TY - JOUR
T1 - Stability of frozen serum levels of insulin-like growth factor-I, insulin-like growth factor-II, insulin-like growth factor binding protien-3, transforming growth factor β, soluble fas, and superoxide dismutase activity for the JACC Study
AU - Ito, Yoshinori
AU - Nakachi, Kei
AU - Imai, Kazue
AU - Hashimoto, Shuji
AU - Watanabe, Yoshiyuki
AU - Inaba, Yutaka
AU - Tamakoshi, Akiko
AU - Yoshimura, Takesumi
AU - Mori, Mitsuru
AU - Motohashi, Yutaka
AU - Tsuji, Ichiro
AU - Nakamura, Yosikazu
AU - Iso, Hiroyasu
AU - Mikami, Haruo
AU - Inaba, Yutaka
AU - Hoshiyama, Yoshiharu
AU - Suzuki, Hiroshi
AU - Shimizu, Hiroyuki
AU - Toyoshima, Hideaki
AU - Tokudome, Shinkan
AU - Kikuchi, Shogo
AU - Koizumi, Akio
AU - Kawamura, Takashi
AU - Miki, Tsuneharu
AU - Date, Chigusa
AU - Sakata, Kiyomi
AU - Nose, Takayuki
AU - Hayakawa, Norihiko
AU - Shibata, Akira
AU - Okamoto, Naoyuki
AU - Shio, Hideo
AU - Ohno, Yoshiyuki
AU - Kitagawa, Tomoyuki
AU - Kuroki, Toshio
AU - Tajima, Kazuo
PY - 2005
Y1 - 2005
N2 - Background: Subjects of the Japan Collaborate Cohort Study (JACC Study) gave peripheral blood samples collected between 1988 and 1990. We conducted to investigate whether levels of serum components measured after 9 years of frozen storage are stable or not. Methods: To assess the degradation of frozen serum components in the JACC Study, we compared levels of various components (IGF-I, IGF-II, IGFBP-3, TGF-β1, sFas, and total SOD activity) between fresh and stored sera collected from other inhabitants. Serum levels of constituents were measured by immunoradiometric assay (IGF-I, IGF-II and IGFBP-3), quantitative enzyme immunciassay (TGF-β1), enzyme-linked immuno-adsorbent assay (sFas), and an improved nitrite method (SOD activity). Results: The coefficients of variation for intra- and inter-assay precisions of the measurements were less than 9%. Levels of IGF-I, IGF-11, IGFBP-3, TGF-β1 and sFas in sera after storage for 9 years at - 80°C were similar to those of fresh sera newly collected from inhabitants. The distributions of serum IGF-I, IGF-II, IGFBP-3, TGF-β1, sFas and SOD activity for specimens collected from different individuals tended to be similar to those of serum levels for frozen specimens collected from different individuals and stored for 9 years. Conclusions: There was no statistically significant difference in distribution of measured values of IGF-I, IGF-II, IGFBP-3, TGF-β1, and sFas between newly collected sera and frozen specimens stored for 9 years. Thus, measurements of these serum constituents of specimens stored for the JACC Study can be reliably used in nested case-control study.
AB - Background: Subjects of the Japan Collaborate Cohort Study (JACC Study) gave peripheral blood samples collected between 1988 and 1990. We conducted to investigate whether levels of serum components measured after 9 years of frozen storage are stable or not. Methods: To assess the degradation of frozen serum components in the JACC Study, we compared levels of various components (IGF-I, IGF-II, IGFBP-3, TGF-β1, sFas, and total SOD activity) between fresh and stored sera collected from other inhabitants. Serum levels of constituents were measured by immunoradiometric assay (IGF-I, IGF-II and IGFBP-3), quantitative enzyme immunciassay (TGF-β1), enzyme-linked immuno-adsorbent assay (sFas), and an improved nitrite method (SOD activity). Results: The coefficients of variation for intra- and inter-assay precisions of the measurements were less than 9%. Levels of IGF-I, IGF-11, IGFBP-3, TGF-β1 and sFas in sera after storage for 9 years at - 80°C were similar to those of fresh sera newly collected from inhabitants. The distributions of serum IGF-I, IGF-II, IGFBP-3, TGF-β1, sFas and SOD activity for specimens collected from different individuals tended to be similar to those of serum levels for frozen specimens collected from different individuals and stored for 9 years. Conclusions: There was no statistically significant difference in distribution of measured values of IGF-I, IGF-II, IGFBP-3, TGF-β1, and sFas between newly collected sera and frozen specimens stored for 9 years. Thus, measurements of these serum constituents of specimens stored for the JACC Study can be reliably used in nested case-control study.
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U2 - 10.2188/jea.15.S67
DO - 10.2188/jea.15.S67
M3 - Article
C2 - 15881197
AN - SCOPUS:19444366925
SN - 0917-5040
VL - 15
SP - S67-S73
JO - Journal of Epidemiology
JF - Journal of Epidemiology
IS - SUPPL. 1
ER -