Publications by authors named "Ryoki Kobayashi"

Article Synopsis
  • - This study examines how data augmentation using generative adversarial networks (GANs) can enhance the prediction of dementia risk through deep neural networks (DNNs), specifically focusing on blood test and periodontal examination data.
  • - Challenges in creating accurate models include high costs, limited sample sizes, and missing data from various tests, which can hinder effective dementia risk predictions.
  • - The results showed that DNNs using GAN-synthesised data outperformed those using real data, with improved accuracy and robustness against missing information, indicating a promising avenue for better dementia risk prediction methods.
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Article Synopsis
  • The study examines the use of data augmentation techniques to enhance the prediction of dementia risk through machine learning models, specifically focusing on easily obtainable blood test results and periodontal examination data.
  • It employs advanced techniques like SMOGN, GAN, and CTGAN on datasets comprising cognitive assessments, demographics, and test results, utilizing various machine learning models for evaluation.
  • Findings indicate that while normal GANs improve data diversity, CTGANs better preserve data structure, significantly enhancing the performance of linear regression models when applied to synthesized data.
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The female reproductive tract (FRT) and remote/versatile organs in the body share bidirectional communication. In this review, we discuss the framework of the "FRT-organ axes." Each axis, namely, the vagina-gut axis, uterus-gut axis, ovary-gut axis, vagina-bladder axis, vagina-oral axis, uterus-oral axis, vagina-brain axis, uterus-brain axis, and vagina-joint axis, is comprehensively discussed separately.

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Nutritional factors reflect the periodontal parameters accompanying periodontal status. In this study, the associations between nutritional factors, blood biochemical items, and clinical parameters were examined in patients with systemic diseases. The study participants were 94 patients with heart disease, dyslipidemia, kidney disease, or diabetes mellitus.

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The recurrence risk evaluation has been emphasized in periodontal stabilization during supportive periodontal therapy (SPT). However, nutritional factors, e.g.

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It has been reported that GroEL, a heat shock protein (HSP) produced by the representative periodontopathogenic bacterium, Porphyromonas gingivalis, induces inflammation-induced osteoclastogenesis and promotes alveolar bone resorption. In this study, we demonstrated the efficacy of a mucosal vaccine targeting GroEL against bone resorption induced by P. gingivalis.

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Background And Objective: Recent studies have shown a link between periodontal disease and cardiovascular disease. We have previously reported that oral administration of Porphyromonas gingivalis (Pg) accelerates atherosclerosis in apolipoprotein E-deficient spontaneously hyperlipidemic (Apoe ) mice. This study evaluated the potential of lactic acid bacteria (LAB) to change the intestinal flora changes induced by periodontopathic bacteria and to prevent/slow down the development of atherosclerosis.

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Objective: Secreted IgA (SIgA) plays a central role in preventing bacterial and viral infections on mucosal surfaces by neutralizing toxins and viruses and inhibiting bacterial attachment to epithelial cells. However, the role of salivary SIgA antibodies (Abs) in regulating oral flora is still unknown. This study aimed to evaluate the association among oral bacteria, their metabolites and periodontitis in IgA-deficient (IgA KO) and wild-type (WT) control mice.

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Recently, it has been suggested that the oral administration of Porphyromonas gingivalis, a keystone pathogen for periodontal disease, induces dysbiosis of the mouse intestinal microbiota and affects intestinal barrier function. Since oral streptococci are the predominant oral bacterial group, we compared the effect of their oral administration on the intestinal tract compared to that of P. gingivalis.

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Atherosclerosis is exacerbated by periodontal pathogens, which induce vascular inflammation after entering the bloodstream. Among oral indigenous bacteria, Streptococcus sanguinis and S. anginosus are related to systemic disorders, such as infective endocarditis and abscess, and are sometimes detected in human atherosclerotic plaques or blood.

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Antimicrobial peptides play important roles in the innate immune system of various organisms, and they may also be considered to prevent the organisms from infections. In particular, β-defensins, mainly produced in epithelial cells, are recognized as one of the major antimicrobial peptides in mammals, including humans. In this study, we showed that Lactobacillus helveticus SBT2171 (LH2171), one of the several species of lactic acid bacteria, upregulates the production of β-defensins in oral epithelial cells in vitro.

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The migration of antigen (Ag)-loading dendritic cells (DCs) from Peyer's patches (PPs) to the draining mesenteric lymph nodes (MLNs) via chemokine receptor 7 (CCR7) is thought to be an important step in the initiation of acquired immunity. Our previous study showed that PPs were indispensable for Ag-specific secretory (S)IgA antibody (Ab) responses against oral recombinant Salmonella (rSalmonella). In this study, we attempted to show direct PP DC migration to MLNs by employing photoconvertible protein transgenic mice and investigated the role of the CCR7 signaling pathway in mucosal IgA induction.

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Junctional epithelium (JE) develops from reduced enamel epithelium during tooth formation and is critical for the maintenance of healthy periodontal tissue through ensuring appropriate immune responses and the rapid turnover of gingival epithelial cells. We have previously shown a relationship between inflammatory cytokines and expression of JE-specific genes, such as amelotin (AMTN), in gingival epithelial cells. Here, we elucidated the effects of -derived lipopolysaccharide ( LPS) on gene transcription and the interaction of transcription factors.

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In this study, Strain [corrected] SK-1(T), a novel gram-positive, pleomorphic, rod-shaped, non-spore forming, non-motile organism, designated SK-1 , was isolated from human gingival sulcus and found to produce acetic acid, propionic acid, lactic acid, and succinic acid as end products of glucose fermentation. Strain SK-1 is most closely related to Pseudopropionibacterium (Propionibacterium) propionicum with sequence homologies of the 16S rRNA and RNA polymerase β subunit (rpoB) genes of 96.6% and 93.

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Article Synopsis
  • The study investigates the localization of three proteins—amelotin (AMTN), odontogenic ameloblast-associated protein (ODAM), and follicular dendritic cell-secreted protein (FDC-SP)—in the junctional epithelium of mice infected with bacteria and inflamed human gum tissue.
  • It was found that while AMTN and FDC-SP expressions were initially stronger in the P. gingivalis infected mice, these levels decreased as inflammation progressed, whereas ODAM levels remained elevated during the inflammation.
  • In human samples, AMTN was consistently present in both inflamed and non-inflamed gums, while ODAM and FDC-SP were more prevalent in healthy tissue but spread into inflamed areas, suggesting these proteins
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Objective: Porphyromonas gingivalis is involved in the pathogenesis of chronic inflammatory periodontal disease. Recent studies have suggested that the NLRP3 inflammasome plays an important role in the development of chronic inflammation. We investigated a possible association between the inflammasome in gingival inflammation and bone loss induced by P.

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Porphyromonas gingivalis has been shown to accelerate atherosclerotic lesion development in hyperlipidemic animals. Atherosclerosis is a disease characterized by inflammation of the arterial wall. Recent studies have suggested that the NLRP3 inflammasome plays an important role in the development of vascular inflammation and atherosclerosis.

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Objectives: Porphyromonas gingivalis has been shown to associate with the development of atherosclerosis. Recent studies indicate that IL-17-producing T helper 17 (Th17) cells have been correlated with the emergence of atherosclerosis. Therefore, we investigated whether the Th17 cell response and expression of Th17-related molecules, in contrast with Th1- and Treg cells, are enhanced by P.

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Anaphylactic shock is characterized by increased capillary permeability and a decline in blood pressure due to excessive production of IgE. Midazolam (MDZ) is reported to have immunomodulatory properties. However, little is known about the effect of MDZ on the production of IgE antibody.

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Previous studies have demonstrated that nasal administration of the outer membrane protein of Porphyromonas gingivalis (40k-OMP) with cholera toxin (CT) as an adjuvant elicits protective immune responses against P. gingivalis in young mice. In the present study, we investigated whether administration of 40k-OMP plus CT would also induce 40k-OMP-specific antibody (Ab) responses to provide protective immunity against P.

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Our previous studies have shown that Peyer's patches (PPs) play a key role in the induction of oral tolerance. Therefore, we hypothesized that PPs are an important site for Transforming Growth Factor (TGF)-β signaling and sought to prove that this tissue is of importance in oral tolerance induction. We found that expression of TGF-β type II receptor (TGFβRII) by CD4(+) T cells increases and persists in the PPs of normal C57BL/6 mice after either high- or low-dose feeding of OVA when compared to mesenteric lymph nodes (MLNs) and spleen.

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This study demonstrated that sublingual immunization with a fusion protein, 25k-hagA-MBP, which consists of a 25-kDa antigenic region of hemagglutinin A purified from Porphyromonas gingivalis fused to maltose-binding protein (MBP) originating from Escherichia coli as an adjuvant, elicited protective immune responses. Immunization with 25k-hagA-MBP induced high levels of antigen-specific serum IgG and IgA, as well as salivary IgA. High level titers of serum IgG and IgA were also induced for almost 1 year.

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Objective: Porphyromonas gingivalis has been shown to accelerate atherosclerotic lesion development in atherosclerotic apo E-deficient mice. Here, we investigated whether repeated P. gingivalis injection affected the inflammatory and atherosclerotic responses of C57BL/6 mice fed a high-fat diet (HFD).

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Native cholera toxin (nCT) as a nasal adjuvant was shown to elicit increased levels of T-independent S-IgA antibody (Ab) responses through IL-5- IL-5 receptor interactions between CD4+ T cells and IgA+ B-1 B cells in murine submandibular glands (SMGs) and nasal passages (NPs). Here, we further investigate whether oral-nasopharyngeal dendritic cells (DCs) play a central role in the induction of B-1 B cell IgA class switch recombination (CSR) for the enhancement of T cell-independent (TI) mucosal S-IgA Ab responses. High expression levels of activation-induced cytidine deaminase, Iα-Cμ circulation transcripts and Iμ-Cα transcripts were seen on B-1 B cells purified from SMGs and NPs of both TCRβ⁻/⁻ mice and wild-type mice given nasal trinitrophenyl (TNP)-LPS plus nCT, than in the same tissues of mice given nCT or TNP-LPS alone.

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