Masumi Ai

Prof. Dr. Masumi Ai


Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

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

Representative Publications

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1 September 2021 in Journal of Atherosclerosis and Thrombosis
Verified
Journal Article
Open access
PDF file
MNMarie Nakamura
Marie Nakamura
YYYasushi Yamamoto
Yasushi Yamamoto
WIWataru Imaoka
Wataru Imaoka
TKToshio Kuroshima
Toshio Kuroshima
RTRyoko Toragai
Ryoko Toragai
MAMasumi Ai
Masumi Ai
Aims: Smoking is a major risk factor for cardiovascular disease (CVD), a leading cause of death and disability. Other CVD risk factors include age, gender, hypertension, diabetes, increased low-density lipoprotein cholesterol (LDL-C) and decreased high-density lipoprotein cholesterol (HDL-C). Our goal was to assess relationships between smoking status and CVD risk factors, with a focus on direct LDL-C, HDL-C, triglycerides (TG) and small dense LDL-C (sdLDL-C). Methods: A total of 34,497 Japanese men and women, mean age 51 years, had their CVD risk factors including fasting serum total cholesterol, TG, HDL-C, sdLDL-C, and direct LDL-C assessed. One-way ANOVA and multiple linear regression analyses were carried to assess the interrelationships of these parameters with smoking. Results: In both men and women, current smokers had significantly (p<0.001) higher median TG (+19.6%, +16.9%) and sdLDL-C levels (+12.7%, +4.2%) levels, and significantly (p<0.001) lower HDL-C levels (-7.3%, -4.3%) than non-smokers. They were also significantly (p<0.05) more likely to have TG values >150 mg/dL (+56.8%, +116.3%), sdLDL-C >40.1 mg/dL (+28.8%, +44.9%), and HDL-C <40 mg/dL (+89.8%, +114.3%). Ex-smokers generally had lipid values that were intermediate between non-smokers and current smokers. Multivariate analysis confirmed the significance of these relationships. Conclusion: Our data indicate that current cigarette smoking is associated with increased TG and sdLDL-C levels, as well as decreased HDL-C levels. Furthermore, smoking effect on lipid profiles remain after cessation. These data provide further justification for smoking cessation.

1 September 2015 in Atherosclerosis
Verified
Journal Article
Closed access
PHPowen Hsu
Powen Hsu
MAMasumi Ai
Masumi Ai
EKEiichiro Kanda
Eiichiro Kanda
NYNeng-Chun Yu
Neng-Chun Yu
HCHsiao-Lien Chen
Hsiao-Lien Chen
MYMasayuki Yoshida
Masayuki Yoshida

1 October 2019 in Journal of Atherosclerosis and Thrombosis
Verified
Journal Article
Open access
PDF file
HHHung Hsu
Hung Hsu
PHPowen Hsu
Powen Hsu
MCMing-Hui Cheng
Ming-Hui Cheng
YIYasuki Ito
Yasuki Ito
EKEiichiro Kanda
Eiichiro Kanda
MAMasumi Ai
Masumi Ai
Aims: Prediabetes and diabetes are associated with increased insulin resistance and decreased insulin production, dyslipidemia, and increased cardiovascular disease (CVD) risk. Our goals were to assess lipoprotein subfractions using novel assays in such subjects.Methods: Fasting normal, prediabetic, and diabetic Taiwanese men and women (n=2,049) had their serum glucose, glycosylated hemoglobin, insulin, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), HDL3-C, apolipoprotein E-HDL-C, direct low-density lipoprotein cholesterol (LDL-C), small dense LDL-C (sdLDL-C), LDL-TG, and remnant lipoprotein cholesterol (RLP-C) levels measured using novel assays. HDL2-C, LDL-C, and large-buoyant LDL-C (lbLDL-C) were calculated.Results: Prediabetic male and female subjects had significantly higher levels of TG, RLP-C, sdLDL-C, the sdLDL-C/LDL-C ratio, and LDL-TG than normal subjects, and statin treatment abolished this effect in men, but not in women. Diabetic male and female subjects had significantly higher TG and sdLDL-C/LDL-C ratios, and significantly lower levels of HDL-C, HDL2-C, HDL3-C, and apoE HDL-C than normal subjects, as did prediabetic women. Median direct LDL-C levels were >100 mg/dL in all groups, even in those receiving statin therapy. Calculated LDL-C significantly underestimated direct LDL-C by >10% in diabetic subjects.Conclusions: Our data indicate that prediabetic subjects were more likely to have significantly elevated RLP-C, sdLDL-C, and LDL-TG, while diabetic subjects were more likely to have significantly decreased HDL-C, HDL2-C, HDL3-C, and apoE HDL-C than normal subjects, and calculated LDL-C significantly underestimated their direct LDL-C. In our view, direct LDL-C and sdLDL-C should be measured and optimized in both diabetic and prediabetic subjects to reduce CVD risk.

1 December 2007 in Atherosclerosis
Verified
Journal Article
Closed access
MAMasumi Ai
Masumi Ai
ATAkira Tanaka
Akira Tanaka
KSKentaro Shoji
Kentaro Shoji
KOKyoko Ogita
Kyoko Ogita
THTadashi Hase
Tadashi Hase
KSKentaro Shimokado
Kentaro Shimokado

1 October 2023 in Journal of Atherosclerosis and Thrombosis
Verified
Journal Article
Open access
PDF file
MAMasako Arimoto
Masako Arimoto
YYYasushi Yamamoto
Yasushi Yamamoto
WIWataru Imaoka
Wataru Imaoka
TKToshio Kuroshima
Toshio Kuroshima
RTRyoko Toragai
Ryoko Toragai
MAMasumi Ai
Masumi Ai
Aims: Skipping breakfast is known as a cardiovascular disease (CVD) risk. Recently, eating and dietary patterns have been varied in many countries, however, the mechanisms of promoting CVD are still unclear. Our goal was to assess the effects of eating and dietary patterns on CVD risk factors, with a focus on lipid parameters including serum concentration of small dense low-density lipoprotein cholesterol (sdLDL-C). Methods: Subjects consisted of 27,997 Japanese men and women, who had medical check-up. Lipid parameters including sdLDL-C levels in breakfast skippers were compared with those in breakfast eaters. Lipid parameters in staple foods skippers were also compared with those in staple foods eaters. Results: Breakfast skippers had significantly (p<0.01) higher serum levels of median sdLDL-C than breakfast eaters in both genders (34.7 versus 32.0 mg/dL in men, 25.4 versus 24.9 mg/dL in women, respectively), and the same was true for sdLDL-C/LDL-C ratio (0.276 versus 0.260 in men, 0.218 versus 0.209 in women, respectively). Similarly, staple foods skippers had significantly higher sdLDL-C level than staple foods eaters in both genders (34.1 versus 31.6 mg/dL in men, 25.8 versus 24.7 mg/dL in women), and the same went for sdLDL-C/LDL-C ratio (0.278 versus 0.256 in men, 0.215 versus 0.208 mg/dL in women, respectively). Conclusion: Our data indicate that both skipping breakfast and having meals without staple foods increase serum sdLDL-C concentration and cause unfavorable lipid profiles, and then may promote CVD. These finding provide evidence for the importance of having breakfast and meals with staple foods for preventing CVD.

31 January 2008 in Clinica Chimica Acta
Verified
Journal Article
Closed access
KOKyoko Ogita
Kyoko Ogita
MAMasumi Ai
Masumi Ai
ATAkira Tanaka
Akira Tanaka
YIYasuki Ito
Yasuki Ito
THTsutomu Hirano
Tsutomu Hirano
KSKentaro Shimokado
Kentaro Shimokado