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A unique epitaxial process, dynamic atomic layer epitaxy (D-ALEp), has been proposed and developed to fabricate coherent monolayer-InN on/in GaN-matrix nanostructures. The D-ALEp utilizes self-limiting and self-ordering surface processes but differs from typical atomic layer epitaxy, because the growth front in D-ALEp dynamically changes stoichiometry or metal coverage through adsorption/desorption of adatoms at a high-temperature regime. The growth front is precisely traced by in situ spectroscopic ellipsometry monitoring, where atomic scale surface behavior is easily/accurately understood by our smart style of an imaginary part of pseudodielectric function normalized by an adlayer thickness (Δ〈ɛ2〉), instead of complicated spectral analysis. In this chapter, the authors briefly introduce the D-ALEp and also our prime objective to establish ordered alloys in a whole III-nitride system. Subsequently, the authors discuss growth kinetics of monolayer-InN on/in GaN-matrix by the D-ALEp which has been developed in molecular beam epitaxy (MBE) at the beginning to overcome highly mismatched problems in an InN/GaN system, and then investigated in metalorganic vapor phase epitaxy (MOVPE) as well. Finally, the authors represent an extension of the D-ALEp toward fabrication of III-N ordered alloys. The authors have demonstrated InN/GaN ordered alloys grown by MBE and (InN/GaN)-layer/pn-GaN solar cells grown by MOVPE. The authors further discuss a future prospect of AlN/GaN and AlN/InN ordered alloys for potential application to high electron mobility transistors (HEMTs).

The decomposition of glass fiber reinforced plastics (GFRP) with ethylene glycol monoallyl ether (EGMA) and benzyl alcohol (BnOH) by non-catalytic transesterification under high pressure, microwave irradiation was investigated. The decomposition product of GFRP with EGMA (EGMA-P) has a high reactivity for the cross-linking reaction to unsaturated polyester (UP) compared to the product of GFRP with BnOH (Bn-P) because of the presence of many allyl groups derived from EGMA. Therefore, the hardened material (EGMA-HM) with high thermal stability was prepared from EGMA-P, unsaturated polyester, and curing agent. Finally, the recycled GFRP with high bending breaking point was produced from EGMA-P.

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, three of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of models and technical issues involved in placenta research: 1) comparative placentation and animal models; 2) advanced techniques in placental histopathology; 3) human pluripotent stem cells as a model for trophoblast differentiation.

We review fundamental issues arising in the exact solution of the one-dimensional Hubbard model. We perform a careful analysis of the Lieb-Wu equations, paying particular attention to so-called `string solutions'. Two kinds of string solutions occur: $\Lambda$ strings, related to spin degrees of freedom and $k-\Lambda$ strings, describing spinless bound states of electrons. Whereas $\Lambda$ strings were thoroughly studied in the literature, less is known about $k-\Lambda$ strings. We carry out a thorough analytical and numerical analysis of $k-\Lambda$ strings. We further review two different approaches to the thermodynamics of the Hubbard model, the Yang-Yang approach and the quantum transfer matrix approach, respectively. The Yang-Yang approach is based on strings, the quantum transfer matrix approach is not. We compare the results of both methods and show that they agree. Finally, we obtain the dispersion curves of all elementary excitations at zero magnetic field for the less than half-filled band by considering the zero temperature limit of the Yang-Yang approach., Comment: 72 pages, 11 figures, revtex

A Holter recording system was established for the Göttingen miniature swine. For this purpose, we first developed a jacket to hold a Holter recording set, and subsequently determined a bipolar lead suitable for obtaining stable electrocardiogram (ECG) recording without artifacts. To make the jacket, we measured the lengths of eight sites of the body of 14 miniature swine. Several types of jackets were made and tested. We observed the behaviour of animals with these jackets by videotape recorder (VTR) recording. These observations permitted development of a jacket suitable for Holter recording. The jacket permits easy placement of the recorder, and long-term ECG recording can be performed without difficulty. In order to determine a suitable lead for long-term recording, we recorded ECGs from six adult miniature swine using three types of leads, the M-X, R-L and A-B leads. The R-L lead frequently exhibited baseline drift, and QRS complexes often disappeared in this lead due to low amplitude. ECG recording with the M-X and A-Bleads was of sufficient quality to permit analysis. This system is expected to be useful for further cardiovascular research in miniature swine.

Bubble column and three-phase fluidized bed reactors have wide applications in biotechnological and petroleum processes (Deckwer, 1985; Fan, 1989). In such biotechnological processes as fermentation and waste water treatment, small bubbles of oxygen and/or nitrogen are introduced in the column to enhance oxygen transfer and to ensure the stability of immobilized cell particles. In addition, tiny bubbles are produced during the biological process due to the production of surface active compounds. The presence of these small bubbles causes an increase in the gas holdup of the system. High gas holdups are also characteristics of industrial processes such as coal liquefaction and hydrotreating of residual oils. Good understanding of the transport properties of three-phase fluidized beds with high gas holdups is essential to the design, control and optimum operations of the commercial reactors employed in the above-mentioned processes. Heat-transfer studies in three-phase fluidized beds have been reviewed recently by Kim and Laurent (1991). Past studies focused primarily on the measurements of time-averaged heat transfer from the column wall to bed (Chiu and Ziegler 1983; Muroyama et al., 1986) or on immersed heating objects to bed (Baker et al., 1978; Kato et al., 1984) in aqueous systems. Recently, Kumar et al. (1992)more » provided a mechanistic understanding of the heat transfer in bubbly-liquid and liquid-solid systems. The purpose of this work is to investigate the heat transfer in a three-phase fluidized bed under high gas holdup conditions. The associated hydrodynamic behavior of the system is also studied.« less

The complex behavior of heat transfer in three-phase fluidized beds has been attributed to the interaction between phases which varies with the particle size, particle density, gas and liquid velocities. Three-phase fluidization with low-density particles is of considerable interest to biochemical applications. However, the understanding of heat transfer behavior in low-density systems is very limited. A special heat transfer probe is immersed in a three-phase fluidized bed and local instantaneous and time-averaged heat transfer coefficients are measured for calcium alginate beads and other low-density particles. In liquid—solid systems with low-density particles, the instantaneous heat transfer due to single-bubble passage exhibits a local maximum in the primary wake region caused by the enhanced surface renewal at the heat transfer surface. Enhancement in heat transfer due to bubble wake increases with bubble size but decreases with increasing particle density. Accordingly, relative enhancement in time-averaged heat transfer in three-phase systems over liquid—solid fluidized beds is higher for low-density particles compared to heavier particles under identical gas and liquid velocities. Local time-averaged heat transfer in low-density beds is found to be relatively independent of liquid velocity for gas velocity higher than 3 cm/s. Distributor effects on the flow regime and thereby the heat transfer are significant for low-density particles. The heat transfer is observed to be higher in the coalesced flow regime compared to that in the dispersed flow regime primarily due to significant bubble-wake effects. Axial variations in heat transfer coefficients are also observed for systems containing intermediate-density particles due to axial nonuniformities in solids holdup.

The chemical and physical structure of ion-implanted silicone rubbers has been studied in order to analyze their blood compatibility such as reduction of platelet accumulation owing to ion implantation. H + 2 , He + , C + , O + , O + 2 , N + , N + 2 , Ne + , Na + , Ar + , K + , and Kr + ion implantations were performed at an energy of 150 keV with fluences between 1 × 10 17 and 3 × 10 17 ions/cm 2 at room temperature. Results of FT-IR-ATR showed that ion implantation broke the original chemical bond to form new radicals such as OH, >C = O, SiH, and CH 2 . The formation of these radicals depended on the ion species employed: >C = O formation by O + or O + 2 implantation and formation of amines by N + or N + 2 implantation. The results of Raman spectroscopy showed that ion implantation always produced a peak at near 1500 cm −1 , although the intensity of this peak was dependent on the ion species. The light ions like H + 2 and He + were more effective than heavy ions in producing this peak, and O + 2 implantation was the most effective on producing amorphous carbon. These results indicated that >C = O and amorphous carbon, generated by O + 2 implantation, may improve the antithrombogenicity. The antithrombogenicity was tested by the superior vena cava (SVC) indwelling method for two days in rats with in-111-tropolone-platelets, and by the inferior vena cava (IVC) indwelling method for periods of 1–4 weeks in dogs. Results of the SVC indwelling method showed that platelet accumulation on H + 2 and O + 2 implanted specimens decreased. In particular 1 × 10 17 O + 2 /cm 2 implantation caused both accumulation onto specimens and the SVC to decrease. Macroscopic views of the ion-implanted IVC specimens in dogs revealed little thrombus formation. It is concluded that ion implantation into silicone rod is a useful technique to improve its antithrombogenicity.

Local instantaneous changes in heat-transfer coefficients due to the passage of gas bubbles in liquid and liquid-solid systems are measured. A special heat-transfer probe is developed and located within the bed to trace the instantaneous local heat-transfer rate during the passage of single gas bubbles. A microfoil heat flow sensor is attached to a foil heater, and the sensor-heater probe assembly can accurately measure the heat flux and the surface temperature over a small area. Signals from the sensor are amplified and interfaced with the microcomputer data acquisition system. Simultaneous visualization is performed using a high-speed video camera and a borescope to establish the correspondence between the visual and sensor signals, and hence relate the local instantaneous hydrodynamics to the heat-transfer rate. Local heat-transfer coefficient vs. time traces are analyzed in conjunction with visual signals. The heat-transfer coefficient exhibits a sharp peak in the bubble wake. In both liquid and liquid-solid systems, the observed local maximum in heat-transfer coefficient behind a rising bubble is due to the bubble-wake-induced surface renewal. Enhancement in heat transfer due to the bubble increases with the size because of increased surface renewal caused by larger bubble wake and stronger vortices. The local maximum in heat transfer, however, is more pronounced in liquid than in liquid-solid systems.

Silicon-carbide-nitride films with different atomic contents were prepared by adjusting the nitrogen gas flow rate in a magnetron-sputtering apparatus. The surface electrical resistivity measured by the two-ring probe method increased exponentially with nitrogen content. X-ray photoelectron spectroscopy analysis showed that the electrical resistivity was enhanced by the formation of SiN bonding. Crystalline structure in the X-ray diffraction pattern was observed only for the film produced on substrate heated at high temperature and with low nitrogen content. The electrical resistivity of the film with lower nitrogen content was observed to increase with increasing substrate temperature.

We have studied the magnetic properties of a certain class of Hubbard models proposed as models for quantum atomic wires with flat single-particle bands. These Hubbard models belong to a class of models to which Mielke-Tasaki theorem for flat-band ferromagnetism can be applied. We also found that the Mielke-Tasaki theorem is applicable in networks of quantum atomic wires. The present findings will be useful for producing flat-band ferromagnetism in quantum atomic wires and two dimensional networks.

In recent years, positron-emitting labelled radiopharmaceuticals have come to be used in conjunction with positron emission tomography (PET) in various clinical diagnoses. Radiation exposure of the medical staff is a key issue in the design of PET facilities intended to handle large numbers of persons for PET diagnosis. As a first step, the radiation dose to individuals who received radiopharmaceuticals was calculated using a mathematical phantom model and the EGS4 electromagnetic cascade Monte Carlo code and MCNP Monte Carlo code. Dose rate behind a lead shield was also calculated for various lead thicknesses. The radiation dose distribution around a syringe containing a positron emitter was calculated. The calculated dose distributions were fitted to polynomial equations. These calculations were evaluated against measurements. The second step was to evaluate medical staff dose at a specified time by superimposing dose distribution from each person who received radioisotopes taking into account radioactive decay. In this way, we developed software to support PET facility operation, namely, planning, prediction, control of medical staff dose and facility operation. This system was also designed to schedule daily radiopharmaceuticals production and to manage radioactive wastes by taking decay time into account.

This chapter discusses flat-band ferromagnetism in organic crystals. The magnetic nanographite may be a realization of flat-band ferromagnetism known in a class of the Hubbard models. Graphite is known to be a typical semimetal that shows large diamagnetism in the normal state due to its special electronic states. The electronic band structure of graphite obtained by the local-density-approximation (LSDA) is displayed. In the LSDA method, exchange interaction and correlation effects are estimated by extrapolating the exchange-correlation energy obtained for some solvable systems. Accurate calculations for spin-polarized electron-gas systems and small molecules are helpful cardinal points. Effective field determined is spin dependent, and spin-polarized solution in the single-body description may be obtained. Ground-state properties of the Hubbard model depend on the parameters of the model. An exothermic reaction to synthesize magnetic nanographite is possible to design by considering fluorination. The DFT-LSDA calculation results in a magnetic solution with a spin-polarized monofluorinated zigzag edge. The magnetic graphite–diamond hybrid structures are also elaborated in the chapter.

We propose a method of object recog- nition using the knowledge of the object world de- scribed in a form of a frame structure. The hier- archical frame structure consists of two levels, an outline image level and an aspect graph level. Us- ing this database, we can recognize input object as an object that has the largest degree of similar- ity between input edge image and outline images and/or aspect graphs in the database. Firstly, we calculate the degree of similarity between the in- put image and images in the database on the out- line level. As a result of this, we can narrow down the candidates and refine the extracted edge image to more precise edge line image on the aspect level. In this point, it is available to recognize objects on high recognition rates. In the case that the object world consists of five kinds of chairs composed by polygonal surfaces, we show some experimental re- sults.

A simple self-transfer aid robotic system is proposed, and motion analysis of a transfer aid system is presented in this paper. A person with weak leg muscles who uses a wheel chair is assumed to be the target user. By using the self-transfer aid robotic system, a user can transfer between a wheel chair and a toilet, for example. The proposed self-transfer aid robotic system is a two DOF system of a single link robotic arm with a saddle on the top, and a horizontal rotation mechanism driven manually. A user puts his/her belly on the saddle of the robotic arm, and then the robotic arm lifts the user's body. After rotating the user's body, the robotic arm lowers the user's body. The experiments on the burden measurements to human were conducted to design a simple self-transfer aid robotic system. Considering the experimental results, the self-transfer aid robotic system was fabricated.

Sympathetic cardiopulmonary nerves arise from the cervical sympathetic trunks and travel alongside the great arteries to innervate the ventricles. Because of the proximity of the nerve and artery, cardiac sympathetic denervation may occur in patients who have just undergone surgery for the repair of an ascending aortic aneurysm.To evaluate the cardiac sympathetic activity in aortic aneurysm, we performed cardiac 123I-metaiodobenzylguanidine (MIBG) imaging on 12 patients (mean age +/- SD, 47 +/- 17 y) before and after the surgical repair of an aneurysm. Seven patients scheduled for coronary artery bypass grafting also underwent 123I-MIBG imaging as controls for open-chest surgery. Planar images were obtained at 15 min (early) and 4 h (delayed) after injection of 111 MBq 123I-MIBG, and the cardiac 123I-MIBG uptake was graded quantitatively and visually. The quantitative evaluation was based on the heart-to-mediastinum ratio (H/M), and visual evaluation was performed by assigning a score of 0-3 (0 = absent, 1 = severely reduced, 2 = reduced, and 3 = normal). Heart rate variability using 24-h Holter electrocardiography was analyzed before and after the operation to generate a time-domain index of heart rate variability as an index of autonomic balance.In patients with aortic aneurysms, both early and delayed H/Ms were significantly decreased after the operation (early H/M: 1.84 +/- 0.16 before vs. 1.40 +/- 0.16 after, P = 0.001; delayed H/M: 1.79 +/- 0.38 before vs. 1.27 +/- 0.18 after, P = 0.004). Visual analysis of 123I-MIBG accumulation in early images showed absence of 123I-MIBG accumulation in 3 of 12 patients, a score of 1 in 7 patients, and a score of 2 in 2 patients. In contrast, no significant difference between H/M before surgery and H/M after surgery was seen in patients who underwent coronary artery bypass grafting. The time-domain index of heart rate variability was significantly lower after the operation than before (135 +/- 40 after vs. 96 +/- 27 before, P0.05).Cardiac sympathetic nerves are totally or partially denervated after the surgical repair of ascending aortic aneurysm.

Spark discharge in water generates a spherical shock wave and a bubble that contains water vapor, with each center at a gap between electrodes. The bubble repeats the movement of the expansion and contraction. An impulsive pressure wave also arises at each transition from the contraction to the expansion of the bubble. In case that a rigid wall exists near the bubble, the bubble moves toward it keeping the expansion and contraction and then a water jet is formed toward the wall. The jet exerts the impulsive pressure on the wall. In case that the bubble is near the surface of water, it moves as if a rigid wall existed just below it and then the downward water jet is also formed. We are interested in the relationship of the movement of the bubble to the effect of the pressure caused by the under-water discharge near the surface of water. We are also interested in whether there are some differences between the following two cases as to the effect of pressure; one case is that the bubble exists near the surface of water and its movement is affected by the surface, another case the movement of the bubble is not affected by the surface of water for the sake of enough large distance between the bubble and the surface. In this study, impulsive pressure waves caused by the under-water discharge in above two cases are observed by means of a transducer or their schlieren photographs are taken with an image converter camera, and observations are examined.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Using direct measurement, we investigated entrance surface doses of patients for routine radiographs in attempt to develop evaluation methods of patient dose in order to establish the guidance level in Japan. To date, patient doses have been evaluated by calculations based on radiographic conditions, or model experiments using phantoms. Their patient doses are then evaluated based on several assumptions. Direct measurement of patient dose is difficult to perform in many patients due to its time requirement, level of expertise required and difficulty in providing an explanation of the procedure to the patient. However, such direct measurement is essential since it incorporates all aspects of radiography from the radiographic equipment used, to the actual conditions of each patient without assumption. In this study, we examined the (1) need for introducing the guidance level, (2) controversial points in the calculation method for patient dose evaluation, (3) evaluation accuracy required for introducing the guidance level, and (4) necessity for a standardized method.

Phase III clinical study was performed to evaluate clinical utility of 123I-MIBG in the localization of tumors in 48 patients with tumors of sympathetic and adrenomedullary origin, diagnosed or strongly suspected. Sixteen patients had pheochromocytoma, 23 had neuroblastoma, 7 had medullary carcinoma of the thyroid, and 2 had Sipple syndrome. In 3 out of 48 patients, 123I-MIBG scintigraphy was performed twice. The clinical utility of 123I-MIBG was evaluated in 50 cases. Out of 140 lesions, 123I-MIBG scintigraphy demonstrated 51 true positive, 79 true negative, 1 false positive, and 2 false negative. Seven lesions were not evaluable. Sensitivity was 96.2%, Specificity was 98.8%, and Accuracy was 97.7%. An acquisition between 4 hrs and a day after injection was adequate for tumor detection. Neither adverse reactions nor abnormal laboratory findings were noted in relation to 123I-MIBG injections. Our study indicates that 123I-MIBG is a safe and useful radiotracer for visualization and localization of tumors of sympathetic and adrenomedullary origin.

Phase III clinical study in 78 patients with hyperparathyroidism was performed to determine clinical utility of 99mTc-MIBI in the localization of hyperfunctioning parathyroid lesions. Except slight tremor in one patient, no adverse events were reported. No abnormal changes in clinical laboratories or vital signs were noted. The clinical utility of the agent was evaluated in 70 patients. Out of 108 hyperfunctioning glands, 93 (86%) were detected with 99mTc-MIBI regardless of their histology, numbers, or location. Specifically, single or ectopic lesions were detected with high sensitivity (97% and 100%, respectively). Sensitivity in 53 glands with weight data was 79%, while 94% in 36 glands above 200 mg, which is extremely high compared to the 201T1-99mTc subtraction method. Specificity in a group of PHP patients with single adenoma who underwent surgery was 100% (63/63), though in case of coexistent thyroid disease obviously interfered parathyroid images. Our study indicates that 99mTc-MIBI is a safe and excellent agent for the localization of hyperfunctioning parathyroid tissues. Especially, the fact that 99mTc-MIBI detected ectopic glands with high specificity is a great advantage over the ultrasound or 201Tl-99mTc subtraction method.

Phase III clinical study in 136 patients diagnosed or strongly suspected of thyroid, lung/mediastinum or breast cancer was performed to determine clinical utility of 99mTc-MIBI in the localization of tumors, and the results in 135 were evaluated. Except taste peculiar in 43 patients and nausea in one, no adverse events were reported. Seven abnormal changes in vital signs and 27 in clinical laboratories were noted, which were all judged as having no or unlikely relationship to the agent. Out of 177 malignant lesions, 156 (88%) were detected with 99mTc-MIBI regardless of their histology or location. Of 6 benign tumors, 3 were detected. Fifteen sites of false positive in 11 malignant tumor patients and 5 sites in 6 patients with non-tumor disease were observed. Our study indicates that 99mTc-MIBI is a safe and excellent agent for the localization of tumors. Especially, the fact that 99mTc-MIBI detected remote metastatic lesions with high sensitivity is a great advantage over the other conventional imaging modalities.

We evaluated the safety and clinical usefulness of the same day protocol of exercise 99mTc-MIBI SPECT in 107 patients with heart diseases. No adverse event was observed except for one case of transient hypotension caused by the exercise. More than 95% of stress images and all of the rest images were judged as "Excellent" or "Good" in image quality. Overall sensitivity was 84.3% in detecting coronary artery disease, and no statistical difference was observed between the results obtained with Re-Ex and Ex-Re protocols. The examination was "Quite Effective" or "Effective" in diagnostic efficacy in 96.2% of the cases. We concluded that the same day protocol is a safe and useful method for diagnosing myocardial ischemia, which provides high image quality and valuable information.

The purpose of this study was to clarify the possibility of simultaneous evaluation of myocardial perfusion and fatty acid metabolism using a single injection of 123I-beta-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) in patients with acute coronary syndromes.Thirty patients with unstable angina pectoris (UAP group) and 15 patients with acute myocardial infarction (MI group) were studied. BMIPP dynamic SPECT was performed 2 min after the injection of BMIPP (185 MBq), and images were obtained every 3 min for 15 min with a three-head gamma camera. Conventional BMIPP SPECT was also performed 30 min after the injection. Serial BMIPP and resting 201TI images were compared.A 201TI-BMIPP mismatch between 30-min BMIPP and resting 201TI images was observed in 27 of 30 patients in the UAP group and 8 of 15 patients in the MI group, respectively. However, a 201TI-BMIPP mismatch between early (2-5-min) BMIPP and resting 201TI images was observed in only 2 of 30 patients in the UAP group and in only 2 of 15 patients in the MI group, respectively. The kappa statistics of tracer uptake between early BMIPP and resting 201TI images showed good concordance in UAP (kappa = 0.823) and MI (kappa = 0.765) groups, respectively. These results indicated that initial distribution of BMIPP reflects myocardial perfusion in patients with acute coronary syndromes.Myocardial perfusion and fatty acid metabolism can be evaluated simultaneously using a single injection of BMIPP, when images are taken soon (2-5 min) and long after the injection in patients with acute coronary syndromes.

Increased pulmonary 201TlCl (Tl) uptake during exercise has been used as a marker of multivessel critical stenosis. We studied whether pulmonary 99mTc-Tetrofosmin (TF) uptake measurement during exercise is useful as an additional indicator for the detection of coronary artery disease. Pulmonary to myocardial uptake ratio (P/M) measured by TF scintigraphy during exercise were compared with findings of coronary angiography in eighty one patients with ischemic heart disease and also P/M measured with Tl in twenty one cases. TF P/M level in the patients with triple vessel disease was higher than that in the patients with no coronary stenosis, single vessel disease and double vessel disease. However, there was no significant correlation between TF P/M and the severity of coronary artery stenosis. Inverse correlation was observed between TF P/M and left ventricular ejection fraction (LVEF) (r = 0.29, p0.01). TF P/M in the patients less than 50% of LVEF was significantly higher than that in the patients over 50% of LVEF (p = 0.05). TF P/M was well correlated with Tl P/M (r = 0.86). In conclusion, quantitative TF P/M during exercise was thought to be useful indicator for the evaluation of coronary artery disease.

We experienced a case of a 60 year-old man with cardiac sympathetic denervation after aortic graft replacement of ascending aorta for a dissecting aneurysm (Debakey type II). Fourteen years after pheochromocytomectomy (paraganglioma), the patient developed a severe chest pain, and admitted to the hospital for the diagnosis of dissecting aneurysm. CT scan with contrast enhancement revealed thrombosed dissecting aneurysm in the region of ascending aorta to aortic arch. Graft replacement was undergone on the same day. 123I-MIBG imaging 20 days after the operation showed severely attenuated myocardial uptake (heart to mediastinum ratio 1.19), although the MIBG imaging before the operation showed normal myocardial uptake (heart to mediastinum ratio 1.55). Heart rate variability analysis in Holter ECG showed that the power of the low frequency (LF), that of the high frequency (HF) and L/H ratio were severely decreased. MIBG and heart rate variability analysis indicated that cardiac sympathetic and parasympathetic nerve were denervated. This is the first report of cardiac sympathetic denervation after aortic vascular surgery. Clinical significance of cardiac sympathetic denervation after aortic vascular surgery is uncertain, and further investigation will be required.

The phase III clinical trial of strontium-89 chloride agent (SMS.2P) was performed in 90 patients with painful bone metastases secondary to prostate (53), breast (18) and other types of cancer (19). Some patients experienced a transient increase in pain or nausea and vomiting. However both symptoms subsided and serious side effects were not observed in any of the patients. As reported, we confirmed some abnormal changes in peripheral blood picture. A decrease in the number of white blood cells and platelets was considered to be partly a result of bone marrow suppression due to 89Sr irradiation. Pain was substantially improved after 89Sr therapy in 58% of the patients and there was some alleviation in 12%. The release from pain was accompanied by an improved quality of life for these patients including sleep patterns and morbidity. Some patients were able to resume their former life styles. Most of the improved patients experienced pain relief from days to one week following 89Sr therapy and in half cases, this remained effective for 2 or 3 months. There were even cases in which the pain relief continued over an observation period of time of clinical study.

In order to evaluate the exposure to the nuclear medicine technologists from patients who had been administrated with radiopharmaceuticals, we measured the exposure in 5 common diagnostic procedures (bone, lung, tumor scan, and brain, myocardial SPECT, n = 8 to 52) using a silicon semiconductor pocket dosimeter. We also measured the spatial dose rates at 5 cm, 50 cm, and 100 cm from skin surface of the patients (n = 10 to 21) using an ionization chamber, both 5 min after injection and right before the studies with the same procedures above. We further measured the spatial dose rate distributions around the patients in the 4 procedures (bone, renal, blood pool scan, and brain SPECT, n = 2 to 3). In results, the exposure to the technologists in each procedure was small (0.5, 0.5, 0.7, 1.6, and 0.3 muSv in each bone, lung, tumor scan, and brain, myocardial SPECT, respectively), compared with the dose limits of the medical workers. However, the dose-response relationships in cancer and hereditary effects, referred to as the stochastic effects, have been assumed linear and no threshold models; therefore, the exposure should be minimized. For this purpose, the measurements of spatial dose rates and spatial dose rate distributions were thought to be useful. The differences of these results among procedures were caused by the differences of dose distributions and physical and biological half lives of the radiopharmaceuticals. The results of the measurements in 7 consecutive weeks suggested that the direct measurement of the exposure using a high sensitive digital pocket dosimeter might result a reduced exposure to the technologists.

A series of thallium-201 (201Tl) and technetium-99m (99mTc) myocardial perfusion images with or without perfusion defects were acquired by 360 degrees arc using a triple-head camera. The vertical long, horizontal long, and short axis images of 201Tl and 99mTc with 360 degrees, 180 degrees, and opposite 180 degrees were identically reconstructed and reoriented without attenuation correction. In order to detect the detailed differences between 360 degrees (30 degrees - 390 degrees) and 180 degrees (30 degrees - 210 degrees) images, the opposite 180 degrees (210 degrees - 30 degrees) images were utilized. Opposite 180 degrees images revealed the contribution of those to the 360 degrees images. In the normal perfusion images, the CV (coefficient of variation) of the counts in 360 degrees images with 201Tl by the segments was larger than 180 degrees images. On the contrary, the CV of the counts in 360 degrees images with 99mTc was smaller than 180 degrees images. This difference, caused by the difference of photon energy, were detected mainly as the extent of counts decreasing in the deep segments in the opposite 180 degrees images. Lesion contrasts of the opposite 180 degrees images were lower than those of 180 degrees images due to distance related collimator response (the detector response of the collimated gamma camera varies with source-to-detector distance) and scatter. Therefore, lesion contrasts were more decreased in the 360 degrees images compared with those of 180 degrees images, especially in the segments of lateral and anterior walls. The differences in lesion contrasts between 201Tl and 99mTc images were mainly in the segments of inferior and posterior walls (p0.05). Lesion contrast was dependent on the location of the perfusion defects, reconstruction arc, and photon energy.

To evaluate the diagnostic accuracy of detection of angina-related coronary arteries in patients with unstable angina pectoris. Twenty patients with unstable angina pectoris underwent 123I-BMIPP scintigraphy at rest. A mean duration from last anginal attack to 123I-BMIPP scintigraphy was 408 +/- 3.2 days. Seventeen of 20 angina-related coronary territories were detected by reduced 123I-BMIPP uptake. The sensitivity and specificity for detection of angina-related coronary arteries were 85% and 95%, respectively. The decrease in myocardial uptake of 123I-BMIPP agreed with the decrease in regional wall motion by using ultrasonic echocardiography. 123I-BMIPP scintigraphy may be useful for detection of angina-related coronary artery in a routine clinical examination in patients with unstable angina pectoris.

We evaluated the clinical significance of myocardial imaging using 123I-15-(p-iodophenyl)-3-methyl pentadecanoic acid (BMIPP) scintigraphy in patients with stable effort angina pectoris (SAP) and unstable angina pectoris (UAP). Thirty-three patients with SAP were studied using rest BMIPP and stress 201TlCl (Tl) myocardial scintigraphy, and 13 patients with worsening effort type of UAP were also examined using both rest BMIPP and Tl scintigraphy. We compared those BMIPP findings with myocardial perfusion images obtained with Tl and the regional wall motion determined by left ventriculography. In 45% of 282 segments of myocardial ischemia of SAP, the degree of myocardial uptake of BMIPP was concordant with that of stress Tl and the defect score of Tl was higher than that of BMIPP. On the other hand, in 32% of 62 segments of ischemia of UAP, the degree of myocardial BMIPP and Tl uptake was concordant and BMIPP defect score was higher than Tl score. In SAP, the decrease in regional wall motion agreed better with the decrease in myocardial uptake of BMIPP than that of Tl. These results suggest that myocardial ischemic regions decreased BMIPP uptake show the disturbance of fatty acid metabolism and lead to abnormal wall motions. Such ischemic regions may be clinically severe state in patients with angina pectoris.

The purpose of this study was to clarify the clinical significance of 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy in patients with left ventricular pressure-overload diseases. MIBG scintigraphy was applied to 10 pts with aortic valve stenosis (AS group), 11 pts with hypertrophic obstructive cardiomyopathy (HOCM group), 17 pts with hypertrophic non-obstructive cardiomyopathy (HCM group) and 6 control cases (C group). Mean pressure gradient in AS and HOCM groups was 62 +/- 21 mmHg and 38 +/- 18 mmHg, respectively. Initial myocardial uptake of MIBG (MU) was higher in the AS (1.92 +/- 0.46%) and HOCM (2.27 +/- 0.47%) groups than those in the HCM (1.61 +/- 0.29%) and C (1.50 +/- 0.23) groups. Myocardial clearance of MIBG (MC) was higher in the AS (39 +/- 11%), HOCM (37 +/- 19%) and HCM (28 +/- 17%) groups than that in the C (14 +/- 6%) groups. Heart/mediastinum count ratio (H/M) of AS, HOCM, HCM and C groups was 1.87 +/- 0.29, 2.09 +/- 0.19, 1.98 +/- 0.26, and 2.20 +/- 0.10, respectively. In the cases of AS, positive correlation was observed between mean pressure gradient and MU (r = 0.618, p0.05). In conclusion, MU was increased in the case of left ventricular pressure-overload state (AS and HOCM).

The purpose of this study was to clarify the diagnostic value of identifying viable myocardium using 99mTc-Tetrofosmin scintigraphy. Twenty-one patients with chronic coronary artery disease were studied using 201Tl exercise myocardial scintigraphy with reinjection and 99mTc-Tetrofosmin exercise myocardial scintigraphy. All patients had a history of old myocardial infarction. For 99mTc-Tetrofosmin scintigraphy, 222 MBq of 99mTc-Tetrofosmin was injected during exercise, and exercise images were obtained 20 min thereafter. There hours later, 666 MBq of 99mTc-Tetrofosmin was injected at rest, and images were obtained 40 min and 220 min later. Myocardial viability in the 99mTc-Tetrofosmin scintigraphy was estimated as fill-in findings (FF) or over 50% of %RI uptake (%TF) in the rest image. Myocardial viability in the 201Tl scintigraphy was estimated as redistribution (RD), fill-in findings in the reinjection image (FR) or over 50% of %RI uptake in the reinjection image (% TL). Sixteen of the 21 patients (76%) who underwent 201Tl scintigraphy (RD 10, FR 3, %TL 3 cases) and 15 of the 21 patients (71%) who underwent 99mTc-Tetrofosmin scintigraphy (FF 11, %TF 4 cases) had viable myocardium in the infarcted area. A comparison between the 99mTc-Tetrofosmin rest images obtained 40 min after the injection and that of 220 min revealed no redistribution findings. The %RI uptake of the infarcted area in the resting 99mTc-Tetrofosmin image (47 +/- 16%) was slightly lower than that in the 201Tl reinjection image (52 +/- 16%). In conclusion, viable myocardium was as clearly identified by 99mTc-Tetrofosmin, as by 201Tl scintigraphy.

We have often experienced false positive results of the stress Thallium-201 myocardial scintigraphy (TL) for the evaluation of artery bypass graft patency after coronary artery bypass surgery (CABG). The purpose of this study is to clarify the frequency and the clinical significance of this findings. Sixty-two patients undergoing coronary angiography (CAG) after CABG were studied. These patients had undergone at total of 156 bypasses (artery grafts 108, saphenous vein grafts 48, mean bypass grafts number 2.65/cases), and the mean period from CABG to TL was 41.6 +/- 34 days. The territories of stress induced ischemia were divided into 3 territories; left anterior descending (LAD), right coronary artery (RCA), and left circumflex (LCX) territories. Patency of the bypass grafts was estimated on the absence of transient perfusion defect (TPD) on TL images. The incidence of false positive results was higher in Dipyridamole TL (38%) than in Exercise TL (18%) and higher in LAD territories (38%) than in RCA (11%) and LCX (13%) territories. All false positive cases showed no evidence of chest pain and significant ST-T change during stress TL test. High incidence of false positive results of stress TL test was observed for the evaluation of artery bypass graft patency after CABG.

Two cases diagnosed dilated cardiomyopathy received beta-blocker therapy, and underwent 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy before and after the treatment. In case 1, symptoms and cardiac function were improved in 1 month and 4 months after the treatment (LVEF increased from 19% to 32% and 40%), and myocardial clearance of MIBG decreased from 50% to 27% and 29%. In case 2, both symptoms and cardiac function were not improved in 1 month and 3 months after the treatment (LVEF was changed from 11% to 10% and 13%), and myocardial clearance was not significantly different between before (50%) and after (1 month: 46%, 3 months: 50%) the treatment. It was indicated that myocardial clearance of MIBG might depend on the extent of the improvement of cardiac function and symptoms, and might reflect the effects of beta-blocker therapy.

Discordant findings of inferior MIBG defect between SPECT and planar images were sometimes observed in the clinical studies. In this study, we compared inferior myocardial findings between planar and SPECT image of 123I-metaiodobenzyl-guanidine (MIBG) cardiac scintigraphy in 29 patients. All patients were estimated as normal in anterior accumulation of MIBG. The patients were divided into 3 groups according to the visual finding of inferior defect in the planar and SPECT image; normal group (normal inferior accumulation of MIBG both in the planar and SPECT image, N = 10), discordance group (inferior MIBG defect was only observed in the SPECT image, but was not observed in the planar image, N = 7), inferior defect group (inferior MIBG defect was observed both in the planar and SPECT image, N = 12). Inferior/anterior count ratio of SPECT and planar image were 0.96 +/- 0.11 vs. 0.97 +/- 0.05 in normal group, 0.59 +/- 0.21 vs. 0.99 +/- 0.13 in discordance group, 0.46 +/- 0.13 vs. 0.82 +/- 0.04 in inferior defect group. Liver/heart count ratio was significantly higher in the discordance group (2.07 +/- 0.49) than that in the normal (1.14 +/- 0.15) and inferior defect group (1.45 +/- 0.39). In phantom study, it has been reported that increased liver accumulation of MIBG causes artifactual inferior defect adjacent to the liver. These data indicate that increased liver/heart count ratio may cause artifactual inferior defect on MIBG SPECT image in the clinical studies. Planar image evaluation may be helpful to distinct the artifactual inferior defect on SPECT image.

The purpose of this study is to clarify whether dynamic SPECT (DECT) immediately after the injection of 123I-15-(p-iodophenyl)-3-methyl pentadecanoic acid (BMIPP) may represent myocardial perfusion imaging. Ten patients with unstable angina pectoris (UAP), 11 patients with acute myocardial infarction (AMI) and 6 patients with non-ischemic heart disease (NIHD) were studied using BMIPP myocardial scintigraphy with DECT. DECT acquisition was started 2 minutes after the injection of BMIPP, and DECT images were obtained every three minute for 15 minutes with 3-headed gamma camera SPECT system. Additionally, static SPECT images were acquired 30 minutes after the injection of BMIPP. These SPECT images of BMIPP were compared with thallium-201 myocardial perfusion images at rest. In UAP group, early DECT images showed almost the same findings as thallium-201 images in 8 of 10 patients, and SPECT images at 30 minutes after the injection showed reduced accumulation of BMIPP compared with thallium-201 images in all patients. In AMI group, early DECT images showed the same findings as thallium-201 perfusion images in 9 of 11 patients, and SPECT images at 30 minutes after the injection showed reduced accumulation of BMIPP compared with thallium-201 images in 5 of 11 patients. These results indicate that myocardial perfusion can be evaluated in the early image using DECT, in addition to myocardial fatty acid metabolism in the delayed image.

The therapeutic response of 131I-MIBG was evaluated in 4 patients with malignant pheochromocytoma who had been treated with 131I-MIBG and followed-up over 5 years. The patients were 2 men and 2 women with ages ranging from 41 to 69 years old (mean 53 years). The primary tumors in 3 of 4 patients had been resected four to eight years before 131I-MIBG treatment. One patient was diagnosed as adrenal pheochromocytoma, and two were retroperitoneal paraganglioma. And in one patient, the resection of primary mediastinal tumor was not performed due to the adhesion to pericardium but the diagnosis of paraganglioma was obtained by biopsy of bone lesion. All patients showed the clear accumulation of 131I-MIBG in tumor on scintigraphy. The number of doses of 131I-MIBG ranged from one to three times with 3.7 GBq per administration and a cumulative activity from 3.7 to 11.1 GBq. Treatment effect was obvious in one patient with lung, bone, and lymph node metastases whose cumulated absorbed dose with 11.1 GBq of 131I-MIBG exceeded over 150 Gy. At the present time, the duration of survival since the beginning of initial 131I-MIBG therapy is over 5 yrs. The other three patients, however, showed little effects, and died with the disease in 2.6 to 4.1 years after the initial 131I-MIBG therapy. 131I-MIBG will become a promising agent for therapy in patients with malignant pheochromocytoma with high degree of accumulation.

We studied initial myocardial uptake and myocardial clearance of 123I-metaiodobenzylguanidine (MIBG) in patients with ischemic heart disease of left ventricular dysfunction and dilated cardiomyopathy. Eleven patients with ischemic heart disease of left ventricular dysfunction (IHD group), 6 patients with dilated cardiomyopathy (DCM group) and 7 control cases (control group) were studied. Heart to mediastinum activity ratio (H/M) of early and delayed image was significantly lower in the IHD and DCM groups than in the control group. Although initial myocardial uptake of MIBG showed no significant difference among three groups, myocardial clearance of MIBG was significantly higher in the IHD (35 +/- 11%) and DCM (48 +/- 13%) groups than that in the control group (19 +/- 10%). H/M of delayed image was related to the left ventricular size, initial MIBG uptake and MIBG myocardial clearance. Negative correlation was observed between MIBG myocardial clearance and left ventricular ejection fraction in all cases. In conclusion, initial myocardial uptake of MIBG were not decreased in patients with IHD and DCM. Enhanced myocardial clearance of MIBG was observed not only in patients with DCM but also in patients with IHD.

To investigate the effect of ACTH on thyroid function, thyroid hormone levels were measured in twelve patients with epileptic children who were treated with ACTH. One week after daily administration of ACTH, serum T3, T4, TSH, thyroglobulin and T3/T4 ratio showed significantly lower values compared with those of pretreatment values (p0.001-p0.05). Thyroid hormone levels respectively showed negative correlation with cortisol levels before and one week after ACTH treatment respectively. Tapering of ACTH brought a rapid recovery of T3, T4, TSH and thyroglobulin levels with concomitant return of plasma cortisol levels to the normal range. These results suggested that excess ACTH suppressed thyroid hormone secretion mainly through a decreased TSH secretion and a peripheral conversion of T4 to T3 by increased cortisol levels.

Discordance between planar and SPECT image of inferior myocardial defect on 123I-metaiodobenzylguanidine myocardial scintigraphy (MIBG) was occasionally observed in the clinical studies. The purpose of this study is to clarify the existence of artifactual myocardial defect on MIBG SPECT image. Phantom study was performed in various kinds of situation using triple gamma camera. Artifactual defect adjacent to the liver was significantly observed in the case of increased liver/heart uptake ratio more than 2:1. Artifactual defect was markedly observed in the 180 degrees than that in the 360 degrees SPECT acquisition. To avoid artifactual defect during SPECT acquisition, liver phantom was moved down to the foot direction (vanishing liver position). In this phantom position, artifactual defect adjacent to the liver was not observed on reconstructed myocardial SPECT image. The vanishing liver position was also applicable to human study. Human body was inclined to right side at an angle of 15 degrees, artifactual defect could be avoided. Further study is needed to analyze the cause of this artifactual defect and to conform the preventive method with vanishing liver position in the routine myocardial SPECT examination.

The fractional uptake of intact monoclonal antibodies by tumors is relatively low. Various methods to alter the molecular structure have been used to augment tumor uptake. These chemical manipulations, however, may alter the specificity of antibody binding.Comparative studies of biodistribution, radioimmunoimaging and macroautoradiography in LC-6 xenografted mice were conducted with the 125I-labeled intact and N-terminal deglycosylated monoclonal antibodies to evaluate the effect on deglycosylation on antibody binding.The removal of N-glycosyl residues from this monoclonal antibody significantly enhanced specific localization of the radioactivity to the tumor, especially to its necrotic fraction. Nonspecific accumulation of radioactivity to the necrotic fraction of the tumor was excluded by biodistribution studies demonstrating selective accumulation of 125I-labeled monoclonal antibody after coadministration of 125I-monoclonal antibody (intact or N-deglycosylated) with 131I-labeled control IgM.The lung cancer-associated human monoclonal antibody HB4C5, which recognizes histone H2B as the antigen, accumulates specifically to the necrotic fraction of tumor. The uptake is enhanced by removal of N-terminal glycosyl residues from the antigen-binding site of the light chain.

Hybridomas producing human monoclonal antibodies (h-MoAbs) were generated by using lymphocytes of the regional lymph node from cancer patients or peripheral blood lymphocytes (PBL) from healthy volunteers which were immunized in vitro. The h-MoAbs thus obtained were applied to a wide range of clinical purposes, including the immunocytological detection of cancer cells in sputum, the radioimmunoimaging of lung cancer and the therapies of tetanus and cancer. Cancer cells in sputum can be simply detected by the immunostaining method using h-MoAb AE-6. Clear images of lung cancer xenografts in nude mice were obtained with 125I-labeled h-MoAb HB4C5. Tetanus was successfully cured by the use of a combination of h-MoAbs G2 and G6 in animal tests. Cancer xenografts in nude mice were regressed by the administration of h-MoAb S-97 conjugated with Pseudomonas exotoxin A (PE). These data indicate that h-MoAbs are clinically of potent value.

Clinical utility for detection of hyperfunctioning parathyroid glands in patients with primary and secondary hyperparathyroidism (PHPT, SHPT) using 201TlCl and 99mTcO4-images was estimated in 50 patients including 18 PHPT and 32 SHPT (male; n = 31, female; n = 19, 51.5 +/- 11.1 yr). Detection of 94 hyperfunctioning parathyroid glands in 34 cases were achieved correctly by 201TlCl and 99mTcO4- images in agreement with surgical findings. Detectability of hyperfunctioning parathyroid glands was 100% in more than 1.0 g, 62.0% in more than 0.5 g and 41.5% in less than 0.5 g respectively. Ectopic parathyroid glands in two cases and a metastasis to pretracheal lymph node in one case were clearly demonstrated. Our results show that parathyroid scintigraphy using 201TlCl and 99mTcO4- as well as 131I or 123I is useful and safe method for preoperative detection of hyperfunctioning parathyroid glands.