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Fulltext Development, validation and utilisation of dish-based dietary assessment tools: a scoping review

Shinozaki N, Yuan X, Murakami K, Sasaki S

Public Health Nutr, 2021 Feb;24(2):223-242.
PMID: 32758321 DOI: 10.1017/S136898002000172X

OBJECTIVE: To summarise the existing evidence of development, validation and current status of utilisation of dish-based dietary assessment tools.
DESIGN: Scoping review.
SETTING: Systematic search using PubMed and Web of Science.
RESULTS: We identified twelve tools from seventy-four eligible publications. They were developed for Koreans (n 4), Bangladeshis (n 2), Iranians (n 1), Indians/Malays/Chinese (n 1), Japanese (n 3) and Chinese Americans (n 1). Most tools (10/12) were composed of a dish-based FFQ. Although the development process of a dish list varied among the tools, six studies classified mixed dishes based on the similarity of their characteristics such as food ingredients and cooking methods. Tools were validated against self-reported dietary information (n 9) and concentration biomarkers (n 1). In the eight studies assessing the differences between the tool and a reference, the mean (or median) intake of energy significantly differed in five studies, and 26-83 % of nutrients significantly differed in eight studies. Correlation coefficients for energy ranged from 0·15 to 0·87 across the thirteen studies, and the median correlation coefficients for nutrients ranged from 0·12 to 0·77. Dish-based dietary assessment tools were used in fifty-nine studies mainly to assess diet-disease relationships in target populations.
CONCLUSIONS: Dish-based dietary assessment tools have exclusively been developed and used for Asian-origin populations. Further validation studies, particularly biomarker-based studies, are needed to assess the applicability of tools.
Fulltext Development of MTH1-Binding Nucleotide Analogs Based on 7,8-Dihalogenated 7-Deaza-dG Derivatives

Shi H, Ishikawa R, Heh CH, Sasaki S, Taniguchi Y

Int J Mol Sci, 2021 Jan 28;22(3).
PMID: 33525366 DOI: 10.3390/ijms22031274

MTH1 is an enzyme that hydrolyzes 8-oxo-dGTP, which is an oxidatively damaged nucleobase, into 8-oxo-dGMP in nucleotide pools to prevent its mis-incorporation into genomic DNA. Selective and potent MTH1-binding molecules have potential as biological tools and drug candidates. We recently developed 8-halogenated 7-deaza-dGTP as an 8-oxo-dGTP mimic and found that it was not hydrolyzed, but inhibited enzyme activity. To further increase MTH1 binding, we herein designed and synthesized 7,8-dihalogenated 7-deaza-dG derivatives. We successfully synthesized multiple derivatives, including substituted nucleosides and nucleotides, using 7-deaza-dG as a starting material. Evaluations of the inhibition of MTH1 activity revealed the strong inhibitory effects on enzyme activity of the 7,8-dihalogenated 7-deaza-dG derivatives, particularly 7,8-dibromo 7-daza-dGTP. Based on the results obtained on kinetic parameters and from computational docking simulating studies, these nucleotide analogs interacted with the active site of MTH1 and competitively inhibited the substrate 8-oxodGTP. Therefore, novel properties of repair enzymes in cells may be elucidated using new compounds.
Phytochemical survey of Malaysian plants preliminary chemical and pharmacological screening

Nakanishi K, Sasaki S, Kiang AK, Goh J, Kakisawa H, Ohashi M, et al.

Chem Pharm Bull (Tokyo), 1965 Jul;13(7):882-90.
PMID: 5867816
Synthesis of γ-N-modified 8-oxo-2'-deoxyguanosine triphosphate and its characterization

Thavoncharoensub N, Maruyama K, Heh CH, Hoong Leong K, Shi H, Shigematsu Y, et al.

Nucleosides Nucleotides Nucleic Acids, 2019;38(8):578-589.
PMID: 30929604 DOI: 10.1080/15257770.2019.1586919

8-OxodGTP is generated by the reaction between dGTP and reactive oxygen species and a considered mutagenic nucleotide. It can be incorporated into the duplex DNA during replication processes by the DNA polymerase, and thus the repair enzyme removes oxodGTP from the nucleotide pools in living cells. On the other hand, the γ-modified triphosphates show interesting properties for use as biological tools. Therefore, the γ-N-pyrenylalkyl-oxodGTP derivatives were synthesized and their effect on the enzymatic reactions were evaluated. The γ-N-pyrenylmethyl-oxodGTP was found to be accepted by the DNA polymerase just like oxodGTP, but showed a competitive inhibition property for the human oxodGTPase.