Takayuki Maruyama

Dr. Takayuki Maruyama

orcid

Research Focus & Metrics

Academic Career Length

37Years (1990-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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Journal Article
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TMTatsuya Machida
Tatsuya Machida
Takaaki TomofujiTakaaki Tomofuji
Takaaki Tomofuji
DEDaisuke Ekuni
Daisuke Ekuni
TMTakayuki Maruyama
Takayuki Maruyama
TYToshiki Yoneda
Toshiki Yoneda
Manabu MoritaManabu Morita
Manabu Morita
The aim of this study was to examine whether salivary exosomal miRNAs could be identified as aging biomarkers. Fifteen young healthy volunteers (median age, 21.0 years) and 13 old individuals (median age, 66.0 years) were recruited. Unstimulated whole saliva was collected, salivary exosomes were isolated, and total RNA was extracted. In a microarray, 242 miRNAs were commonly detected in these two mixed samples. Based on the cut-off values of 2- or 0.5-fold changes (FC) and regulatory power for aging process, six candidate miRNAs (miR-24-3p, miR-371a-5p, miR-3175, miR-3162-5p, miR-671-5p, and miR-4667-5p) were selected. After comparing each total RNA obtained by the 15 young and 13 old individuals to validate the FC values using quantitative real-time PCR, miR-24-3p was identified as a novel candidate aging biomarker. This pilot study suggested that salivary exosomal miRNAs could be identified as candidate aging biomarkers. To confirm whether miR-24-3p in salivary exosomes are suitable biomarkers of aging, further validation research is required.

16 November 2017 in PLOS ONE
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HMHirofumi Mizuno
Hirofumi Mizuno
DEDaisuke Ekuni
Daisuke Ekuni
TMTakayuki Maruyama
Takayuki Maruyama
KKKota Kataoka
Kota Kataoka
TYToshiki Yoneda
Toshiki Yoneda
MMManabu Morita
Manabu Morita
The purpose of this study was to investigate the effects of non-surgical periodontal treatment on hemoglobinA1c (HbA1c) levels, oxidative stress balance and quality of life (QOL) in patients with type 2 diabetes mellitus (T2DM) compared to no periodontal treatment (simple oral hygiene instructions only). The design was a 6-month, single-masked, single center, randomized clinical trial. Patients had both T2DM and chronic periodontitis. Forty participants were enrolled between April 2014 and March 2016 at the Nephrology, Diabetology and Endocrinology Department of Okayama University Hospital. The periodontal treatment group (n = 20) received non-surgical periodontal therapy, including scaling and root planing plus oral hygiene instructions, and consecutive supportive periodontal therapy at 3 and 6 months. The control group (n = 17) received only oral hygiene instructions without treatment during the experimental period. The primary study outcome was the change in HbA1c levels from baseline to 3 months. Secondary outcomes included changes in oxidative stress balance (Oxidative-INDEX), the Diabetes Therapy-Related QOL and clinical periodontal parameters from baseline to 3 months and baseline to 6 months. Changes in HbA1c in the periodontal treatment group were not significantly different with those in the control group at 3 and 6 months. Systemic oxidative stress balance and QOL significantly improved in the periodontal treatment group compared to the control group at 3 months. In the subgroup analysis (moderately poor control of diabetes), the decrease in HbA1c levels in the periodontal treatment group was greater than that in the control group at 3 months but not significant. In T2DM patients, non-surgical periodontal treatment improved systemic oxidative stress balance and QOL, but did not decrease HbA1c levels at 3 months follow-up. Current Controlled Trials UMIN-ICDR UMIN 000013278 (Registered April 1, 2014).

15 March 2019 in Molecules
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KFKohei Fujimori
Kohei Fujimori
TYToshiki Yoneda
Toshiki Yoneda
Takaaki TomofujiTakaaki Tomofuji
Takaaki Tomofuji
DEDaisuke Ekuni
Daisuke Ekuni
TATetsuji Azuma
Tetsuji Azuma
Manabu MoritaManabu Morita
Manabu Morita
The purpose of this cross-sectional pilot study was to find salivary microRNAs (miRNAs) reflecting periodontal condition in chronic periodontitis. One hundred and twenty chronic periodontitis patients (mean age, 68.4 years) participated in the study, from whom unstimulated whole saliva was collected. A multiphase study was conducted to explore salivary miRNAs as biomarkers of periodontitis. At first, a polymerase chain reaction (PCR) array was performed to compare salivary miRNAs profiles in no and mild (no/mild) and severe periodontitis patients. Next, the relative expression of salivary miRNAs on individual samples was assessed by real-time reverse transcription-PCR. The numbers (%) of patients were 26 (21.6%, no/mild), 58 (48.3%, moderate) and 36 (30.0%, severe), respectively. Among 84 miRNAs, only the relative expression of hsa-miR-381-3p in the severe periodontitis group was significantly higher than that of the no/mild periodontitis group (p < 0.05). Among the 120 patients, there was also a significant correlation between the relative expression of hsa-miR-381-3p and the mean probing pocket depth (PPD) (r = 0.181, p < 0.05). Salivary hsa-miR-381-3p was correlated with periodontitis condition in chronic periodontitis patients.

21 October 2014 in Nutrients
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TMTatsuya Machida
Tatsuya Machida
Takaaki TomofujiTakaaki Tomofuji
Takaaki Tomofuji
DEDaisuke Ekuni
Daisuke Ekuni
TATetsuji Azuma
Tetsuji Azuma
NTNoriko Takeuchi
Noriko Takeuchi
Manabu MoritaManabu Morita
Manabu Morita
This cross-sectional study addressed the relationship between coffee consumption and periodontitis in patients during the maintenance phase of periodontal treatment. A total of 414 periodontitis patients in the maintenance phase of periodontal treatment completed a questionnaire including items related to coffee intake and underwent periodontal examination. Logistic regression analysis showed that presence of moderate/severe periodontitis was correlated with presence of hypertension (Odds Ratio (OR) = 1.99, p < 0.05), smoking (former, OR = 5.63, p < 0.01; current, OR = 6.81, p = 0.076), number of teeth present (OR = 0.89, p < 0.001), plaque control record ≥20% (OR = 1.88, p < 0.05), and duration of maintenance phase (OR = 1.07, p < 0.01). On the other hand, presence of severe periodontitis was correlated with smoking (former, OR = 1.35, p = 0.501; current, OR = 3.98, p < 0.05), coffee consumption (≥1 cup/day, OR = 0.55, p < 0.05), number of teeth present (OR = 0.95, p < 0.05), and bleeding on probing ≥ 20% (OR = 3.67, p < 0.001). There appears to be an inverse association between coffee consumption (≥1 cup/day) and prevalence of severe periodontitis in the maintenance phase of periodontal treatment.

9 July 2001 in Bioorganic & Medicinal Chemistry Letters
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Journal Article
Closed access
TMToru Maruyama
Toru Maruyama
MAMasaki Asada
Masaki Asada
TSTai Shiraishi
Tai Shiraishi
AIAkiharu Ishida
Akiharu Ishida
HEHiromu Egashira
Hiromu Egashira
MTMasaaki Toda
Masaaki Toda

31 August 2011 in Arthritis & Rheumatism
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TSToshiko Shibata-Nozaki
Toshiko Shibata-Nozaki
HIHiroshi Ito
Hiroshi Ito
HMHirofumi Mitomi
Hirofumi Mitomi
JAJun Akaogi
Jun Akaogi
TKTatsuya Komagata
Tatsuya Komagata
HYHidehiro Yamada
Hidehiro Yamada
Objective We recently developed an ex vivo cellular model of pannus, the aberrant overgrowth of human synovial tissue. This study was undertaken to use that model to investigate the role of prostaglandin E2 (PGE2) and its receptor subtypes in the development of pannus growth and osteoclast activity in rheumatoid arthritis (RA). Methods Inflammatory cells that infiltrated pannus from patients with RA were collected without enzyme digestion and designated synovial tissue–derived inflammatory cells. Their single-cell suspensions were cultured in medium alone to observe an aberrant overgrowth of inflammatory tissue in vitro. Levels of cytokines produced in culture supernatants were measured using enzyme-linked immunosorbent assay kits. Osteoclast activity was assessed by the development of resorption pits in calcium phosphate–coated slides. Results Primary culture of the synovial tissue–derived inflammatory cells resulted in spontaneous reconstruction of inflammatory tissue in vitro within 4 weeks, during which tumor necrosis factor α, PGE2, macrophage colony-stimulating factor, and matrix metalloproteinase 9 were produced in the supernatant. This aberrant overgrowth was inhibited by antirheumatic drugs including methotrexate and infliximab. On calcium phosphate–coated slides, synovial tissue–derived inflammatory cells showed numerous resorption pits. In the presence of inhibitors of endogenous prostanoid production such as indomethacin and NS398, exogenous PGE1 and EP4-specific agonists significantly inhibited all these activities of synovial tissue–derived inflammatory cells in a dose-dependent manner. Addition of indomethacin, NS398, or EP4-specific antagonist resulted in the enhancement of these cells' activities. EP2-specific agonist had a partial effect, while EP1- and EP3-specific agonists had no significant effects. Conclusion These results suggest that endogenous PGE2 produced in rheumatoid synovium negatively regulates aberrant synovial overgrowth and the development of osteoclast activity via EP4.