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N. Tsugawa · SciRah

Researcher profile · Semantic Scholar

N. Tsugawa

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N. Tsugawa — researcher profile on SciRah

h-index: 27
Works: 124
Citations: 2,975

Most-cited papers

Depressed expression of Klotho and FGF receptor 1 in hyperplastic parathyroid glands from uremic patients.
H. Komaba, S. Goto, H. Fujii, Y. Hamada +11 more
2010Kidney International267 citations Open access
Semantic Scholar
Vitamin K content of foods and dietary vitamin K intake in Japanese young women.
M. Kamao, Y. Suhara, N. Tsugawa, Masako Uwano +5 more
2007Journal of Nutritional Science and Vitaminology152 citations Open access
Semantic Scholar
Vitamin K status of healthy Japanese women: age-related vitamin K requirement for gamma-carboxylation of osteocalcin.
N. Tsugawa, M. Shiraki, Y. Suhara, M. Kamao +2 more
2006American Journal of Clinical Nutrition141 citations Open access
Semantic Scholar
Determination of 25-hydroxyvitamin D in human plasma using high-performance liquid chromatography--tandem mass spectrometry.
N. Tsugawa, Y. Suhara, M. Kamao, T. Okano
2005Analytical Chemistry133 citations
Semantic Scholar
Regulation of Type II Renal Na+-dependent Inorganic Phosphate Transporters by 1,25-Dihydroxyvitamin D3
Y. Taketani, H. Segawa, M. Chikamori, K. Morita +10 more
1998Journal of Biological Chemistry126 citations Open access
Semantic Scholar
High prevalence of vitamin K and D deficiency and decreased BMD in inflammatory bowel disease
A. Kuwabara, Kiyoshi Tanaka, N. Tsugawa, H. Nakase +7 more
2009Osteoporosis International119 citations
Semantic Scholar
Method for the determination of vitamin K homologues in human plasma using high-performance liquid chromatography-tandem mass spectrometry.
Y. Suhara, M. Kamao, N. Tsugawa, T. Okano
2005Analytical Chemistry119 citations
Semantic Scholar
Quantification of fat-soluble vitamins in human breast milk by liquid chromatography-tandem mass spectrometry.
M. Kamao, N. Tsugawa, Y. Suhara, A. Wada +7 more
2007Journal of chromatography. B, Analytical technologies in the biomedical and life sciences114 citations
Semantic Scholar
Menadione (Vitamin K3) Is a Catabolic Product of Oral Phylloquinone (Vitamin K1) in the Intestine and a Circulating Precursor of Tissue Menaquinone-4 (Vitamin K2) in Rats*
Yoshihisa Hirota, N. Tsugawa, K. Nakagawa, Y. Suhara +8 more
2013Journal of Biological Chemistry111 citations Open access
Semantic Scholar
Vitamin D status, bone mass, and bone metabolism in home-dwelling postmenopausal Japanese women: Yokogoshi Study.
Kazutoshi Nakamura, N. Tsugawa, Toshiko Saito, Miki Ishikawa +10 more
2008Bone103 citations
Semantic Scholar
Vitamin K Nutrition and Bone Health
N. Tsugawa, M. Shiraki
2020Nutrients95 citations Open access
Semantic Scholar
Low plasma phylloquinone concentration is associated with high incidence of vertebral fracture in Japanese women
N. Tsugawa, M. Shiraki, Y. Suhara, M. Kamao +3 more
2008Journal of Bone and Mineral Metabolism84 citations
Semantic Scholar
Determination of plasma Vitamin K by high-performance liquid chromatography with fluorescence detection using Vitamin K analogs as internal standards.
M. Kamao, Y. Suhara, N. Tsugawa, T. Okano
2005Journal of chromatography. B, Analytical technologies in the biomedical and life sciences82 citations
Semantic Scholar
Functional Characterization of the Vitamin K2 Biosynthetic Enzyme UBIAD1
Yoshihisa Hirota, K. Nakagawa, N. Sawada, Naoko Okuda +7 more
2015PLoS ONE55 citations Open access
Semantic Scholar
Elevated Fibroblast Growth Factor 23 Exerts Its Effects on Placenta and Regulates Vitamin D Metabolism in Pregnancy of Hyp Mice
Y. Ohata, M. Yamazaki, M. Kawai, N. Tsugawa +10 more
2014Journal of Bone and Mineral Research53 citations Open access
Semantic Scholar
High level of serum undercarboxylated osteocalcin in patients with incident fractures during bisphosphonate treatment
M. Shiraki, Y. Yamazaki, Y. Shiraki, T. Hosoi +2 more
2010Journal of Bone and Mineral Metabolism43 citations
Semantic Scholar
Vitamin K2 Biosynthetic Enzyme, UBIAD1 Is Essential for Embryonic Development of Mice
K. Nakagawa, N. Sawada, Yoshihisa Hirota, Yuri Uchino +8 more
2014PLoS ONE40 citations Open access
Semantic Scholar
High prevalence of hypovitaminosis D and K in patients with hip fracture.
T. Nakano, N. Tsugawa, A. Kuwabara, M. Kamao +2 more
2011Asia Pacific Journal of Clinical Nutrition37 citations
Semantic Scholar
The impact of lifestyle factors on serum 25-hydroxyvitamin D levels: a cross-sectional study in Japanese women aged 19–25 years
H. Ohta, T. Kuroda, Y. Onoe, S. Orito +6 more
2009Journal of Bone and Mineral Metabolism36 citations
Semantic Scholar
Regulation of gene expression of epithelial calcium channels in intestine and kidney of mice by 1alpha,25-dihydroxyvitamin D3.
T. Okano, N. Tsugawa, Atsushi Morishita, S. Kato
2004Journal of Steroid Biochemistry and Molecular Biology32 citations
Semantic Scholar
Absorption of calcium, magnesium, phosphorus, iron and zinc in growing male rats fed diets containing either phytate-free soybean protein or soybean protein isolate or casein.
M. Kamao, N. Tsugawa, K. Nakagawa, Y. Kawamoto +5 more
2000Journal of Nutritional Science and Vitaminology30 citations Open access
Semantic Scholar
A simple questionnaire for the prediction of vitamin D deficiency in Japanese adults (Vitaimn D Deficiency questionnaire for Japanese: VDDQ-J)
A. Kuwabara, N. Tsugawa, Kei Mizuno, Honami Ogasawara +2 more
2019Journal of Bone and Mineral Metabolism29 citations
Semantic Scholar
Oral Supplementation of the Vitamin D Metabolite 25(OH)D3 Against Influenza Virus Infection in Mice
Hirotaka Hayashi, M. Okamatsu, Honami Ogasawara, N. Tsugawa +3 more
2020Nutrients28 citations Open access
Semantic Scholar
Cardiovascular Diseases and Fat Soluble Vitamins: Vitamin D and Vitamin K.
N. Tsugawa
2015Journal of Nutritional Science and Vitaminology27 citations Open access
Semantic Scholar
Improvement of vitamin D status in Japanese institutionalized elderly by supplementation with 800 IU of vitamin D(3).
A. Kuwabara, N. Tsugawa, Kiyoshi Tanaka, Minori Fujii +11 more
2009Journal of Nutritional Science and Vitaminology27 citations Open access
Semantic Scholar
Generation of 1,25-dihydroxyvitamin D3 in Cyp27b1 knockout mice by treatment with 25-hydroxyvitamin D3 rescued their rachitic phenotypes.
Miyu Nishikawa, Kaori Yasuda, M. Takamatsu, Keisuke Abe +9 more
2019Journal of Steroid Biochemistry and Molecular Biology26 citations
Semantic Scholar
Association between vitamin D status and serum parathyroid hormone concentration and calcaneal stiffness in Japanese adolescents: sex differences in susceptibility to vitamin D deficiency
N. Tsugawa, K. Uenishi, H. Ishida, R. Ozaki +5 more
2016Journal of Bone and Mineral Metabolism26 citations
Semantic Scholar
Recent advances in vitamin K-dependent Gla-containing proteins and vitamin K nutrition
M. Shiraki, N. Tsugawa, T. Okano
201524 citations Open access
Semantic Scholar
Comparison of Vitamin D and 25-Hydroxyvitamin D Concentrations in Human Breast Milk between 1989 and 2016–2017
N. Tsugawa, Mayumi Nishino, A. Kuwabara, Honami Ogasawara +4 more
2021Nutrients22 citations Open access
Semantic Scholar
High prevalence of vitamin D deficiency in patients with xeroderma pigmetosum-A under strict sun protection
A. Kuwabara, N. Tsugawa, Kiyoshi Tanaka, Y. Uejima +7 more
2015European Journal of Clinical Nutrition22 citations
Semantic Scholar
Hypovitaminosis D and K are highly prevalent and independent of overall malnutrition in the institutionalized elderly.
A. Kuwabara, Masako Himeno, N. Tsugawa, M. Kamao +7 more
2010Asia Pacific Journal of Clinical Nutrition22 citations
Semantic Scholar
Intake of omega-3 fatty acids contributes to bone mineral density at the hip in a younger Japanese female population
T. Kuroda, Hiroaki Ohta, Y. Onoe, N. Tsugawa +1 more
2017Osteoporosis International21 citations
Semantic Scholar
In vitro biological activities of a series of 2β-substituted analogues of 1α, 25-dihydroxyvitamin D3
N. Tsugawa, K. Nakagawa, M. Kurobe, Y. Ono +3 more
200021 citations Open access
Semantic Scholar
Elucidation of metabolic pathways of 25-hydroxyvitamin D3 mediated by CYP24A1 and CYP3A using Cyp24a1 knockout rats generated by CRISPR/Cas9 system
Kaori Yasuda, Miyu Nishikawa, Kairi Okamoto, Kyohei Horibe +10 more
2021Journal of Biological Chemistry20 citations Open access
Semantic Scholar
A novel method based on curvature analysis for estimating the dietary vitamin K requirement in adolescents.
N. Tsugawa, K. Uenishi, H. Ishida, Takuya Minekami +6 more
2012Clinical Nutrition20 citations
Semantic Scholar
Generation of novel genetically modified rats to reveal the molecular mechanisms of vitamin D actions
Miyu Nishikawa, Kaori Yasuda, M. Takamatsu, Keisuke Abe +11 more
2020Scientific Reports19 citations Open access
Semantic Scholar
Nutritional Effects of γ-Glutamyl Carboxylase Gene Polymorphism on the Correlation between the Vitamin K Status and γ-Carboxylation of Osteocalcin in Young Males
N. Sogabe, N. Tsugawa, Rieko Maruyama, M. Kamao +4 more
200719 citations Open access
Semantic Scholar
Nongenomic effects of 1α,25-dihydroxyvitamin D3 on cartilage formation deduced from comparisons between Cyp27b1 and Vdr knockout mice.
Yoshihisa Hirota, K. Nakagawa, Shino Mimatsu, N. Sawada +6 more
2017Biochemical and Biophysical Research Communications - BBRC18 citations Open access
Semantic Scholar
Effects of Fok-I polymorphism in vitamin D receptor gene on serum 25-hydroxyvitamin D, bone-specific alkaline phosphatase and calcaneal quantitative ultrasound parameters in young adults.
Rieko Tanabe, Yuka Kawamura, N. Tsugawa, Mayu Haraikawa +4 more
2015Asia Pacific Journal of Clinical Nutrition18 citations
Semantic Scholar
Menadione ( Vitamin K 3 ) Is a Catabolic Product of Oral Phylloquinone ( Vitamin K 1 ) in the Intestine and a Circulating Precursor of Tissue Menaquinone-4 ( Vitamin K 2 ) in Rats *
Yoshihisa Hirota, N. Tsugawa, K. Nakagawa, Y. Suhara +8 more
201318 citations
Semantic Scholar
Biological Activity Profiles of 1α, 25-Dihydroxyvitamin D2, D3, D4, D7, and 24-Epi-1α, 25-dihydroxyvitamin D2
N. Tsugawa, K. Nakagawa, Y. Kawamoto, Y. Tachibana +3 more
199918 citations Open access
Semantic Scholar
Intestinal absorption of calcium from calcium ascorbate in rats
N. Tsugawa, Takashi Yamabe, A. Takeuchi, M. Kamao +3 more
1999Journal of Bone and Mineral Metabolism18 citations
Semantic Scholar
Vitamin D deficiency as the risk of respiratory tract infections in the institutionalized elderly: A prospective 1-year cohort study.
A. Kuwabara, N. Tsugawa, M. Ao, J. Ohta +1 more
2020Clinical Nutrition ESPEN17 citations
Semantic Scholar
Low calcium intake is associated with increased bone resorption in postmenopausal Japanese women: Yokogoshi Study
Kazutoshi Nakamura, Toshiko Saito, A. Yoshihara, Miki Ishikawa +10 more
2009Public Health Nutrition17 citations Open access
Semantic Scholar
Determination of Fat-Soluble Vitamins in Human Plasma, Breast Milk and Food Samples: Application in Nutrition Survey for Establishment of "Dietary Reference Intakes for Japanese"
M. Kamao, N. Tsugawa, Y. Suhara, T. Okano
200717 citations Open access
Semantic Scholar
“Symmetry” in the synthesis of the a-ring of a vitamin D hybrid analogue with significant transactivation activity: A combinatorial sequence of regioselective propiolate-ene, catalytic enantioselective epoxidation and carbonyl-ene cyclization reactions@
K. Mikami, Ayako Osawa, A. Isaka, Eiji Sawa +6 more
199817 citations
Semantic Scholar
Design and synthesis of biologically active analogues of vitamin K2: evaluation of their biological activities with cultured human cell lines.
Y. Suhara, Yoshihisa Hirota, K. Nakagawa, M. Kamao +2 more
2008Bioorganic & Medicinal Chemistry16 citations
Semantic Scholar
Singly dehydroxylated A-ring analogues of 19-nor-1alpha,25-dihydroxyvitamin D3 and 19-nor-22-oxa-1alpha,25-dihydroxyvitamin D3: novel vitamin D3 analogues with potent transcriptional activity but extremely low affinity for vitamin D receptor.
Toshio Okano, K. Nakagawa, N. Tsugawa, Keiichi Ozono +4 more
1998Biological and Pharmaceutical Bulletin15 citations Open access
Semantic Scholar
25-Hydroxyvitamin D profiles and maternal bone mass during pregnancy and lactation in Japanese women
Hiromi Yoshikata, N. Tsugawa, Yuna Watanabe, T. Tsuburai +6 more
2019Journal of Bone and Mineral Metabolism13 citations
Semantic Scholar
Hypovitaminosis D is frequent in Japanese subjects with type 2 diabetes.
H. Koshiyama, H. Ikeda, Sachiko Honjo, Yoshio Nakamura +3 more
2007Diabetes Research and Clinical Practice13 citations
Semantic Scholar

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T. Okano×39
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T. Okano — researcher profile on SciRah
M. Kamao×23
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M. Kamao — researcher profile on SciRah
K. Nakagawa×15
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K. Nakagawa — researcher profile on SciRah
Y. Suhara×14
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Y. Suhara — researcher profile on SciRah

×11

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Kiyoshi Tanaka — researcher profile on SciRah

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A. Kuwabara — researcher profile on SciRah

Yoshihisa Hirota×8

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Yoshihisa Hirota — researcher profile on SciRah

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K. Uenishi — researcher profile on SciRah

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M. Shiraki — researcher profile on SciRah

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Yuri Uchino — researcher profile on SciRah

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N. Sawada — researcher profile on SciRah

Toshio Okano×4

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Toshio Okano — researcher profile on SciRah