Search

Periodontal diseases are among the most common infections of humans and are also associated with systemic inflammatory conditions. Colonization and pathogenicity of P. gingivalis are regulated by signal transduction pathways based on protein tyrosine phosphorylation and dephosphorylation. Here, we identify and characterize a novel component of the tyrosine (de)phosphorylation axis: a polymerase and histindinol phosphatase (PHP) family enzyme. This tyrosine phosphatase, designated Php1, was required for P. gingivalis community development with other oral bacteria, and in the absence of Php1 activity P. gingivalis was unable to cause disease in a mouse model of periodontitis. This work provides significant insights into the protein tyrosine (de)phosphorylation network in P. gingivalis, its adaptation to heterotypic communities, and its contribution to colonization and virulence., Protein-tyrosine phosphorylation in bacteria plays a significant role in multiple cellular functions, including those related to community development and virulence. Metal-dependent protein tyrosine phosphatases that belong to the polymerase and histindinol phosphatase (PHP) family are widespread in Gram-positive bacteria. Here, we show that Porphyromonas gingivalis, a Gram-negative periodontal pathogen, expresses a PHP protein, Php1, with divalent metal ion-dependent tyrosine phosphatase activity. Php1 tyrosine phosphatase activity was attenuated by mutation of conserved histidine residues that are important for the coordination of metal ions and by mutation of a conserved arginine residue, a key residue for catalysis in other bacterial PHPs. The php1 gene is located immediately downstream of the gene encoding the bacterial tyrosine (BY) kinase Ptk1, which was a substrate for Php1 in vitro. Php1 rapidly caused the conversion of Ptk1 to a state of low tyrosine phosphorylation in the absence of discernible intermediate phosphoforms. Active Php1 was required for P. gingivalis exopolysaccharide production and for community development with the antecedent oral biofilm constituent Streptococcus gordonii under nutrient-depleted conditions. In contrast, the absence of Php1 had no effect on the ability of P. gingivalis to form monospecies biofilms. In vitro, Php1 enzymatic activity was resistant to the effects of the streptococcal secreted metabolites pABA and H2O2, which inhibited Ltp1, an enzyme in the low-molecular-weight (LMW) phosphotyrosine phosphatase family. Ptk1 reciprocally phosphorylated Php1 on tyrosine residues 159 and 161, which independently impacted phosphatase activity. Loss of Php1 rendered P. gingivalis nonvirulent in an animal model of periodontal disease. Collectively, these results demonstrate that P. gingivalis possesses active PHP and LMW tyrosine phosphatases, a unique configuration in Gram-negatives which may allow P. gingivalis to maintain phosphorylation/dephosphorylation homeostasis in multispecies communities. Moreover, Php1 contributes to the pathogenic potential of the organism.

The polymicrobial microbiome of the oral cavity is a direct precursor of periodontal diseases, and changes in microhabitat or shifts in microbial composition may also be linked to oral squamous cell carcinoma. Dysbiotic oral epithelial responses provoked by individual organisms, and which underlie these diseases, are widely studied. However, organisms may influence community partner species through manipulation of epithelial cell responses, an aspect of the host microbiome interaction that is poorly understood. We report here that Porphyromonas gingivalis , a keystone periodontal pathogen, can up-regulate expression of ZEB2, a transcription factor which controls epithelial–mesenchymal transition and inflammatory responses. ZEB2 regulation by P. gingivalis was mediated through pathways involving β-catenin and FOXO1. Among the community partners of P. gingivalis , Streptococcus gordonii was capable of antagonizing ZEB2 expression. Mechanistically, S. gordonii suppressed FOXO1 by activating the TAK1-NLK negative regulatory pathway, even in the presence of P. gingivalis . Collectively, these results establish S. gordonii as homeostatic commensal, capable of mitigating the activity of a more pathogenic organism through modulation of host signaling.

Toxoplasma gondii infection results in co-option and subversion of host cellular signaling pathways. This process involves discharge of T. gondii effector molecules from parasite secretory organelles such as rhoptries and dense granules. We report that the T. gondii polymorphic dense granule protein GRA6 regulates activation of the host transcription factor nuclear factor of activated T cells 4 (NFAT4). GRA6 overexpression robustly and selectively activated NFAT4 via calcium modulating ligand (CAMLG). Infection with wild-type (WT) but not GRA6-deficient parasites induced NFAT4 activation. Moreover, GRA6-deficient parasites failed to exhibit full virulence in local infection, and the treatment of WT mice with an NFAT inhibitor mitigated virulence of WT parasites. Notably, NFAT4-deficient mice displayed prolonged survival, decreased recruitment of CD11b+ Ly6G+ cells to the site of infection, and impaired expression of chemokines such as Cxcl2 and Ccl2. In addition, infection with type I parasites culminated in significantly higher NFAT4 activation than type II parasites due to a polymorphism in the C terminus of GRA6. Collectively, our data suggest that GRA6-dependent NFAT4 activation is required for T. gondii manipulation of host immune responses to maximize the parasite virulence in a strain-dependent manner.

A conceptual design study of Japan sodium-cooled fast reactor (JSFR) is in progress as the “Fast Reactor Cycle Technology Development (FaCT)” project in Japan. A selector-valve type failed fuel detection and location (FFDL) system is applied to the JSFR design that has an upper internal structure (UIS) with a slit above the core and several sampling nozzles for the FFDL are set in the UIS around the slit to detect the fission product (FP) from the subassemblies below the slit. Therefore, mixing process in the UIS of complicated geometry should be known and appropriate arrangement of the sampling nozzles in the UIS is needed. A water experiment using a 1/5-scale model was carried out to investigate the mixing process in the UIS and concentration distribution of FP simulant. Experimental results showed that the sampling nozzles set in the UIS detected the FP simulant concentration within the criteria of FFDL signal detection, even in case of failed subassemblies under the UIS slit. In addition, identificati...

IFN-γ orchestrates cell-autonomous host defense against various intracellular vacuolar pathogens. IFN-γ-inducible GTPases, such as p47 immunity-related GTPases (IRGs) and p65 guanylate-binding proteins (GBPs), are recruited to pathogen-containing vacuoles, which is important for disruption of the vacuoles, culminating in the cell-autonomous clearance. Although the positive regulation for the proper recruitment of IRGs and GBPs to the vacuoles has been elucidated, the suppressive mechanism is unclear. Here, we show that Rab GDP dissociation inhibitor α (RabGDIα), originally identified as a Rab small GTPase inhibitor, is a negative regulator of IFN-γ-inducible GTPases in cell-autonomous immunity to the intracellular pathogen Toxoplasma gondii. Overexpression of RabGDIα, but not of RabGDIβ, impaired IFN-γ-dependent reduction of T. gondii numbers. Conversely, RabGDIα deletion in macrophages and fibroblasts enhanced the IFN-γ-induced clearance of T. gondii. Furthermore, upon a high dose of infection by T. gondii, RabGDIα-deficient mice exhibited a decreased parasite burden in the brain and increased resistance in the chronic phase than did control mice. Among members of IRGs and GBPs important for the parasite clearance, Irga6 and Gbp2 alone were more frequently recruited to T. gondii-forming parasitophorous vacuoles in RabGDIα-deficient cells. Notably, Gbp2 positively controlled Irga6 recruitment that was inhibited by direct and specific interactions of RabGDIα with Gbp2 through the lipid-binding pocket. Taken together, our results suggest that RabGDIα inhibits host defense against T. gondii by negatively regulating the Gbp2-Irga6 axis of IFN-γ-dependent cell-autonomous immunity.

IFN-γ mediates cellular innate immunity against an intracellular parasite, Toxoplasma gondii, by inducing immunity-related GTPases such as p47 IFN-γ–regulated GTPases (IRGs) and p65 guanylate-binding proteins (GBPs), which also participate in antibacterial responses via autophagy. An essential autophagy protein, Atg5, was previously shown to play a critical role in anti–T. gondii cell-autonomous immunity. However, the involvement of other autophagy proteins remains unknown. In this study, we show that essential autophagy proteins differentially participate in anti–T. gondii cellular immunity by recruiting IFN-γ–inducible GTPases. IFN-γ–induced suppression of T. gondii proliferation and recruitment of an IRG Irgb6 and GBPs are profoundly impaired in Atg7- or Atg16L1-deficient cells. In contrast, cells lacking other essential autophagy proteins, Atg9a and Atg14, are capable of mediating the anti–T. gondii response and recruiting Irgb6 and GBPs to the parasites. Although IFN-γ also stimulates anti–T. gondii cellular immunity in humans, whether this response requires GBPs and human autophagy proteins remains to be seen. To analyze the role of human ATG16L1 and GBPs in IFN-γ–mediated anti–T. gondii responses, human cells lacking ATG16L1 or GBPs were generated by the Cas9/CRISPR genome-editing technique. Although both ATG16L1 and GBPs are dispensable for IFN-γ–induced inhibition of T. gondii proliferation in the human cells, human ATG16L1 is also required for the recruitment of GBPs. Taken together, human ATG16L1 and mouse autophagy components Atg7 and Atg16L1, but not Atg9a and Atg14, participate in the IFN-γ–induced recruitment of the immunity-related GTPases to the intracellular pathogen.

Although the pyrazolone derivative sulpyrine is widely used as an antipyretic analgesic drug, side effects, including fatal shock, have been reported. However, the molecular mechanism underlying such a severe side effect is largely unclear. Here, we report that the transcription factor CREBH that is highly expressed in the liver plays an important role in fatal shock induced by sulpyrine in mice. CREBH-deficient mice were resistant to experimental fatal sulpyrine shock. We found that sulpyrine-induced expression of cytochrome P450 2B (CYP2B) family genes, which are involved in sulpyrine metabolism, in the liver was severely impaired in CREBH-deficient mice. Moreover, introduction of CYP2B in CREBH-deficient liver restored susceptibility to sulpyrine. Furthermore, ectopic expression of CREBH up-regulated CYP2B10 promoter activity, and in vivo knockdown of CREBH in wild-type mice conferred a significant resistance to fatal sulpyrine shock. These data demonstrate that CREBH is a positive regulator of CYP2B in response to sulpyrine administration, which possibly results in fatal shock.

Interferon-γ (IFN-γ) is essential for host defense against intracellular pathogens. Stimulation of innate immune cells by IFN-γ upregulates ∼2,000 effector genes such as immunity-related GTPases including p65 guanylate-binding protein (Gbp) family genes. We show that a cluster of Gbp genes was required for host cellular immunity against the intracellular parasite Toxoplasma gondii. We generated mice deficient for all six Gbp genes located on chromosome 3 (Gbp(chr3)) by targeted chromosome engineering. Mice lacking Gbp(chr3) were highly susceptible to T. gondii infection, resulting in increased parasite burden in immune organs. Furthermore, Gbp(chr3)-deleted macrophages were defective in IFN-γ-mediated suppression of T. gondii intracellular growth and recruitment of IFN-γ-inducible p47 GTPase Irgb6 to the parasitophorous vacuole. In addition, some members of Gbp(chr3) restored the protective response against T. gondii in Gbp(chr3)-deleted cells. Our results suggest that Gbp(chr3) play a pivotal role in anti-T. gondii host defense by controlling IFN-γ-mediated Irgb6-dependent cellular innate immunity.

JAEA is now conducting “Fast Reactor Cycle Technology Development (FaCT)” project for commercialization before 2050s. A demonstration reactor for Japan Sodium-cooled Fast Reactor (JSFR) is planned to start operation around 2025. In the FaCT project, conceptual design study on the demonstration reactor has been performed since FY2007 to determine referential reactor specifications for the next stage of design work of licensing and construction study. Plant performance as a demonstration reactor for the 1.5 GWe commercial reactor JSFR is being compared between 750 MWe and 500 MWe plant designs. In this paper, the current status of the conceptual design study for the demonstration reactor plant is summarized.Copyright © 2010 by ASME

Intensive diabetes treatment causes a considerable increase in the number of severe hypoglycaemic episodes which could aggravate the progression of diabetic neuropathy. However, the effect of repeated hypoglycaemic episodes on nerve morphology has never been previously investigated. The aims of the present study were: (i) to establish a rat model of recurrent episodes of severe hypoglycaemia, and (ii) to assess morphological changes after repeated hypoglycaemic episodes in rat sciatic nerves. We induced hypoglycaemic episodes, blood glucose level

A previous questionnaire study suggested that drug use disorder (DUD: abuse/dependence on drugs, other than alcohol) in Japanese eating disorder (ED) patients was less prevalent than in Western countries, although eating and drug use disorders have spread simultaneously in Western countries. However, the precise prevalence and comorbidity features remain unknown. Subjects consisted of 62 patients with anorexia nervosa restricting type; 48 patients with anorexia nervosa binge eating/purging type; and 75 patients with bulimia nervosa purging type. The Japanese version of the Structured Clinical Interview for DSM-III-R; the Structured Clinical Interview for DSM-III-R Personality Disorders; and the supplement module of the Schedule for Affective Disorders and Schizophrenia-Lifetime version were used for the interview. Sixteen (8.6%, 95% CI = 4.6-12.7%) patients had lifetime diagnoses of DUD. Drugs were solvent fumes or benzodiazepines, and only one patient had been dependent on methamphetamine. More than half of the patients with lifetime DUD diagnoses were multi-impulsivitists. On multivariate analysis, DUD was significantly linked with childhood parental loss, history of conduct disorder and borderline personality disorder. Thus, the prevalence of DUD in Japanese ED patients was indeed lower than that in Western countries. However, similar comorbidity was found in ED patients with DUD compared with that of those in Western countries. The current study suggests that ED and DUD have different origins, although they share the feature of impulsivity. Further study in the general population is needed to clarify these issues.

A 36-year-old woman who had had Graves' disease for 6 years was admitted with severe thrombocytopenia. Evans' syndrome was diagnosed. The patient's family history showed multiple cases of Graves' disease but no cases of Evans' syndrome. Both conditions in this patient improved with corticosteroid and thiamazole therapy. Several autoimmune antibodies were found, but a common autoimmune mechanism was not clearly shown. Although the combination of Graves' disease and Evans' syndrome had not occurred previously in her family, genetic factors may play an important role in the pathogenesis of both conditions.

これまでは包装製品の構造設計について述べてきたが, より個性化, 差別化が求められる現在では, 人間の感性やセンスに頼る部分も多い.例えぼ「一体どのような形が美しいのか」「いままでに見たこともない形のパッケージを作ってみたい」など, 設計者やデザイナーの欲求にこたえてくれるには不十分である.たしかに完成予測をリアルに表示したり, 色を変えてみたり, 質感を変えてみることは重要なファクタではあるが, それはプロセスの一部であり, もっと重要なことは新しいデザインを創造することである.そのようなユニークな発想とデザインが創造でき, 表現することができる全く新しいデザインワークステーションの出現が望まれる.最後に, 当社では印刷という職業柄, 早くからCG関係には目を向け取り組んで来た.その結果, 今では自社開発のシステムを有するに至り, 販売もしているが, CAD/CAMについては歴史が浅く, ようやく今後の進む方向が見えかけてきたところである.従って, 本稿も, 表題に対して的を射ているか少々疑問であるが, その点はご容赦願いたい.近い将来, コンピュータが感性やひらめきを授かり “ニュー・グッド・パッケージ・クリエイター” になるのでは…と夢はふくらむ.

SummaryAlso known as Sqstm1, p62 is a selective autophagy adaptor with a ubiquitin-binding domain. However, the role of p62 in the host defense against Toxoplasma gondii infection is unclear. Here, we show that interferon γ (IFN-γ) stimulates ubiquitin and p62 recruitment to T. gondii parasitophorous vacuoles (PVs). Some essential autophagy-related proteins, but not all, are required for this recruitment. Regardless of normal IFN-γ-induced T. gondii clearance activity and ubiquitination, p62 deficiency in antigen-presenting cells (APCs) and mice diminishes the robust IFN-γ-primed activation of CD8+ T cells that recognize the T. gondii-derived antigen secreted into PVs. Because the expression of Atg3 and Irgm1/m3 in APCs is essential for PV disruption, ubiquitin and p62 recruitment, and vacuolar-antigen-specific CD8+ T cell activation, IFN-γ-mediated ubiquitination and the subsequent recruitment of p62 to T. gondii are specifically required for the acquired immune response after PV disruption by IFN-γ-inducible GTPases.