Sachiko Takehara

Prof. Dr. Sachiko Takehara

Department of preventive dentistry, Niigata University Graduate School of Health Sciences, Niigata, Japan
orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

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

Representative Publications

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12 February 2010 in Trials
Verified
Journal Article
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KSKayoko Shinada
Kayoko Shinada
MUMasayuki Ueno
Masayuki Ueno
CKChisato Konishi
Chisato Konishi
STSachiko Takehara
Sachiko Takehara
SYSayaka Yokoyama
Sayaka Yokoyama
YKYoko Kawaguchi
Yoko Kawaguchi
Previous research has shown the oxidizing properties and microbiological efficacies of chlorine dioxide (ClO2). Its clinical efficacies on oral malodor have been evaluated and reported only in short duration trials, moreover, no clinical studies have investigated its microbiological efficacies on periodontal and malodorous bacteria. Thus, the aim of this study was to assess the inhibitory effects of a mouthwash containing ClO2 used for 7 days on morning oral malodor and on salivary periodontal and malodorous bacteria.

18 July 2013 in PLOS ONE
Verified
Journal Article
Open access
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STSachiko Takehara
Sachiko Takehara
MYMasaki Yanagishita
Masaki Yanagishita
KPKatarzyna Anna Podyma-Inoue
Katarzyna Anna Podyma-Inoue
YKYoko Kawaguchi
Yoko Kawaguchi
Two types of mucins, MUC7 and MUC5B constitute the major salivary glycoproteins, however their metabolic turnover has not been elucidated in detail to date. This study was conducted to examine turnover of MUC7 and MUC5B in saliva, by focusing on the relationship between their deglycosylation and proteolysis. Whole saliva samples were collected from healthy individuals and incubated at 37°C in the presence of various protease inhibitors, sialidase, or a sialidase inhibitor. General degradation patterns of salivary proteins and glycoproteins were examined by SDS-polyacrylamide-gel-electrophoresis. Furthermore, changes of molecular sizes of MUC7 and MUC5B were examined by Western blot analysis. A protein band was identified as MUC7 by Western blot analysis using an antibody recognizing an N-terminal epitope. The MUC7 signal disappeared rapidly after 20-minutes of incubation. In contrast, the band of MUC7 stained for its carbohydrate components remained visible near its original position for a longer time indicating that the rapid loss of Western blot signal was due to the specific removal of the N-termimal epitope. Pretreatment of saliva with sialidase facilitated MUC7 protein degradation when compared with samples without treatment. Furthermore, addition of sialidase inhibitor to saliva prevented proteolysis of N-terminus of MUC7, suggesting that the desialylation is a prerequisite for the degradation of the N-terminal region of MUC7. The protein band corresponding to MUC5B detected in both Western blotting and glycoprotein staining showed little sign of significant degradation upon incubation in saliva up to 9 hours. MUC7 was highly susceptible to specific proteolysis in saliva, though major part of MUC5B was more resistant to degradation. The N-terminal region of MUC7, particularly sensitive to proteolytic degradation, has also been proposed to have distinct biological function such as antibacterial activities. Quick removal of this region may have biologically important implication.

9 December 2008 in Trials
Verified
Journal Article
Open access
PDF file
KSKayoko Shinada
Kayoko Shinada
MUMasayuki Ueno
Masayuki Ueno
CKChisato Konishi
Chisato Konishi
STSachiko Takehara
Sachiko Takehara
SYSayaka Yokoyama
Sayaka Yokoyama
YKYoko Kawaguchi
Yoko Kawaguchi
Previous research has shown the oxidizing properties and microbiological efficacies of chlorine dioxide (ClO2), however, its clinical efficacies on oral malodor have been evaluated only with organoleptic measurements (OM) or sulphide monitors. No clinical studies have investigated the inhibitory effects of ClO2 on volatile sulfur compounds (VSCs) using gas chromatography (GC). The aim of this study was to assess the inhibitory effects of a mouthwash containing ClO2 on morning oral malodor using OM and GC.

STSachiko Takehara
Sachiko Takehara
RKRaksanan Karawekpanyawong
Raksanan Karawekpanyawong
HOHikaru Okubo
Hikaru Okubo
TTTin Zar Tun
Tin Zar Tun
ARAulia Ramadhani
Aulia Ramadhani
HOHiroshi Ogawa
Hiroshi Ogawa
(1) Background: The aim of this study is to review the benefits of the 8020 Campaign since its inception. (2) Methods: We followed the PRISMA guideline and collected information regarding the 8020 Campaign through online database searches. (3) Results: Twenty-five studies met the inclusion criteria and were eligible for analysis. The main outcomes of the 25 included studies were reviewed. The quality evaluation demonstrated a range of studies showing a credible relationship between masticatory function, number of teeth, salivary secretion, frequent dental check-ups, and general health concerns. Due to the risk of bias, publication bias, and indirectness, 22 studies were considered that only had “fair” quality. (4) Conclusions: The 8020 Foundation funded several of the studies, and other research papers noted the 8020 Campaign in their papers, however there were no clear explanations for any direct relationship between their findings and the 8020 Campaign. As a result, evidence for the direct effectiveness and benefits assessment of the 8020 Campaign positive outcomes were compromised by confounding social and economic variables over the 30-year period. To fully elucidate how improvement in Japan’s oral health was directly related to the 8020 Campaign, a more informed and systematic explanation of the campaign’s structure and activities is required.

16 April 2021 in BMC Geriatrics
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Journal Article
Open access
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STSachiko Takehara
Sachiko Takehara
VHVasant Hirani
Vasant Hirani
FWF. A. Clive Wright
F. A. Clive Wright
VNVasi Naganathan
Vasi Naganathan
FBFiona M. Blyth
Fiona M. Blyth
RCRobert G. Cumming
Robert G. Cumming
Background: Unintended weight loss and the reduction in appetite are common phenomenon among older people. Reduced appetite has been linked to medication related reductions in saliva production, reduced taste ability and poor oral health. Poor appetite can result in reduced nutrient intake ensuing weight loss. It is possible that poor appetite is a mediating step on the causal pathway between oral health and weight loss. This study investigates whether poor oral health and loss of appetite are related to weight loss. Methods: This is an observational study where data were obtained from the Concord Health and Ageing in Men Project (CHAMP). Information on socio-demographics, appetite and health related behavior was collected by self-completed questionnaire. Intraoral assessment was conducted by calibrated oral health therapists. Height and weight were measured by trained staff. Regression analysis investigated associations between oral health and appetite as risk factors for weight loss. Results: Participants included 542 community dwelling older males. 99 older men (18.3%) experienced 5% or more weight loss over 3 years. Men who lost weight from baseline had lower BMI and lower body weight, had higher prevalence of frailty and depression, reported poorer appetite, and had fewer teeth (13.8 ± 9.5) than those who did not lose weight (16.3 ± 9.3). Before adjustment, the prevalence ratio (PR) for weight loss was 1.76 (95% Confidence Interval (CI), 1.19–2.59) for participants with 0–19 natural teeth present compared to those with 20 or more teeth. When adding appetite and other variables to the model, the PR for number of teeth and weight loss was unchanged: 1.78 (95% CI, 1.06–3.00). The mediation analysis showed that the indirect effect of appetite on the association between number of natural teeth on weight loss was not found to be significant. Conclusion: This study found that number of natural teeth present and appetite are independently related to weight change among elderly men in Australia. Tooth loss can increase the risk of swallowing difficulty leading to change in food preference, avoidance of foods and a decrease in energy intake. Our study showed the importance of oral health interventions to encourage maintenance of 20 or more natural teeth in older people.

7 February 2019 in PLOS ONE
Verified
Journal Article
Open access
PDF file
STSachiko Takehara
Sachiko Takehara
JZJorge L Zeredo
Jorge L Zeredo
YKYasuhiro Kumei
Yasuhiro Kumei
KKKensuke Kagiyama
Kensuke Kagiyama
KFKazumasa Fukasawa
Kazumasa Fukasawa
YKYoko Kawaguchi
Yoko Kawaguchi
With rapid aging of the world’s population, the demand for research, for a better understanding of aging and aging-related disorders, is increasing. Ideally, such research should be conducted on human subjects. However, due to ethical considerations, animals such as rodents and monkeys are used as alternatives. Among these alternative models, non-human primates are preferred because of their similarities with humans. The small South American common marmoset (Callithrix jacchus) may offer several advantages over other non-human primates in terms of its smaller size, shorter life-span, and dental anatomy identical to humans. The purpose of this study was to determine the viability of using the marmoset as a human oral disease model. We collected saliva samples from eight marmosets and eight human subjects. Prokaryotic DNA was extracted from the saliva samples, and 16S bacterial rRNA gene sequencing was performed on each of the samples. Our results indicated that the types of oral microbiomes detected among human and marmoset samples were nearly indistinguishable. In contrast, the oral microbiomes of our human and marmoset subjects were distinctly different from those reported for rats and dogs, which are currently popular research animals. The oral microbiomes of marmosets showed greater diversity than those of humans. However, the oral microbiota of marmosets exhibited less variation than those of humans, which may be attributed to the fact that the marmoset subjects were kept in a controlled environment with identical lifestyles. The characteristics of its oral microbiota, combined with other technical advantages, suggest that the marmoset may provide the best animal model thus far for the study of oral health. This study characterized the oral microbes of the marmoset, thereby providing information to support future application of the marmoset as a model for age-related oral disease.