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ABSTRACT: Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) has become a serious epidemiologic problem worldwide. In this study, we aimed to investigate recently isolated MRSA types and determine their characteristics. Methods: We collected 164 strains isolated from 13 hospitals located in Tokyo and surrounding prefectures. In addition to drug resistance tests, we sequenced whole genomes of the prevalent MRSA clones and analysed their genomic characteristics, such as drug resistance genes, virulence factor genes, and genome arrangements. Results: Multilocus sequencing typing showed that 51% of the SCCmecⅣ MRSA isolates belonged to clonal complex 1 (CC1). Staphylococcus protein A gene (spa) typing showed that 91% of these CC1 isolates could be categorised as t1784 type. These CC1/t1784 isolates possessed genes encoding erythromycin resistance protein, spectinomycin 9-adenylyltransferase, and staphylococcal enterotoxins (SEA, SEI, SEM), but not the pvl gene encoding Panton-Valentine leukocidin. Complete genomic analysis of nine CC1/t1784 isolates showed that they shared an intact phage, which carried no annotated virulence factor genes except for two encoding a hypothetical membrane protein and a teichoic acid biosynthesis protein. No significant genomic rearrangements were observed among the CC1/t1784 isolates. Conclusion: These data and previous reports indicate that this CC1/t1784 clone has been expanding rapidly in Japan without genomic changes.

ABSTRACT: Objectives: Proper use of antibacterial agents is necessary to prevent the spread of drug-resistant bacteria. To support clinicians, laboratories need to rapidly determine bacterial drug susceptibility/resistance. We have established a method to distinguish extended-spectrum β-lactamase (ESBL)-producing clinical isolates by capturing structural changes in β-lactam antibiotics using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS). Methods: Clinical isolates of Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis, classified into ESBL-producing strains and sensitive strains based on the presence or absence of a CTX-M-type gene, were used. Test bacteria were cultured aerobically in solid-phase wells of Eiken DPD1 dry plates at 35°C for 15 min or 30 min with the antibiotics cefotaxime (CTX), cefpodoxime (CPDX) or piperacillin (PIPC). Culture supernatants were then used for analysis with a MALDI Biotyper. Results: Signals derived from non-hydrolyzed products of antibiotics were observed in all strains. In the case of ESBL-producing strains, signals derived from the hydrolysis products of antibiotics were also observed. Since the ratio of signal intensity derived from hydrolysis products divided by the total signal intensity detected was ≥11% for CTX and ≥6% for CPDX and PIPC, all strains were determined to be ESBL-producing bacteria. Conclusion: The short incubation time of 15 min suggests that this method can identify ESBL-producing strains much more rapidly than conventional methods.

IGLL5 is shown to be located near super-enhancer (SE) in B-cell tumors, and this gene is frequently mutated and a target of translocation in B-cell tumors. These results suggest roles of the IGLL5 in tumorigenesis; however, its functional properties have been unclear. We found that two mature B-cell lymphoma cell lines expressed IGLL5 mRNA with Cλ1 segment. JQ1 treatment resulted in down-expression of IGLL5, indicating that IGLL5 is controlled by SE. IGLL5 knockdown induced cell death with down-expression of MYC. Our results suggested that IGLL5 might have a role in survival of mature B-cell tumors and involvement in MYC expression. (100 words)

Summary: While androgen is considered a pivotal regulator of sexually dimorphic development, it remains unclear how it orchestrates the differentiation of reproductive organs. Using external genitalia development as a model, we showed that androgen, through the transcription factor MafB, induced cell migration by remodeling the local extracellular matrix (ECM), leading to increased cell contractility and focal adhesion assembly. Furthermore, we identified the matrix metalloproteinase Mmp11 as a MafB target gene under androgen signaling. MMP11 remodels the local ECM environment by degrading Collagen VI (ColVI). The reduction of ColVI led to the fibrillar deposition of fibronectin in the MafB-expressing bilateral mesenchyme both in vivo and ex vivo. The ECM remodeling and development of migratory cell characteristics were lost in the MafB loss-of-function mice. These results demonstrate the requirement of mesenchymal-derived androgen signaling on ECM-dependent cell migration, providing insights into the regulatory cellular mechanisms underlying androgen-driven sexual differentiation.

Wound healing is an important process in various diseases, and elucidating the underlying mechanism is essential for developing therapeutic strategies. We investigated whether the loss of transient receptor potential ankyrin 1 (TRPA1) affects the cutaneous wound healing process in mice. We assessed the formation of granulation tissue by myofibroblasts and macrophages, re-epithelialization, and related gene expression. TRPA1-null (KO) and wild-type (WT) C57BL/6 mice were used for establishing the wound model. Two round full-thickness excision wounds (diameter, 5.0 mm) were produced in the dorsal skin of mice under general anesthesia. After specific intervals, healing was evaluated using macroscopic observation, histology, immunohistochemistry, and real-time reverse transcription-polymerase chain reaction (RT-PCR). TRPA1 KO retarded the formation of granulation tissue and re-epithelialization in the healing of cutaneous wound. Furthermore, TRPA1 KO suppressed the appearance of myofibroblasts, macrophage infiltration, and mRNA expression of αSMA, F4/80, and Col-1α2. These findings indicate that TRPA1 is required for cutaneous wound healing in mice. The lack of TRPA1 retards macrophage infiltration and the subsequent fibrotic tissue formation, which might further impair the fibrogenic behavior of fibroblasts.

To accommodate highly-mixed variable-volume assembly production, a human-robot cooperative production line utilizing a robotic cell is promising. A robotic cell is equipped with an industrial robot of which motion plans can be switched depending on the product variation. The motion plans should be switched quickly as possible on the demand from market, but the planning is one of the time-consuming tasks. This study aims to develop an automatic planning method for assembly motion using the geometric constraint conditions on 3D CAD data of the products. It was found that reduction of planning work-time by 61% can be achieved compared with the manual planning method.

Glutamate excitotoxicity mediated by N-methyl-d-aspartate (NMDA) receptors is an important cause of retinal ganglion cell death in glaucoma. To elucidate whether apelin protects against retinal neuronal cell death, we examined protective effects of exogenous and endogenous apelin on neuronal cell death induced by intravitreal injection of NMDA in the retinas of mice. An intravitreal injection of NMDA induced neuronal cell death in both the retinal ganglion cell layer and inner nuclear layer, and reduced the amplitudes of scotopic threshold response (STR) in electroretinography studies. Both cell death and STR amplitudes decrease induced by NMDA were prevented by a co-injection of [Pyr1]-apelin-13, and were facilitated by apelin deficiency. The neuroprotective effects of [Pyr1]-apelin-13 were blocked by an apelin receptor APJ antagonist, and by inhibitors of Akt and extracellular signal-regulated kinase 1/2 signaling pathways. Additionally, an intravitreal injection of tumor necrosis factor-α (TNF-α) neutralizing antibody prevented NMDA-induced retinal neuronal cell death, and exogenous and endogenous apelin suppressed NMDA-induced upregulation of TNF-α in the retina. These results suggest that apelin protects neuronal cells against NMDA-induced death via an APJ receptor in the retina, and that apelin may have beneficial effects in the treatment of glaucoma.