaling pathways and discuss the mechanistic basis for how these could serve as potential therapeutic targets.

Cells and organisms face anoxia in a wide variety of contexts, including ischemia and hibernation. Cells respond to anoxic conditions through multiple signaling pathways. We report that NSY-1, the Caenorhabditis elegans ortholog of mammalian apoptosis signal-regulating kinase (ASK) family of MAP kinase (MAPK) kinase kinases (MAP3Ks), regulates viability of animals in anoxia. Loss-of-function mutations of nsy-1 increased survival under anoxic conditions, and increased survival was also observed in animals with mutations in tir-1 and the MAPK kinase (MAP2K) sek-1, which are upstream and downstream factors of NSY-1, respectively. Consistent with these findings, anoxia was found to activate the p38 MAPK ortholog PMK-1, and this was suppressed in nsy-1 and tir-1 mutant animals. Furthermore, double-mutant analysis showed that the insulin-signaling pathway, which also regulates viability in anoxia, functioned in parallel to NSY-1. These results suggest that the TIR-1-NSY-1-SEK-1-PMK-1 pathway plays important roles in the reponse to anoxia in C. elegans., (© 2011 by the Genetics Society of America)

Grandinal, a new dimeric phloroglucinol compound, was isolated from Eucalyptus grandis and characterized by spectral techniques. Tautomeric structures 1, 2, and 3 were assigned to grandinal. Biogenetically, 1 is proposed to be formed from intermediates derived from grandinol and jensenone.

From the viewpoint of T-cell receptor (TCR) repertoire, we studied the role of T cells in acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (allo-BMT) from an HLA-identical sibling. By means of inverse polymerase chain reaction method and DNA sequencing, we analyzed TCR-alpha and -beta transcripts from GVHD lesions and peripheral blood (PB) in a patient with typical GVHD together with PB from donor. At the initial onset of GVHD, V alpha-7 and -19 subfamilies were oligoclonally expanded in the PB compared with those in the oral mucosal lesions. At the second onset, V alpha-2, and V beta-6 subfamilies were more frequently detected in the cutaneous lesion than in the PB. Some TCR transcripts were recurrently found either in the mucosal or cutaneous lesions (or in both) and not in the PB. Furthermore, some of recurrent TCR transcripts in the lesions shared V gene segments and common motifs of complementarity determining region-3. These findings suggested that T cells infiltrating the GVHD lesions recognized a limited kind of antigens presented by patient's tissues with GVHD, and that T-cell repertoire in the GVHD lesions was different from that in the PB.