Epidemiology of Coronavirus Disease Outbreak among Crewmembers on Cruise Ship, Nagasaki City, Japan, April 2020.

In April 2020, a coronavirus disease (COVID-19) outbreak occurred on the cruise ship Costa Atlantica in Nagasaki, Japan. Our outbreak investigation included 623 multinational crewmembers onboard on April 20. Median age was 31 years; 84% were men. Each crewmember was isolated or quarantined in a single room inside the ship, and monitoring of health status was supported by a remote health monitoring system. Crewmembers with more severe illness were hospitalized. The investigation found that the outbreak started in late March and peaked in late April, resulting in 149 laboratory-confirmed and 107 probable cases of infection with severe acute respiratory syndrome coronavirus 2. Six case-patients were hospitalized for COVID-19 pneumonia, including 1 in severe condition and 2 who required oxygen administration, but no deaths occurred. Although the virus can spread rapidly on a cruise ship, we describe how prompt isolation and quarantine combined with a sensitive syndromic surveillance system can control a COVID-19 outbreak.

Unusual small subunit that is not expressed in photosynthetic cells alters the catalytic properties of rubisco in rice.

Rubisco small subunits (RbcSs) are encoded by a nuclear multigene family in plants. Five RbcS genes, OsRbcS1, OsRbcS2, OsRbcS3, OsRbcS4, and OsRbcS5, have been identified in rice (Oryza sativa). Among them, the amino acid sequence of OsRbcS1 differs notably from those of other rice RbcSs. Phylogenetic analysis showed that OsRbcS1 is genetically distant from other rice RbcS genes and more closely related to RbcS from a fern and two woody plants. Reverse transcription-PCR and promoter ß-glucuronidase analyses revealed that OsRbcS1 was not expressed in leaf blade, a major photosynthetic organ in rice, but was expressed in leaf sheath, culm, anther, and root central cylinder. In leaf blade of transgenic rice overexpressing OsRbcS1 and leaf sheath of nontransgenic rice, OsRbcS1 was incorporated into the Rubisco holoenzyme. Incorporation of OsRbcS1 into Rubisco increased the catalytic turnover rate and Km for CO2 of the enzyme and slightly decreased the specificity for CO2, indicating that the catalytic properties were shifted to those of a high-activity type Rubisco. The CO2 assimilation rate at low CO2 partial pressure was decreased in overexpression lines but was not changed under ambient and high CO2 partial pressure compared with nontransgenic rice. Although the Rubisco content was increased, Rubisco activation state was decreased in overexpression lines. These results indicate that the catalytic properties of Rubisco can be altered by ectopic expression of OsRbcS1, with substantial effects on photosynthetic performance in rice. We believe this is the first demonstration of organ-specific expression of individual members of the RbcS gene family resulting in marked effects on Rubisco catalytic activity.

Japanese Encephalitis Virus Genotypes 1 and 3 Isolation in Kochi, Japan.

Japanese encephalitis virus (JEV) is a mosquito-borne virus belonging to the JEV serocomplex within the genus Flavivirus, family Flaviviridae. It has 5 genotypes, G1-G5, based on the envelope (E) protein nucleotide sequence. JEV G3 circulated in Japan until the early 1990s when it was replaced by G1. JEV G3 was isolated from swine serum samples (sw/Kochi/1/2004) in the Kochi Prefecture, western Japan, in 2004. In addition, the 2018 isolates from pigs and cows (sw/Kochi/492/2018 and bo/Kochi/211/2018) in the same prefecture were identified as G3. The nucleotide sequencing results of the sw/Kochi/492/2018 and bo/Kochi/211/2018 polyprotein region differed from those of the sw/Kochi/1/2004 strain described in our previous report. Seven JEV isolates were identified as G1 in the same geographical area as that in this study. This result indicates that both JEV G1 and G3 are present in the Kochi area.

Development of monoclonal antibody based IgG and IgM ELISA for diagnosis of severe fever with thrombocytopenia syndrome virus infection.

INTRODUCTION: Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly emerged virus that poses a great threat to human health because of high fatality rate. METHODS: To develop sensitive and specific sero-diagnostic systems for SFTSV infections, monoclonal antibodies (MAbs) against recombinant SFTSV nucleocapsid (rSFTSV-N) protein were developed by immunizing BALB/C mice with rSFTSV-N protein and fusing the spleen cells with SP2/0 myeloma cells. Three hybridoma cell lines secreting MAbs against rSFTSV-N were obtained. MAb based IgG sandwich enzyme linked immunosorbent assay (ELISA) and IgM capture ELISA systems were established by using the newly developed MAbs. One hundred fifteen clinical suspected SFTS patients serum samples were used to evaluate the newly established systems by comparing with the total antibody detecting sandwich ELISA system and indirect ELISA systems. RESULTS: The MAbs based sandwich IgG ELISA was perfectly matched with that of the total antibody sandwich ELISA and the indirect IgG ELISA. IgM capture ELISA results perfectly matched with that of the total antibody sandwich ELISA while detecting eight additional positive samples missed by the indirect IgM ELISA. CONCLUSIONS: The MAbs against rSFTSV-N protein offer new tools for SFTSV studies and our newly developed MAb-based IgG and IgM capture ELISA systems would offer safe and useful tools for diagnosis of SFTS virus infections and epidemiological investigations.

Long-term smoking causes more advanced coronary endothelial dysfunction in middle-aged smokers compared to young smokers.

PURPOSE: Smoking cessation has been shown to normalize the coronary endothelial dysfunction in healthy young smokers. However, its effect has not been explored in middle-aged smokers with a longer history of smoking. Therefore, we compared the effects of smoking cessation on coronary vasomotor response between both young and middle-aged smokers and identified the predictor for its improvement. METHODS: This study investigated 14 young healthy smokers (age 25.2 ± 2.3 years), 13 middle-aged smokers (age 42.0 ± 6.5 years) and 10 non-smokers. Myocardial blood flow (MBF) was measured by using (15)O-water positron emission tomography (PET). RESULTS: At baseline, the ratio of MBF during the cold pressor test (CPT) to that at rest (MBF(CPT/rest)), the index of coronary endothelial function, was significantly decreased in both young and middle-aged smokers compared to non-smokers (1.24 ± 0.20 and 1.10 ± 0.39 vs 1.53 ± 0.18, p < 0.05 and p < 0.001, respectively). The ratio of MBF during adenosine triphosphate infusion to that at rest was significantly decreased in middle-aged smokers compared to young smokers and non-smokers (3.34 ± 1.52 vs 4.43 ± 0.92 and 4.69 ± 1.25, p < 0.05, respectively). MBF(CPT/rest) at 1 month after smoking cessation significantly increased in young smokers, but not in middle-aged smokers. By multivariate analysis, baseline serum malondialdehyde-modified low-density lipoprotein (MDA-LDL) was an independent predictor for the changes in MBF(CPT/rest) after smoking cessation (ß = -0.45, p < 0.05). CONCLUSION: Coronary endothelial dysfunction was reversible by short-term smoking cessation in young smokers, but not in middle-aged smokers, which was associated with serum MDA-LDL levels. Long-term smoking exposure could lead to more advanced coronary endothelial dysfunction and atherosclerosis possibly via oxidative stress.

Tacrolimus-induced pulmonary injury in rheumatoid arthritis patients.

BACKGROUND: Tacrolimus (TAC) was approved in Japan in 2005 for rheumatoid arthritis (RA) patients having inadequate response to other disease-modifying anti-rheumatic drugs. As of May 2007, spontaneous reports identified twenty-seven cases of exacerbation or new development of interstitial pneumonia among RA patients given TAC in Japan. OBJECTIVE: To describe the clinical and radiological characteristics of TAC-induced pulmonary injury (TIPI). PATIENTS AND METHODS: Eleven RA patients diagnosed with de novo pulmonary injury or exacerbation of IP during treatment with TAC were identified. Clinical, radiological, and laboratory data of ten of these cases were retrospectively analyzed. RESULTS: Baseline data for the ten patients were a mean age of 69.7 years; gender, 70% female; mean RA disease duration, 9.1 years; and pulmonary comorbidities, 90%. Six cases were classified as presumptive TAC-induced pulmonary injury (TIPI) and four as probable TIPI. Among the six presumptive cases, TIPI developed at an average of 84 days after initiation of treatment (n = 5) or four days after reinstitution of TAC (n = 1). Five cases were an exacerbation of pre-existing interstitial pneumonia and one was a de novo pulmonary injury. Radiological patterns of thoracic computed tomography (CT) scans of patients in the presumptive TIPI cases were hypersensitivity pneumonia like-pattern (n = 3), ground-glass opacity (n = 2), and organizing pneumonia-pattern (n = 1). All patients with presumptive TIPI were treated with high dosage glucocorticosteroids and one received concomitant immunosuppressants. Two of the six presumptive TIPI patients died. CONCLUSION: Rheumatologists should be aware of this rare but potentially life-threatening adverse event in RA patients receiving TAC.

Dengue virus type 2 recognizes the carbohydrate moiety of neutral glycosphingolipids in mammalian and mosquito cells.

Dengue viruses infect cells by attaching to a surface receptor which remains unknown. The putative receptor molecules of dengue virus type 2 on the surface of mosquito (AP-61) and mammalian (LLC-MK2) cell lines were investigated. The immunochemical detection and structural analysis of carbohydrates demonstrated that the neutral glycosphingolipids, L-3 (GlcNAcß1-3Manß1-4Glcß1-1'Cer) in AP-61 cells, and nLc(4) Cer (Galß1-4GlcNAcß1-3Galß1-4Glcß1-1'Cer) in LLC-MK2 cells were recognized by the virus. These findings strongly suggest that neutral glycosphingolipids share the key determinant for virus binding and that the ß-GlcNAc residue may play an important role in dengue virus binding to the host cell surface.

Impaired myocardial blood flow reserve in subjects with metabolic syndrome analyzed using positron emission tomography and N-13 labeled ammonia.

PURPOSE: Coronary vasomotor response might be impaired in metabolic syndrome (MS); however, the precise abnormality has not been elucidated. The aim of this study was to assess coronary-vasomotor response in MS subjects using N-13 labeled ammonia and positron emission tomography. METHODS AND RESULTS: Myocardial blood flow (MBF) was measured at rest and during adenosine infusion in MS subjects (n = 13, MS group) with no definite evidence of heart disease and in subjects without MS (n = 14, non-MS group). Coronary vascular resistance (CVR) was calculated by dividing the mean aortic blood pressure by MBF. Myocardial blood flow reserve (MFR) was calculated as the ratio of the MBF during adenosine infusion to that during rest. Blood chemical parameters were measured to evaluate their relationship with MFR. During adenosine infusion, MBF was lower (p = 0.0085) and CVR higher (p = 0.0128) in the MS group than in the non-MS group and MFR was significantly lower in the MS group than in the non-MS group (2.13 +/- 0.99 vs. 3.38 +/- 0.95, p = 0.0027). Multivariate analysis demonstrated that the homeostasis model assessment-insulin resistance (p < 0.05) and the presence of hypertension (p < 0.05) were independent determinants of MFR. CONCLUSIONS: The results indicate that MFR was impaired in MS subjects, suggesting that an abnormal coronary microvascular response occurred in these subjects. This abnormality may have been partially due to insulin resistance and hypertension.

Effect of Sulfur Variation on the Vulcanizate Structure of Silica-Filled Styrene-Butadiene Rubber Compounds with a Sulfide-Silane Coupling Agent.

The vulcanizate structure of filled compounds is affected by filler-rubber interactions (FRI) and the chemical crosslink density (CCD) of the matrix rubber. In particular, in filled compounds using a silica-silane system, FRIs due to silica-rubber coupling are a major influencing factor for the vulcanizate structure and physical properties. In this study, the effect of sulfur variation on the vulcanizate structure of silica-filled solution styrene-butadiene rubber compounds using a sulfide-silane coupling agent was studied. The vulcanizate structure according to sulfur variation was quantitatively analyzed using the swelling test and Flory-Rehner and Kraus equations. As the sulfur content increased, both FRI and the CCD increased, and it was confirmed that sulfur variation influenced the silica-rubber coupling efficiency through increased FRI. In addition, field emission scanning electron microscope images showed that increased FRI contributed to improvements in silica dispersion, abrasion resistance, and energy loss characteristics.

Myocardial beta-adrenergic receptor density assessed by 11C-CGP12177 PET predicts improvement of cardiac function after carvedilol treatment in patients with idiopathic dilated cardiomyopathy.

UNLABELLED: We evaluated whether myocardial beta-adrenergic receptor (beta-AR) density, as determined by 11C-CGP12177 PET, could predict improvement of cardiac function by beta-blocker carvedilol treatment in patients with idiopathic dilated cardiomyopathy (IDC). METHODS: Ten patients with IDC (left ventricular ejection fraction [LVEF]<45%) were studied. Myocardial beta-AR density was estimated using 11C-CGP12177 PET before treatment with carvedilol. Changes of LVEF in response to dobutamine infusion (DeltaLVEF-dobutamine) were also measured by echocardiography. Changes of LVEF (DeltaLVEF-carvedilol) were evaluated after 20 mo of carvedilol treatment. RESULTS: Baseline myocardial beta-AR density significantly correlated with DeltaLVEF-carvedilol (r=-0.88, P<0.001). In contrast, DeltaLVEF-dobutamine did not correlate with DeltaLVEF-carvedilol (P=0.65). Myocardial beta-AR density was the significant multivariate independent predictor of DeltaLVEF-carvedilol (beta=-0.88, P<0.001) among univariate predictors, including functional class (r=0.76, P<0.05), plasma norepinephrine (r=0.85, P<0.01), LVEF (r=-0.64, P<0.05), and age as confounding factors. Furthermore, myocardial beta-AR density was significantly correlated with plasma norepinephrine (r=-0.79, P<0.01) and LVEF (r=0.70, P<0.05). CONCLUSION: Myocardial beta-AR density is more tightly related to improvement of LVEF-carvedilol than is cardiac contractile reserve in patients with IDC. Patients with decreased myocardial beta-AR have higher resting adrenergic drive, as reflected by plasma norepinephrine, and may receive greater benefit from being treated by antiadrenergic drugs.

Nuclear medicine practice in Japan: a report of the sixth nationwide survey in 2007.

OBJECTIVE: The Subcommittee on the Survey of Nuclear Medicine Practice in Japan has performed a nationwide survey of nuclear medicine practice every 5 years since 1982 to provide detailed information on its present status. METHODS: Questionnaires were sent to all institutions known to the Japan Radioisotope Association to conduct nuclear medicine examinations. The questionnaires addressed the number and kind of nuclear medicine examinations performed as well as the kind and dose of the radiopharmaceuticals used during the month of June 2007. The annual number of total or specific examinations was then estimated. RESULTS: Of the institutions sent questionnaires, 1219 were for in vivo study, 49 for in vitro study, and 212 for positron emission tomography (PET) study. Of these, 92.2% provided answers. A total of 1569 gamma cameras were installed in 1119 institutions, of which 70% were dual-head cameras. The estimated total annual number of in vivo examinations expressed by the number of administered radiopharmaceuticals was 1.41 million, representing a decrease of 11.5% when compared with that of the previous survey (2002). The frequency of study with respect to single-photon emission computed tomography (SPECT) slightly increased to 42.3% from 39.9% in the previous survey. The most frequently performed scintigraphy was bone (38.3%), followed by myocardium (26.2%) and brain perfusion (14.1%). Brain perfusion scintigraphy slightly increased, whereas tumor scintigraphy decreased by one-half when compared with the previous survey. The most commonly used radiopharmaceutical for each scintigraphy was (99m)Tc-HMDP for bone, thallium-201 ((201)Tl)-chloride for myocardium, gallium-67 ((67)Ga)-citrate for tumor, and technetium-99m-ethylcysteinate dimmer ((99m)Tc-ECD) for brain. The number of PET institutes increased from 36 to 212. (18)F-fluorodeoxyglucose ((18)F-FDG)-PET dramatically increased 14.8-fold during the past 5 years. Radionuclide therapy also increased. (131)I therapy for thyroid cancer and hyperthyroidism was conducted yearly in 2373 and 4146 patients, respectively. A total of 13.1 million in vitro radioassays were carried out yearly, the number of which has been decreasing continuously since 1992. CONCLUSIONS: It was proved that the content of nuclear medicine practice in Japan has changed considerably in the past 5 years. Namely, (18)F-FDG-PET and radionuclide therapy increased. This report might be useful for understanding the present trends of nuclear medicine practice in Japan.

Neutralization Potency of Sera from Vietnamese Patients with Japanese Encephalitis (JE) against Genotypes I and V JE Viruses.

Japanese encephalitis virus (JEV) is classified into 5 genotypes (GI, GII, GIII, GIV, and GV), and the GI and GIII strains are the most widely distributed in JE endemic areas. In recent years, GV JEV has been detected in China and Korea, suggesting that GV JEV may invade other JE endemic areas, including Vietnam, and that more attention should be paid to the JEV strains circulating in these areas. In this study, we investigated the neutralization ability of the sera collected from 22 Vietnamese patients with JE who lived in northern Vietnam against the GI and GV JEV strains. In most cases, the ratios of the titer against GV to that against GI (GV:GI) were equal to or less than 1:4. However, the titer against GV JEV was equivalent (1:1) to that against GI JEV in only a few cases, and no serum had a ratio higher than 1:1. Thus, our results did not show convincing evidence that GV JEV was emerging in northern Vietnam in 2014.

Structure and anti-dengue virus activity of sulfated polysaccharide from a marine alga.

A sulfated polysaccharide, named fucoidan, from the marine alga Cladosiphon okamuranus is comprised of carbohydrate units containing glucuronic acid and sulfated fucose residues. Here we found this compound potently inhibits dengue virus type 2 (DEN2) infection. Viral infection was inhibited when DEN2, but not other serotypes, was pretreated with fucoidan. A carboxy-reduced fucoidan derivative in which glucuronic acid was converted to glucose did not inhibit viral infection. Elimination of the sulfated function group from fucoidan significantly attenuated the inhibitory activity on DEN2 infection with <1% fucoidan. DEN2 particles bound exclusively to fucoidan, indicating that fucoidan interacts directly with envelope glycoprotein (EGP) on DEN2. Structure-based analysis suggested that Arg323 of DEN2 EGP, which is conformationally proximal to one of the putative heparin binding residues, Lys310, is critical for the interaction with fucoidan. In conclusion, both the sulfated group and glucuronic acid of fucoidan account for the inhibition of DEN2 infection.

Decreased myocardial beta-adrenergic receptor density in relation to increased sympathetic tone in patients with nonischemic cardiomyopathy.

UNLABELLED: Cardiac sympathetic function plays an important role in the regulation of left ventricular (LV) function and the pathophysiology of LV dysfunction. (11)C-CGP-12177 ((11)C-CGP) has been used to assess myocardial beta-adrenergic receptor (beta-AR) density in vivo using PET. The aim of this study is to measure myocardial beta-AR density in patients with nonischemic cardiomyopathy and to compare the measurements with various standard parameters of heart failure (HF), particularly with presynaptic function assessed by (123)I- metaiodobenzylguanidine ((123)I-MIBG) imaging. METHODS: (11)C-CGP PET was performed on 16 patients with nonischemic cardiomyopathy and 8 age-matched healthy volunteers using a double injection method. A (11)C-CGP dynamic scan for 75 min was performed after the injection of (11)C-CGP with a high specific activity. After 30 min, (11)C-CGP with a low specific activity was injected. The beta-AR density of the whole LV was calculated on the basis of the graphical analysis method. Additionally, beta-AR density was compared with LV ejection fraction (LVEF), sympathetic presynaptic function assessed using (123)I-MIBG kinetics, and neurohormonal parameters. RESULTS: The beta-AR density of patients was significantly lower than that of healthy volunteers (3.80 +/- 0.96 vs. 7.70 +/- 1.92 pmol/mL; P < 0.0001). In the patients, beta-AR density correlated significantly with LVEF (r = 0.62, P < 0.05). Furthermore, beta-AR density correlated significantly with the (123)I-MIBG washout rate (r = -0.68, P < 0.01) and delayed heart-to-mediastinum ratio (H/M ratio) (r = 0.61, P < 0.05). On the other hand, the correlation between beta-AR density and early H/M ratio was not significant (r = 0.40, P = 0.13). The beta-AR density of patients with severe HF (New York Heart Association functional [NYHA] class III) was significantly lower than that of those with NYHA functional class I or class II HF (3.24 +/- 0.96 vs. 4.24 +/- 0.73 pmol/mL; P < 0.05). CONCLUSION: A reduction in beta-AR density measured by (11)C-CGP PET was observed in patients with nonischemic cardiomyopathy. This downregulation may be due to the increased presynaptic sympathetic tone as assessed by (123)I-MIBG imaging.

Plasma interleukin-6 and tumor necrosis factor-alpha can predict coronary endothelial dysfunction in hypertensive patients.

Coronary endothelial function is impaired in hypertension; however, the severity of this impairment varies among patients. We aimed to identify the predictors of coronary endothelial dysfunction among clinical variables related to hypertension and atherosclerosis. Twenty-seven untreated, uncomplicated essential hypertensive patients and 10 age-matched healthy controls were studied prospectively. Myocardial blood flow (MBF) was measured by using (15)O-water positron emission tomography (PET) at rest and during a cold pressor test (CPT). Coronary vascular resistance (CVR) during CPT was used as a marker of coronary endothelial function. Serum low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, triglycerides, malondialdehyde-LDL, homeostasis model assessment, high-sensitivity C-reactive protein (hs-CRP), and plasma interleukin-6 (IL-6) and tumor necrosis factor (TNF)-alpha were also measured. CVR during CPT was significantly higher in hypertensive patients than in healthy controls (114+/-26 vs. 94+/-12 mmHg/[mL/g/min]; p<0.05). By univariate analysis, CVR during CPT was correlated with LDL cholesterol (r=0.38, p<0.05), IL-6 (r=0.46, p<0.02), and TNF-alpha (r=0.39, p<0.05) in hypertensive patients. By multivariate analysis, IL-6 and TNF-alpha were significant independent predictors of CVR during CPT. Elevated plasma IL-6 and TNF-alpha levels were independent predictors of coronary endothelial dysfunction in hypertensive patients. These results suggest that plasma IL-6 and TNF-alpha might be useful for identifying the high risk subgroup of hypertensive patients with coronary endothelial dysfunction and provide an important clue to link systemic inflammation to the development of coronary atherosclerosis.

Assessment of myocardial perfusion by dynamic O-15-labeled water PET imaging: validation of a new fast factor analysis.

BACKGROUND: Factor analysis (FA) is an established method for separating myocardium from blood pool by use of oxygen 15-labeled water and positron emission tomography for analyzing myocardial blood flow (MBF). Conventional FA methods generating images from sinograms (sinoFA) are time-consuming, whereas FA can be performed on the reconstructed images (reconFA) in a fraction of time. We validated the MBF values obtained by reconFA versus sinoFA. METHODS AND RESULTS: In 23 volunteers (mean age, 26.6 +/- 3.4 years) MBF was calculated from sinoFA and reconFA and blindly reanalyzed 1 month later by the same observer. Intraobserver agreement and reconFA-versus-sinoFA agreement were assessed according to Bland and Altman (BA). Reproducibility proved excellent for global sinoFA (r = 0.968; P < .001; BA limits, -0.617 to 0.676 mL x min(-1) x g(-1)) and slightly superior for reconFA (r = 0.979; P < .001; BA limits, -0.538 to 0.558 mL x min(-1) x g(-1)), with wider limits of agreement for segmental MBF from sinoFA (r = 0.777; P < .001; BA limits, -1.676 to 1.656 mL x min(-1) x g(-1)) and reconFA (r = 0.844; P < .001; BA limits, -1.999 to 1.992 mL x min(-1) x g(-1)). In addition, sinoFA and reconFA showed excellent correlation (r = 0.975, P < .001) and agreement (BA limits, -0.528 to 0.648 mL x min(-1) x g(-1)) for global and segmental values (r = 0.955; P < .001; BA limits, -1.371 to 1.491 mL x min(-1) x g(-1)). CONCLUSIONS: Use of reconFA allows rapid and reliable quantitative MBF assessment with O-15-labeled water.

Whole-body iodine-131 metaiodobenzylguanidine imaging for detection of bone metastases in patients with paraganglioma: comparison with bone scintigraphy.

Iodine-131 metaiodobenzylguanidine ((131)I-MIBG) therapy is an effective treatment for patients with malignant paraganglioma for which surgical resection is not indicated. We performed high-dose (131)I-MIBG therapy on two patients with malignant paraganglioma and multiple bone metastases. The bone metastases were diagnosed by magnetic resonance imaging (MRI). Metastatic bone lesions were evaluated by whole-body (131)I-MIBG imaging and bone scintigraphy. Whole-body (131)I-MIBG imaging showed extensive metastatic bone lesions, whereas conventional bone scintigraphy did not. There was a remarkable discrepancy between (131)I-MIBG imaging and bone scintigraphy in the diagnosis of metastatic bone lesions of malignant paraganglioma in our two patients. High-dose (131)I-MIBG imaging may detect early stages of bone metastases, compared with bone scintigraphy, in patients with malignant paraganglioma.

Creation and characterization of Japanese standards for myocardial perfusion SPECT: database from the Japanese Society of Nuclear Medicine Working Group.

OBJECTIVE: Standards for myocardial single-photon emission computed tomography (SPECT) adapted for a Japanese population were not available. The purpose of this study was to create standard files approved by the Japanese Society of Nuclear Medicine and to make known the characteristics of the myocardial perfusion pattern of this population. METHODS: With the collaboration of nine hospitals, a total of 326 sets of exercise-rest myocardial perfusion images were accumulated from subjects with a low likelihood of cardiac diseases. The normal database included a (99m)Tc-MIBI/tetrofosmin myocardial perfusion study with 360 degrees (n = 80) and 180 degrees (n = 56) rotations, (201)Tl study with 360 degrees (n = 115) and 180 degrees rotations (n = 54) and a dual-isotope study with 360 degrees rotation (n = 27). The projection images were transferred by digital imaging and communications in medicine (DICOM) format and reconstructed and analyzed with polar maps. RESULTS: The projection data from multiple centers were successfully transferred to a common format for SPECT reconstruction. When the average values were analyzed using a 17-segment model, myocardial counts in the septal segment differed significantly between 180 degrees and 360 degrees rotation acquisitions. Regional differences were observed between men and women in the inferior and anterior regions. A tracer difference between (99m)Tc and (201)Tl was also observed in some segments. The attenuation patterns differed significantly between subjects from the United States and those from Japan. CONCLUSIONS: Myocardial perfusion data that were specific for the Japanese population were generated. The normal database can serve a standard for nuclear cardiology work conducted in Japan.

[Clinical value of 13N-ammonia PET in assessment of cardiac disease: meta-analysis].

The clinical value of 13N-ammonia PET is reviewed by using previously published articles with significant evidence level. This meta-analysis indicated that due to excellent myocardial blood flow images, 13N-ammonia PET permits better diagnostic accuracy of ischemic heart disease and viability assessment than myocardial perfusion SPECT. Furthermore, quantitative assessment of myocardial blood flow (MBF) in absolute units can be performed using 13N-ammonia PET. MBF measurement is a useful tool to evaluate cardiac pathophysiology and monitor therapeutic effects of cardiac disease and cardiovascular risk factors.

[Myocardial reporter gene expression imaging].

Radionuclide gene expression imaging can visualize and measure transcription activity of target genes noninvasively by co-expressing a reporter gene, of which product can be traced with complementary radioactive reporter probes. While in the cardiac field it was at first aiming at monitoring angiogenic gene therapy, its application is directed to cell tracking in stem/progenitor cell therapy, due to disappointing results in the clinical trials and potential risks of transfer vectors. In this article, we give a general outline of cardiac radionuclide gene expression imaging using reporter genes, including its principle, various combinations of reporter gene/reporter probe, the current status of cardiac gene therapy, and its application for cell tracking.