研究者詳細 - 大久保　真樹

論文 - 大久保　真樹

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山川智子, 大久保真樹, 羽柴正夫, 中田力, 伊藤壽助

日磁医誌 20 ( 2 ) 80 - 92 2000年4月

A comparative study of simple methods to quantify cerebral blood flow with acetazolamide challenge by using iodine-123-IMP SPECT with one-point arterial sampling 査読

M Ohkubo, Odano, I

ANNALS OF NUCLEAR MEDICINE 14 ( 2 ) 115 - 120 2000年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：JAPANESE SOCIETY NUCLEAR MEDICINE

The aim of this study was to compare the accuracy of simplified methods for quantifying rCBF with acetazolamide challenge by using I-123-N-isopropyl-p-iodoamphetamine (IMP) and SPECT with one-point arterial sampling. After acetazolamide administration we quantified rCBF in 12 subjects by the following three methods: (a) the modified microsphere method, (b) the IMP-autoradiographic (ARG) method based on a two-compartment one-parameter model, and (c) the simplified method based on a two-compartment two-parameter model (functional IMP method). The accuracy of these methods was validated by comparing rCBF values with those obtained by the standard method: the super-early microsphere method with continuous withdrawal of arterial blood. On analyzing rCBF in each flow range (0-0.25, 0.25-0.5, 0.5-0.75 and more than 0.75 ml/g/min), rCBF values obtained by both methods (a) and (c) showed significant correlations (p < 0.01) with those obtained by the standard method in every range, but rCBF values obtained by method (b) did not significantly correlated in the high flow range (0.5-0.75 and more than 0.75 ml/g/min). Method (c) was found to be the most accurate, even though it needs two serial SPECT scans. When requiring one SPECT scan, method (a) was considered to be superior to method (b) because of its accuracy, especially in high flow regions loaded with acetazolamide.

DOI： 10.1007/BF02988590

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Noninvasive quantification of cerebral blood flow using Tc-99m-ECD and SPECT 査読

Odano, I, M Ohkubo, T Yokoi

JOURNAL OF NUCLEAR MEDICINE 40 ( 10 ) 1737 - 1744 1999年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SOC NUCLEAR MEDICINE INC

The aim of this study was to develop a simple, noninvasive method for quantifying regional cerebral blood flow (rCBF) using Tc-99m-ethyl cysteinate dimer (ECD) by a single SPECT scan and single venous sampling. Methods: Using a three-compartment model, we introduced the regional brain fractionation index (BF!); Cb(T-s)/integral(0)(Ts) Ca(tau)d tau[Ca(t), arterial input; Cb(t), brain activity]. Regional BFI obtained at the optimum time T-s (min) was converted to rCBF using an exponential function, which was obtained by analyzing the relationship between regional BFI and rCBF (= F) obtained by the standard Xe-133 inhalation SPECT method. The integral of the concentration of Tc-99m-ECD in arterial blood corrected for physical decay [Ca(t)] in BFI was estimated from a single venous blood sample obtained at the optimum time T-v using the regression line obtained by analyzing the relationship between the integral of Ca(t) and venous sample data. The data come from three groups of patients. The first group of patients (n = 16) underwent a complete Tc-99m-ECD BFI study with measurement of Ca(t) and dynamic SPECT scanning, as well as a Xe-133 inhalation study to measure rCBF. The results were used to analyze the relationship between regional BFI and rCBF (obtained with Xe-133) and to determine the optimum time T-s for obtaining BFI. Data from the second group of patients (n = 15) were used to analyze the relationship between the integral of Ga(t) and venous sample data and to determine the optimum time T-v for one-point Venous blood sampling. Finally, the third group of patients (8 patients, 10 studies) was used to validate the current method by comparing the results with Xe-133 inhalation SPECT. Results: Regional BFI obtained at time T-s = 20 min showed good agreement (r = 0.907; a = 0.552, b = 0.962) with rCBF. The venous sample data obtained at time T-v = 6 min showed a good correlation (r = 0.988) with BFI. In comparing rCBF Values thus obtained and those obtained by the Xe-133 method, we found a good correlation (r = 0.917, slope = 1.01). Conclusion: The proposed method has three advantages: (a) accurate quantification of rCBF without underestimation in the high flow range, (b) simplicity and noninvasiveness and (c) the ability to use any type of SPECT camera for the study.

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Quantification of cerebral blood flow using technetium-99m ethyl cysteinate dimer and single-photon emission tomography 査読

Odano, I, M Ohkubo

EUROPEAN JOURNAL OF NUCLEAR MEDICINE 26 ( 3 ) 246 - 252 1999年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SPRINGER VERLAG

The aim of this study was to develop a new method for quantifying regional cerebral blood flow (rCBF) with technetium-99m ethyl cysteinate dimer (ECD) and single-photon emission tomography (SPET). Employing a three-compartment model, we introduced a parameter, regional brain fractionation index (BFI), that reflects rCBF values and is obtained by a single SPET scan at optimum time T (min) after tracer injection and the integral of arterial input. By analysing the dynamic SPET and arterial blood sampling data of 15 subjects, including the results of acetazolamide challenges, with the graphical plot method, optimum time T was determined to be approximately 20 min post injection. Regional BFI values of each subject were calculated from the single SPET data at 20 min and arterial input. The relationship between the values of regional BFI and rCBF obtained by xenon-133 inhalation SPET was analysed by approximation with an exponential function, resulting in good agreement (r = 0.907). In the present method, I CBF values were determined from regional BFI values by using the inverse exponential function as a non-linear regression curve. To validate the method, we applied it to six other subjects, in whom acetazolamide challenges were also performed. In comparing rCBF values thus obtained and those obtained by Xe-133 inhalation SPET, we found a good correlation (r = 0.901) with an inclination approximating 1 (= 1.02) and without underestimation of rCBF in the high-flow range. Since the present method does not require dynamic planar imaging or dynamic SPET scanning, it can be applied to any type of SPET scanner and is useful in clinical SPET studies.

DOI： 10.1007/s002590050384

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Diamox負荷時における123I-IMP SPECTを用いたマイクロスフェアモデルに基づく局所脳血流量定量法の精度の検討査読

大久保真樹, 小田野行男, 野口栄吉, 大滝広雄, 柴木充朗, 土橋幸夫, 横井孝司

核医学 35 ( 3 ) 147 - 151 1998年3月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：(一社)日本核医学会

検討した定量法は,N-isopropyl-p-[123I]iodoamphetamine(IMP)静注5分後のSPECT撮像と持続動脈採血を行う超早期マイクロスフェア法と,静注30分後のSPECT撮像と1点動脈採血を行う早期マイクロスフェア法である.5名の被検者において,Diamox投与10分後にIMPを静注し直後からダイナミックSPECT撮像と頻回動脈採血を行い,2コンパートメントモデル解析によって局所脳血流(rCBF)を算出した.超早期マイクロスフェア法と早期マイクロスフェア法で求めたrCBFは,いずれも2コンパートメントモデル解析による値と高い相関を示し(r=0.982,0.930),偏りは殆どみられなかった.マイクロスフェアモデルに基づく定量法は,安静時のみならずDiamox負荷時においても適用可能であることが確認された.特に,1点採血法による早期マイクロスフェア法は侵襲性が低く簡便で,より臨床に適する方法と考えられる

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分割投与99mTc-ECD SPECTと静脈採血によるDiamox負荷前後の脳血流測定法査読

小田野行男, 大久保真樹, 野口栄吉, 大滝広雄, 柴木充朗, 土橋幸夫

核医学 35 ( 2 ) 74 - 75 1998年

99mTc-ECD SPECTを用いた3-コンパートメントモデルに基づく脳血流測定法査読

小田野行男, 大久保真樹, 野口栄吉, 大滝広雄, 柴木充朗, 土橋幸夫

核医学 35 ( 8 ) 702 - 703 1998年

細胞動態からみた薬剤併用放射線照射における細胞致死効果査読

藤田勝三, 大久保真樹, 日向浩, 酒井邦夫, 伊藤猛, 末山博男

関越UFT研究会 10 7 - 10 1997年12月

FM3A細胞における5-FU+CDDPの放射線増感効果の細胞動態学的検討査読

藤田勝三, 大久保真樹, 日向浩, 酒井邦夫

新大医短紀要 6 ( 2 ) 229 - 232 1997年12月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：新潟大学医療技術短期大学部

対数増殖期のFM3A細胞に対して5-FU 0.5μg/mlとcisplatin(CDDP)0.1μg/mlの24時間同時処理を行った.薬剤処理開始30分後に37℃恒温槽中で60Coγ線を2Gy照射した.薬剤除去直後,24,48,72時間後に細胞DNAをPI染色し,FACScanにより細胞動態解析を行った.FM3A細胞は2剤同時処理と2Gy併用により,薬剤除去72時間後に著明なG2ブロックが認められた.長時間G2ブロックされた細胞の多くは巨大細胞,多核細胞となりやがて死滅する.FM3A細胞における,(5-FU+CDDP)2剤同時処理による放射線増感効果は,コロニー法による細胞生存曲線と共に細胞動態の面からも支持される

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99mTc-ECD SPECTを用いたマイクロスフェアーモデルに基づく非侵襲的な脳血流測定1点動脈または静脈採血法査読

小田野行男, 大久保真樹, 野口栄吉, 大滝広雄, 柴木充朗, 土橋幸夫

核医学 34 ( 12 ) 1111 - 1117 1997年12月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：(一社)日本核医学会

1点採血法と99mTc-ECD SPECTを用いる本法は,頭部や大動脈等のdynamic測定が不要であり,1回のSPECT撮像と1回の動脈ないし静脈採血データから脳血流を簡便に精度よく定量測定できる有用な検査法である

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I-123 IMP SPECTによる簡便なrCBF定量測定法の臨床応用，招待査読

大久保真樹, 小田野行男, 野口栄吉, 大滝広雄, 柴木充朗, 土橋幸夫

映像情報メディカル 29 ( 22 ) 1330 - 1333 1997年11月

Quantification of cerebral blood flow and partition coefficient using iodine-123-iodoamphetamine 査読

Odano, I, M Ohkubo, M Takahashi

JOURNAL OF NUCLEAR MEDICINE 38 ( 8 ) 1248 - 1253 1997年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SOC NUCLEAR MEDICINE INC

The aim of this study was to develop a simple, noninvasive method for quantifying both regional cerebral blood flow (rCBF) and the partition coefficient (lambda) using N-isopropyl-p-[I-123]iodoamphetamine and SPECT. Methods: By employing a two-compartment model (influx, K-1; outflux, k(2)), a new method was introduced that requires two serial SPECT scans at 30 min and 60 min, and a single arterial sample 5 min after tracer injection. The integral of the arterial input function is inferred from the sample by using the correlation obtained from 25 subjects. Two original mathematical functions, Phi for K-1 and Gamma for h (= K-1/k(2)), were obtained from the input functions of 12 subjects. The values of K-1 and lambda are determined from the two scans and the single arterial sample by using these functions. The values obtained for K-1 (= rCBF) and lambda weve compared with those obtained by nonlinear least-squares fitting analysis and the Xe-133 inhalation SPECT method, Results: K-1 and lambda were in good agreement with the values obtained by nonlinear least-squares fitting analysis (r = 0.873 in K-1 and r = 0.825 in lambda), and rCBF values were closely correlated with those obtained by the Xe-133 method (r = 0.843). Conclusion: The proposed method has three advantages: (a) accurate, simultaneous quantification of both rCBF and the partition coefficient; (b) simplicity and noninvasiveness; and (c) a relatively short period (approximately 70 min) for the study.

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99mTc-ECD SPECTにおける2分割投与法(split-dose法)の問題点と改良法査読

小田野行男, 大久保真樹, 高橋誠

核医学 34 ( 5 ) 323 - 328 1997年5月

記述言語：日本語出版者・発行元：(一社)日本核医学会

2分割投与99mTc-ECD脳血流SPECTにおいて,投与比によりSPECTカウントを補正する方法の妥当性を検討した.何らかの負荷を加えた場合に有意な脳血流の変化を検出するためには,安静時SPECTカウントの約20%以上の変化が必要であると考えられた.したがって脳血流の増減が少ない負荷検査において,脳血流の変化を投与比補正法で評価することは困難であると思われた.また,投与比による補正法を用いない方法を考案した.この方法では2回のSPECTカウントを脳内のある参照領域で規格化し,その変化率で脳血流の増減を評価する.本法は,投与比補正法が有する問題点の影響を受けないので,起立負荷や手指運動負荷などの負荷検査には有用と考えられた

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A comparative study of simple methods to measure regional cerebral blood flow using iodine-123-IMP SPECT 査読

M Ohkubo, Odano, I, M Takahashi

JOURNAL OF NUCLEAR MEDICINE 38 ( 4 ) 597 - 601 1997年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SOC NUCLEAR MEDICINE INC

The aim of this study was to compare the accuracy and reliability of simple methods of quantifying regional cerebral blood Row (rCBF) with I-123-labeled N-isopropyl-p-iodoamphetamine (IMP) and SPECT and to determine which method was best. Methods: Four methods were examined: (a) the microsphere method with continuous withdrawal of arterial blood, which was based on a microsphere model using the SPECT image obtained 5 min after tracer injection, (b) the microsphere method with one-point sampling, which was the same as the first method except that one-point sampling was used instead of continuous withdrawal, (c) the modified microsphere method with one-point sampling, which was the same as the second method except that a later SPECT image (30-min postinjection) with correction was used and (d) a table look-up method based on a two-compartment model with one-point arterial blood sampling and two SPECT scans obtained 40- and 180-min postinjection. The accuracy of these methods was validated by comparing the rCBF values with those obtained by nonlinear least squares fitting analysis based on the two-compartment model in 15 subjects. Results: Regional cerebral blood flow values obtained by the first method correlated most closely with those obtained by nonlinear least squares fitting analysis (error, 6.8%). The second method estimated rCBF with a mean error of 10.4%. The third method estimated rCBF with a mean error of 13.1%, even though it tended to slightly overestimate rCBF. The fourth method was inclined to underestimate rCBF with a mean error of 17.1%, and it greatly overestimated regional distribution volume. Conclusion: The first method was the most accurate and reliable. For less invasiveness, the first method should be combined with one-point sampling instead of continuous withdrawal, which was used in the second method. When using a delayed SPECT image with a conventional SPECT scanner, the third method was considered to be superior to the fourth method.

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123I-IMP,99mTc-HMPAO及び99mTc-ECDによる脳血流SPECT画像の比較検討査読

小田野行男, 大久保真樹, 高橋誠

核医学 34 ( 3 ) 189 - 194 1997年3月

記述言語：日本語出版者・発行元：(一社)日本核医学会

変性疾患や脳梗塞など7例を対象に,同一の時期に3種のトレーサによるSPECT検査を施行した.領域/大脳比(Uptake ratio)の変動係数は,HMPAO補正(+)>IMP>ECD>HMPAO補正(-)の順で低くなり,画像のコントラストはHMPAO補正(+)が最もよく,HMPAO補正(-)が最も不良であった.HMPAOは画像コントラストを改善するためにLassen補正を行うべきと考えた.Uptake ratioは,脳幹,視床,後頭葉及び白質で有意差が見られた.ECDのUptake ratioはIMPに比較して脳幹,視床で有意な低値となり,HMPAO(補正(+))のそれは脳幹で有意に低値であった.IMPに比較して,ECD及びHMPAO(補正(-))のUptake ratioは後頭葉で有意な高値を示した.脊髄小脳変性症など脳幹病変の有無が問題となる場合には,ECD及びHMPAOには問題があり,IMPを使用するのがよいと思われた

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FM3A細胞に対する５-FU＋CDDPの放射線増感効果－細胞増殖と色素排除能による解析－査読

藤田勝三, 酒井邦夫, 樋口正一, 末山博男, 大久保真樹

新潟大学医療技術短期大学部紀要 6 ( 1 ) 103 - 108 1997年2月

学生用計測機器操作支援システム査読

中村久吾, 大久保真樹

新潟大学医療技術短期大学部紀要 6 ( 1 ) 123 - 128 1997年2月

125I-iomazenil binding shows stress- and/or diazepam-induced reductions in mouse brain: Supporting data for 123I-iomazenil SPECT study of anxiety disorders 査読

Makoto Takahashi, Ikuo Odano, Shozo Fujita, Masaki Ohkubo

Annals of Nuclear Medicine 11 ( 3 ) 243 - 250 1997年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Springer Tokyo

Effects of repeated swim stress on the binding of 125I-iomazenil were examined in the brains of diazepam-treated and non-treated mice. The mice were orally administered diazepam or vehicle (0.5% ethylene glycol) and subjected to daily swim stress (at 20°C for 10 min) for seven consecutive days. The distribution and the amount of 125I-iomazenil binding were analyzed autoradiographically after in vivo and in vitro binding experiments. Repeated swim stress decreased the in vivo binding in the hippocampus (p &lt
0.05) and cerebral cortex (p &lt
0.05) of vehicle-treated mice but caused no significant changes in diazepam-treated mice. Subchronic treatment with diazepam decreased the in vivo binding approximately 50% in all brain regions examined (p &lt
0.01). The in vitro experiment, however, revealed no significant changes except in the hippocampus, where a small but significant decrease in the binding was observed after subchronic treatment with diazepam (p &lt
0.01). The stress- or diazepam-induced reductions seem to represent alterations in the in vivo environment related to 125I-iomazenil binding. These results suggest that we can investigate the pathophysiology of stress and anxiety with 123I-iomazenil SPECT. Care must be taken concerning the effects of benzodiazepines.

DOI： 10.1007/BF03164770

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FM-3A細胞に対する５-FU＋CDDPの放射線増感効果査読

藤田勝三, 樋口正一, 末山博男, 酒井邦夫, 大久保真樹

関越UFT研究会 9 21 - 24 1996年12月

Elevation of cerebral lactate detected by localized H-1-magnetic resonance spectroscopy in migraine during the interictal period 査読

H Wantanabe, T Kuwabara, M Ohkubo, S Tsuji, T Yuasa

NEUROLOGY 47 ( 4 ) 1093 - 1095 1996年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：LITTLE BROWN CO

We used localized H-1-magnetic resonance spectroscopy (MRS) to study the metabolic changes in the brains of patients with migraine during the interictal period. Measurement of metabolite levels in the occipital visual cortex in six normal subjects and six patients disclosed high lactate levels in the five patients who had experienced a migraine attack within the previous 2 months. One patient who had not experienced a migraine attack in the previous 4 years did not show a lactate peak. We speculate that anaerobic glycolysis occurs in the brains of patients with migraine during the interictal period, and a long attack-free period may normalize the subclinical metabolic disturbance.

DOI： 10.1212/WNL.47.4.1093

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論文 - 大久保 真樹

<大久保　真樹>

論文 - 大久保　真樹