Masao Miyagawa - Academia.edu (original) (raw)
Papers by Masao Miyagawa
Japanese Circulation Journal-english Edition, 1994
Recently, remarkable progress in cardiac imaging with FDG PET and MRI has been made. FDG PET dete... more Recently, remarkable progress in cardiac imaging with FDG PET and MRI has been made. FDG PET detects active inflammatory lesions in cardiac sarcoidosis (CS) as hot spots with a better sensitivity than 67Ga scintigraphy. The new guidelines for diagnosis and treatment of CS were published by the Heart Rhythm Society in 2014, and more recently revised by the Japanese Circulation Society in 2017. In the past few years, many studies have demonstrated the diagnostic utility of FDG PET in patients with CS; therefore, abnormally high FDG accumulation in the heart was adopted as the major criteria for cardiac involvement of sarcoidosis. At present, FDG PET/CT is considered mandatory in the clinical diagnosis group of the updated guidelines.
IJC Heart & Vasculature, 2020
Background: Sarcoidosis is a systemic inflammatory disorder and can often affect any other organs... more Background: Sarcoidosis is a systemic inflammatory disorder and can often affect any other organs beyond the heart. Whole-body 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) is used to detect not only cardiac but also extra-cardiac involvement of sarcoidosis. However, the features and clinical impact of extra-cardiac lesions have not yet been fully elucidated. Therefore, this study aimed to clarify these using FDG-PET. Methods and results: We enrolled 120 consecutive patients with abnormal findings clinically suggesting cardiac sarcoidosis who underwent whole-body FDG-PET. In this study, a patient with suspected cardiac sarcoidosis was defined as one having both clinically suspected findings and FDG-PET positive cardiac uptake. Subsequently, a total of 36 patients with suspected cardiac sarcoidosis were found and analyzed. Extra-cardiac involvement was detected in 35 lesions of 14 patients (39% per patient). In particular, the extra-cardiac lesions were widely distributed throughout the body, and mediastinal/hilar lymph node involvement was most commonly observed. In most of the patients (93% per patient, 13/14), the extra-cardiac lesions were localized in the regions that were considered more accessible with less risk of complication compared with endomyocardial biopsy (EMB). Based on the FDG-PET findings, 8 patients underwent extra-cardiac biopsy without complication, and its diagnostic sensitivity for histological sarcoidosis was high (75%, 6/8). Moreover, FDG-PET-guided extra-cardiac biopsy could confirm histological sarcoidosis in 4 lesions that EMB failed to prove. Conclusions: Extra-cardiac involvement in patients with suspected cardiac sarcoidosis was relatively high. FDG-PET-guided extra-cardiac biopsy may be safe and useful for the imaging based diagnosis of cardiac sarcoidosis.
International Journal of Clinical Oncology, 2020
Background To evaluate the treatment outcomes of external-beam radiotherapy (EBRT) with or withou... more Background To evaluate the treatment outcomes of external-beam radiotherapy (EBRT) with or without radioactive iodine therapy (RAIT) for metastatic or recurrent lesions of differentiated thyroid cancer (DTC). Methods Between August 1997 and March 2018, 73 lesions (distant metastases, 50; regional lymph-node metastases, 17; postoperative tumor-bed recurrences, 6) in 36 patients that had received EBRT with or without RAIT were reviewed. Doses of EBRT were 8-70 Gy (median 40 Gy). Seventeen patients received RAIT after EBRT. Results Median follow-up time of imaging studies was 14 months (range 1-110 months). Two-year overall survival rates and control rates of EBRT sites were 71% and 62%, respectively. Two-year control rates for EBRT of < 30 Gy (n = 7), 30 Gy (n = 13), 31-49 Gy (n = 25), 50 Gy (n = 20), and > 50 Gy (n = 8) were 0%, 56%, 53%, 79%, and 100%, respectively. There were statistically significant differences in control rates between < 30 Gy and 30 Gy (p = 0.003), and between 50 Gy and > 50 Gy (p = 0.037). Control rates of > 50 Gy were significantly better compared to ≤ 50 Gy (p = 0.021). Two-year control rates with (n = 28) and without (n = 45) post-EBRT RAIT were 89% and 45%, respectively (p = 0.009). In multivariate analysis, EBRT of > 50 Gy and post-EBRT RAIT were significant independent factors for favorable control of EBRT sites (hazard ratio [HR], 5.72; 95% confidence interval [CI], 1.21-27.1; p = 0.028 and HR, 2.98; 95% CI, 1.28-6.98; p = 0.012, respectively). Conclusion EBRT of > 50 Gy and post-EBRT RAIT appeared to be useful for long-term control of EBRT sites for metastatic or recurrent lesions of DTC.
Radiotherapy and Oncology, 2019
Image-guided radiotherapy has revealed the dynamic nature of patients who can unexpectedly exhibi... more Image-guided radiotherapy has revealed the dynamic nature of patients who can unexpectedly exhibit positioning variations, substantial organ motion and deformation, weight loss and tumour responses. This
The Japanese Journal of Sarcoidosis and Other Granulomatous Disorders, 2015
The Journal of Urology, 2015
INTRODUCTION AND OBJECTIVES: Fluorodeoxygulcose positron emission tomography/computed tomography ... more INTRODUCTION AND OBJECTIVES: Fluorodeoxygulcose positron emission tomography/computed tomography (FDG-PET/CT) is becoming useful for diagnosis, staging and prognosis in many cancers. In contrary, the use in urological oncology has been slower to develop because the radiotracer is excreted into the urine. Then, to assess the ability of preoperative FDG-PET/CT to detect upper urinary tract cancers (UUTC), compared with pathological examinations of tissues obtained by ureteroscopic biopsy or split cytologic analysis of urines obtained following retrograde pyelography. METHODS: Clinicopathological records of patients who were examined by FDG-PET/CT were retrospectively reviewed. Sixty-four patients (66 lesions) with clinically suspected UUTC, who were diagnosed by ureteroscopy or nephroureterectomy or partial ureterectomy at our institution from September 2010 to September 2014, were included. The patient cohort consisted of 51 men and 13 women, with a median age of 73 (range 54e92) years. RESULTS: 66 lesions were histologically diagnosed as 59 urothelial carcinomas and 1 clear cell carcinoma and 6 benign lesions. Only 22% of 58 lesions with UUTC had positive voided urine cytology and 45% of 47 lesions had positive split urine cytology. In addition, only 53 % of 15 lesions with UUTC had positive endoscopic biopsy. However, 83% of 60 lesions with UUTC had positive FDG-PET/CT examination. The positive predictive value was 93%. The sensitivities of <pT2 and pT2 were 82% and 83%, respectively, and the sensitivities of G1, G2, and G3 tumors were 100%, 86%, and 82%, respectively. There were no correlations between the sensitivity in FDG-PET/CT and tumor stage or tumor grade. Mean SUVmax was 3.0 and 10.0 in benign lesions and UUTC, respectively. The difference was statistically significant (p1⁄40.027). The ROC analysis showed that a SUVmax cut-off value to discriminate UUTC was 5.6. The sensitivity and the specificity were 76% and 80%, respectively. An area under the curve was 0.800 (Fig). CONCLUSIONS: FDG-PET/CT was effective to detect UUTC. Furthermore, SUVmax had a role of supplementary index. FDG-PET/ CT may be able to replace of endoscopic biopsy depending on the patients. Source of Funding: none
Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1997
We examined whether 201Tl myocardial scintigraphy with intravenous infusion of adenosine triphosp... more We examined whether 201Tl myocardial scintigraphy with intravenous infusion of adenosine triphosphate (ATP) can be substituted for dipyridamole (DIP) in the diagnosis of coronary artery disease CAD). The coronary flow reserve (CFR) during intravenous infusion of ATP (0.10-0.20 mg/kg/min) was compared with that during intravenous infusion of DIP (0.56 mg/kg) using a Doppler flow wire in 19 subjects with normal coronary arteries. The highest CFR level was found in the ATP dose range of 0.16-0.20 mg/kg/min. The CFR at the ATP dose of 0.16 mg/kg/min was significantly higher than that during DIP infusion (4.2 versus 3.6) (p < 0.01), for which reason we adopted this dose of ATP. According, 201Tl SPECT in 140 patients with suspected CAD was performed after infusion of 0.16 mg/kg/min of ATP in 70 of them and 0.56 mg/kg of DIP in the 70 others. ATP stress 201Tl SPECT showed no significant difference in sensitivity and accuracy from DIP stress 201Tl SPECT (87.0% versus 82.9, and 87.1% vers...
Kaku igaku. The Japanese journal of nuclear medicine, 1991
Journal of the American College of Cardiology, 2004
We sought to evaluate the time course of insulin-stimulated myocardial glucose uptake (MGU) in mi... more We sought to evaluate the time course of insulin-stimulated myocardial glucose uptake (MGU) in mice that had undergone ablation of glucose transporter-4 (GLUT4). BACKGROUND The relative importance of GLUT4, the most abundant insulin-responsive glucose transporter, to modulate myocardial glucose metabolism is not well defined. METHODS Myocardial glucose uptake was assessed at various time points after glucose (1 mg/g) and insulin (8 mU/g) injection in GLUT4-null (G4N) (n ϭ 48) and wild-type (WT) (n ϭ 48) mice with 18 F-2-deoxy-2-fluoro-D-glucose (FDG) using in vivo positron emission tomography (PET), in vitro gamma-counter biodistribution, and isolated, perfused hearts. RESULTS Baseline assessment with PET imaging showed comparable MGU in G4N (0.66 Ϯ 0.12) and WT (0.67 Ϯ 0.11, p ϭ 0.70) mice. Early after insulin injection, WT mice demonstrated a 3.5-fold increase in MGU (2.45 Ϯ 0.45, p ϭ 0.03), whereas G4N mice presented no increase (1.11 Ϯ 0.24, p ϭ 0.28). At 60 min, MGU was comparable in G4N (3.19 Ϯ 0.60) and WT (2.66 Ϯ 0.47, p ϭ 0.28) mice. In vitro gamma-counter biodistribution evaluation confirmed in G4N mice a lack of MGU increase early after insulin, but a slow response over 120 min. The isolated, perfused hearts of G4N mice during short-term (15 min) insulin stimulation displayed no increase in MGU (0.08 Ϯ 0.01 ml/g/min), whereas WT mice presented a threefold increase (0.22 Ϯ 0.01 ml/g/min, p Ͻ 0.01). With long-term (60 min) insulin stimulation, similar MGU was found in G4N (0.31 Ϯ 0.02 ml/g/min) and WT (0.33 Ϯ 0.04 ml/g per min, p ϭ 0.04) mice. CONCLUSIONS The G4N mice displayed an increase of MGU in response to insulin similar to that of controls, but with a markedly delayed time response. Our findings underscore the important role of GLUT4 in the rapid adaptive response of myocardial glucose metabolism.
European Journal of Nuclear Medicine, 1991
To evaluate the usefulness of myocardial scintigraphy as a monitoring tool for chronic doxorubici... more To evaluate the usefulness of myocardial scintigraphy as a monitoring tool for chronic doxorubicin (DXR) cardiotoxicity, a rat model was used to investigate the relationship between the myocardial uptake of thallium 201 (T1) or rechnetium 99m pyrophosphate (99mTc-PPi) and histological changes of the heart. Although there was no significant difference in myocardial T1 uptake between control and DXR-treated rats at an early phase after T1 injection, late-phase T1 uptake was significantly higher in the DXR-treated rats than in the control rats, indicating a slow wash-out of T1 from the myocardium. The wash-out rate calculated from scintigraphic examination of DXR-treated rats was significantly decreased with increasing degree of cardiomyopathy. Since the T1 wash-out rate was sharply decreased even in animals with minimal histological changes, it may be a possible monitoring tool for the early detection of chronic DXR cardiotoxicity. On the other hand, myocardial 99mTc-PPi images could be obtained only in rats with severe myocardial changes and hence would not useful for early detection.
Cardiovascular Research, 2005
Imaging of reporter gene expression holds promise for noninvasive monitoring of cardiovascular mo... more Imaging of reporter gene expression holds promise for noninvasive monitoring of cardiovascular molecular therapy. We investigated the feasibility of myocardial gene expression imaging in living rats using the human sodium/iodide symporter gene (hNIS) and widely available scintigraphic techniques. Methods: We injected adenovirus expressing hNIS under control of cytomegalovirus promoter (Ad hNIS) directly into left ventricular myocardium of Wistar rats. For detection of reporter gene expression, dynamic gamma-camera imaging was performed following intravenous injection of 123 Iodide or 99m Technetium. Results: For both radiotracers, focal cardiac accumulation was identified as early as 10 min, and remained detectable until 2 hrs after injection, while it was not present in animals injected with LacZ control virus. Intensity of tracer accumulation gradually decreased when decreasing titers of Ad hNIS were applied. Treatment with sodium perchlorate (a blocker of hNIS) abolished cardiac tracer uptake after Ad hNISinfection. Serial imaging after cardiac gene transfer demonstrated a peak of tracer signal between days 1 and 3, and a subsequent decrease until day 12. Postmortem analysis of hearts yielded significant correlation between in vivo radiotracer accumulation and ex vivo gammacounting. Autoradiography demonstrated specific regional radioactivity in Ad hNIS-infected myocardial areas. Conclusions: hNIS offers a practical and reliable approach for myocardial gene expression imaging. Using suitable vectors, hNIS may be coexpressed with therapeutic genes or stably expressed in stem cells for future monitoring of cardiovascular molecular therapy.
Annals of Nuclear Medicine, 2014
Annals of Hematology, 2012
The treatment of patients with diffuse large B cell lymphoma (DLBCL) would be greatly facilitated... more The treatment of patients with diffuse large B cell lymphoma (DLBCL) would be greatly facilitated with a rapid method for determining prognosis that can be performed more easily and earlier than cytological or specific pathological examinations. It has been suggested that newly diagnosed patients with DLBCL who have low maximum standard uptake value (SUV max) on 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) are more likely to be successfully treated and remain in remission compared with patients with high SUV max , but this concept has been poorly studied. We retrospectively analyzed 50 patients with de novo DLBCL to evaluate the relationship between the SUV max and disease progression. For patients with low SUV max (n010) and high SUV max (n040) (P00.255), respectively, the 3-year overall survival rates were 90 and 72 %, and the progressionfree survival (PFS) rates were 90 and 39 % (P00.012). By multivariate analysis, the revised International Prognostics Index (R-IPI) and SUV max at diagnosis were shown to predict longer PFS. The 3-year PFS for patients with low SUV max classified into the good prognosis group by R-IPI was 100 vs. 62 % for those with high SUV max (P00.161), and patients with low SUV max classified into the poor prognosis group by R-IPI was 80 vs. 18 % for those with high SUV max (P00.050). We conclude that the SUV max on FDG-PET for newly diagnosed patients with DLBCL is an important predictor of disease progression, especially for patients with poor prognosis by R-IPI.
American Journal of Roentgenology, 2002
Japanese Circulation Journal, Mar 1, 1994
Japanese Circulation Journal-english Edition, 1994
Recently, remarkable progress in cardiac imaging with FDG PET and MRI has been made. FDG PET dete... more Recently, remarkable progress in cardiac imaging with FDG PET and MRI has been made. FDG PET detects active inflammatory lesions in cardiac sarcoidosis (CS) as hot spots with a better sensitivity than 67Ga scintigraphy. The new guidelines for diagnosis and treatment of CS were published by the Heart Rhythm Society in 2014, and more recently revised by the Japanese Circulation Society in 2017. In the past few years, many studies have demonstrated the diagnostic utility of FDG PET in patients with CS; therefore, abnormally high FDG accumulation in the heart was adopted as the major criteria for cardiac involvement of sarcoidosis. At present, FDG PET/CT is considered mandatory in the clinical diagnosis group of the updated guidelines.
IJC Heart & Vasculature, 2020
Background: Sarcoidosis is a systemic inflammatory disorder and can often affect any other organs... more Background: Sarcoidosis is a systemic inflammatory disorder and can often affect any other organs beyond the heart. Whole-body 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) is used to detect not only cardiac but also extra-cardiac involvement of sarcoidosis. However, the features and clinical impact of extra-cardiac lesions have not yet been fully elucidated. Therefore, this study aimed to clarify these using FDG-PET. Methods and results: We enrolled 120 consecutive patients with abnormal findings clinically suggesting cardiac sarcoidosis who underwent whole-body FDG-PET. In this study, a patient with suspected cardiac sarcoidosis was defined as one having both clinically suspected findings and FDG-PET positive cardiac uptake. Subsequently, a total of 36 patients with suspected cardiac sarcoidosis were found and analyzed. Extra-cardiac involvement was detected in 35 lesions of 14 patients (39% per patient). In particular, the extra-cardiac lesions were widely distributed throughout the body, and mediastinal/hilar lymph node involvement was most commonly observed. In most of the patients (93% per patient, 13/14), the extra-cardiac lesions were localized in the regions that were considered more accessible with less risk of complication compared with endomyocardial biopsy (EMB). Based on the FDG-PET findings, 8 patients underwent extra-cardiac biopsy without complication, and its diagnostic sensitivity for histological sarcoidosis was high (75%, 6/8). Moreover, FDG-PET-guided extra-cardiac biopsy could confirm histological sarcoidosis in 4 lesions that EMB failed to prove. Conclusions: Extra-cardiac involvement in patients with suspected cardiac sarcoidosis was relatively high. FDG-PET-guided extra-cardiac biopsy may be safe and useful for the imaging based diagnosis of cardiac sarcoidosis.
International Journal of Clinical Oncology, 2020
Background To evaluate the treatment outcomes of external-beam radiotherapy (EBRT) with or withou... more Background To evaluate the treatment outcomes of external-beam radiotherapy (EBRT) with or without radioactive iodine therapy (RAIT) for metastatic or recurrent lesions of differentiated thyroid cancer (DTC). Methods Between August 1997 and March 2018, 73 lesions (distant metastases, 50; regional lymph-node metastases, 17; postoperative tumor-bed recurrences, 6) in 36 patients that had received EBRT with or without RAIT were reviewed. Doses of EBRT were 8-70 Gy (median 40 Gy). Seventeen patients received RAIT after EBRT. Results Median follow-up time of imaging studies was 14 months (range 1-110 months). Two-year overall survival rates and control rates of EBRT sites were 71% and 62%, respectively. Two-year control rates for EBRT of < 30 Gy (n = 7), 30 Gy (n = 13), 31-49 Gy (n = 25), 50 Gy (n = 20), and > 50 Gy (n = 8) were 0%, 56%, 53%, 79%, and 100%, respectively. There were statistically significant differences in control rates between < 30 Gy and 30 Gy (p = 0.003), and between 50 Gy and > 50 Gy (p = 0.037). Control rates of > 50 Gy were significantly better compared to ≤ 50 Gy (p = 0.021). Two-year control rates with (n = 28) and without (n = 45) post-EBRT RAIT were 89% and 45%, respectively (p = 0.009). In multivariate analysis, EBRT of > 50 Gy and post-EBRT RAIT were significant independent factors for favorable control of EBRT sites (hazard ratio [HR], 5.72; 95% confidence interval [CI], 1.21-27.1; p = 0.028 and HR, 2.98; 95% CI, 1.28-6.98; p = 0.012, respectively). Conclusion EBRT of > 50 Gy and post-EBRT RAIT appeared to be useful for long-term control of EBRT sites for metastatic or recurrent lesions of DTC.
Radiotherapy and Oncology, 2019
Image-guided radiotherapy has revealed the dynamic nature of patients who can unexpectedly exhibi... more Image-guided radiotherapy has revealed the dynamic nature of patients who can unexpectedly exhibit positioning variations, substantial organ motion and deformation, weight loss and tumour responses. This
The Japanese Journal of Sarcoidosis and Other Granulomatous Disorders, 2015
The Journal of Urology, 2015
INTRODUCTION AND OBJECTIVES: Fluorodeoxygulcose positron emission tomography/computed tomography ... more INTRODUCTION AND OBJECTIVES: Fluorodeoxygulcose positron emission tomography/computed tomography (FDG-PET/CT) is becoming useful for diagnosis, staging and prognosis in many cancers. In contrary, the use in urological oncology has been slower to develop because the radiotracer is excreted into the urine. Then, to assess the ability of preoperative FDG-PET/CT to detect upper urinary tract cancers (UUTC), compared with pathological examinations of tissues obtained by ureteroscopic biopsy or split cytologic analysis of urines obtained following retrograde pyelography. METHODS: Clinicopathological records of patients who were examined by FDG-PET/CT were retrospectively reviewed. Sixty-four patients (66 lesions) with clinically suspected UUTC, who were diagnosed by ureteroscopy or nephroureterectomy or partial ureterectomy at our institution from September 2010 to September 2014, were included. The patient cohort consisted of 51 men and 13 women, with a median age of 73 (range 54e92) years. RESULTS: 66 lesions were histologically diagnosed as 59 urothelial carcinomas and 1 clear cell carcinoma and 6 benign lesions. Only 22% of 58 lesions with UUTC had positive voided urine cytology and 45% of 47 lesions had positive split urine cytology. In addition, only 53 % of 15 lesions with UUTC had positive endoscopic biopsy. However, 83% of 60 lesions with UUTC had positive FDG-PET/CT examination. The positive predictive value was 93%. The sensitivities of <pT2 and pT2 were 82% and 83%, respectively, and the sensitivities of G1, G2, and G3 tumors were 100%, 86%, and 82%, respectively. There were no correlations between the sensitivity in FDG-PET/CT and tumor stage or tumor grade. Mean SUVmax was 3.0 and 10.0 in benign lesions and UUTC, respectively. The difference was statistically significant (p1⁄40.027). The ROC analysis showed that a SUVmax cut-off value to discriminate UUTC was 5.6. The sensitivity and the specificity were 76% and 80%, respectively. An area under the curve was 0.800 (Fig). CONCLUSIONS: FDG-PET/CT was effective to detect UUTC. Furthermore, SUVmax had a role of supplementary index. FDG-PET/ CT may be able to replace of endoscopic biopsy depending on the patients. Source of Funding: none
Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1997
We examined whether 201Tl myocardial scintigraphy with intravenous infusion of adenosine triphosp... more We examined whether 201Tl myocardial scintigraphy with intravenous infusion of adenosine triphosphate (ATP) can be substituted for dipyridamole (DIP) in the diagnosis of coronary artery disease CAD). The coronary flow reserve (CFR) during intravenous infusion of ATP (0.10-0.20 mg/kg/min) was compared with that during intravenous infusion of DIP (0.56 mg/kg) using a Doppler flow wire in 19 subjects with normal coronary arteries. The highest CFR level was found in the ATP dose range of 0.16-0.20 mg/kg/min. The CFR at the ATP dose of 0.16 mg/kg/min was significantly higher than that during DIP infusion (4.2 versus 3.6) (p < 0.01), for which reason we adopted this dose of ATP. According, 201Tl SPECT in 140 patients with suspected CAD was performed after infusion of 0.16 mg/kg/min of ATP in 70 of them and 0.56 mg/kg of DIP in the 70 others. ATP stress 201Tl SPECT showed no significant difference in sensitivity and accuracy from DIP stress 201Tl SPECT (87.0% versus 82.9, and 87.1% vers...
Kaku igaku. The Japanese journal of nuclear medicine, 1991
Journal of the American College of Cardiology, 2004
We sought to evaluate the time course of insulin-stimulated myocardial glucose uptake (MGU) in mi... more We sought to evaluate the time course of insulin-stimulated myocardial glucose uptake (MGU) in mice that had undergone ablation of glucose transporter-4 (GLUT4). BACKGROUND The relative importance of GLUT4, the most abundant insulin-responsive glucose transporter, to modulate myocardial glucose metabolism is not well defined. METHODS Myocardial glucose uptake was assessed at various time points after glucose (1 mg/g) and insulin (8 mU/g) injection in GLUT4-null (G4N) (n ϭ 48) and wild-type (WT) (n ϭ 48) mice with 18 F-2-deoxy-2-fluoro-D-glucose (FDG) using in vivo positron emission tomography (PET), in vitro gamma-counter biodistribution, and isolated, perfused hearts. RESULTS Baseline assessment with PET imaging showed comparable MGU in G4N (0.66 Ϯ 0.12) and WT (0.67 Ϯ 0.11, p ϭ 0.70) mice. Early after insulin injection, WT mice demonstrated a 3.5-fold increase in MGU (2.45 Ϯ 0.45, p ϭ 0.03), whereas G4N mice presented no increase (1.11 Ϯ 0.24, p ϭ 0.28). At 60 min, MGU was comparable in G4N (3.19 Ϯ 0.60) and WT (2.66 Ϯ 0.47, p ϭ 0.28) mice. In vitro gamma-counter biodistribution evaluation confirmed in G4N mice a lack of MGU increase early after insulin, but a slow response over 120 min. The isolated, perfused hearts of G4N mice during short-term (15 min) insulin stimulation displayed no increase in MGU (0.08 Ϯ 0.01 ml/g/min), whereas WT mice presented a threefold increase (0.22 Ϯ 0.01 ml/g/min, p Ͻ 0.01). With long-term (60 min) insulin stimulation, similar MGU was found in G4N (0.31 Ϯ 0.02 ml/g/min) and WT (0.33 Ϯ 0.04 ml/g per min, p ϭ 0.04) mice. CONCLUSIONS The G4N mice displayed an increase of MGU in response to insulin similar to that of controls, but with a markedly delayed time response. Our findings underscore the important role of GLUT4 in the rapid adaptive response of myocardial glucose metabolism.
European Journal of Nuclear Medicine, 1991
To evaluate the usefulness of myocardial scintigraphy as a monitoring tool for chronic doxorubici... more To evaluate the usefulness of myocardial scintigraphy as a monitoring tool for chronic doxorubicin (DXR) cardiotoxicity, a rat model was used to investigate the relationship between the myocardial uptake of thallium 201 (T1) or rechnetium 99m pyrophosphate (99mTc-PPi) and histological changes of the heart. Although there was no significant difference in myocardial T1 uptake between control and DXR-treated rats at an early phase after T1 injection, late-phase T1 uptake was significantly higher in the DXR-treated rats than in the control rats, indicating a slow wash-out of T1 from the myocardium. The wash-out rate calculated from scintigraphic examination of DXR-treated rats was significantly decreased with increasing degree of cardiomyopathy. Since the T1 wash-out rate was sharply decreased even in animals with minimal histological changes, it may be a possible monitoring tool for the early detection of chronic DXR cardiotoxicity. On the other hand, myocardial 99mTc-PPi images could be obtained only in rats with severe myocardial changes and hence would not useful for early detection.
Cardiovascular Research, 2005
Imaging of reporter gene expression holds promise for noninvasive monitoring of cardiovascular mo... more Imaging of reporter gene expression holds promise for noninvasive monitoring of cardiovascular molecular therapy. We investigated the feasibility of myocardial gene expression imaging in living rats using the human sodium/iodide symporter gene (hNIS) and widely available scintigraphic techniques. Methods: We injected adenovirus expressing hNIS under control of cytomegalovirus promoter (Ad hNIS) directly into left ventricular myocardium of Wistar rats. For detection of reporter gene expression, dynamic gamma-camera imaging was performed following intravenous injection of 123 Iodide or 99m Technetium. Results: For both radiotracers, focal cardiac accumulation was identified as early as 10 min, and remained detectable until 2 hrs after injection, while it was not present in animals injected with LacZ control virus. Intensity of tracer accumulation gradually decreased when decreasing titers of Ad hNIS were applied. Treatment with sodium perchlorate (a blocker of hNIS) abolished cardiac tracer uptake after Ad hNISinfection. Serial imaging after cardiac gene transfer demonstrated a peak of tracer signal between days 1 and 3, and a subsequent decrease until day 12. Postmortem analysis of hearts yielded significant correlation between in vivo radiotracer accumulation and ex vivo gammacounting. Autoradiography demonstrated specific regional radioactivity in Ad hNIS-infected myocardial areas. Conclusions: hNIS offers a practical and reliable approach for myocardial gene expression imaging. Using suitable vectors, hNIS may be coexpressed with therapeutic genes or stably expressed in stem cells for future monitoring of cardiovascular molecular therapy.
Annals of Nuclear Medicine, 2014
Annals of Hematology, 2012
The treatment of patients with diffuse large B cell lymphoma (DLBCL) would be greatly facilitated... more The treatment of patients with diffuse large B cell lymphoma (DLBCL) would be greatly facilitated with a rapid method for determining prognosis that can be performed more easily and earlier than cytological or specific pathological examinations. It has been suggested that newly diagnosed patients with DLBCL who have low maximum standard uptake value (SUV max) on 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) are more likely to be successfully treated and remain in remission compared with patients with high SUV max , but this concept has been poorly studied. We retrospectively analyzed 50 patients with de novo DLBCL to evaluate the relationship between the SUV max and disease progression. For patients with low SUV max (n010) and high SUV max (n040) (P00.255), respectively, the 3-year overall survival rates were 90 and 72 %, and the progressionfree survival (PFS) rates were 90 and 39 % (P00.012). By multivariate analysis, the revised International Prognostics Index (R-IPI) and SUV max at diagnosis were shown to predict longer PFS. The 3-year PFS for patients with low SUV max classified into the good prognosis group by R-IPI was 100 vs. 62 % for those with high SUV max (P00.161), and patients with low SUV max classified into the poor prognosis group by R-IPI was 80 vs. 18 % for those with high SUV max (P00.050). We conclude that the SUV max on FDG-PET for newly diagnosed patients with DLBCL is an important predictor of disease progression, especially for patients with poor prognosis by R-IPI.
American Journal of Roentgenology, 2002
Japanese Circulation Journal, Mar 1, 1994