Dental hygiene education in Japan: present status and future directions.

The aim of this report is to provide basic information about the historical development, current status and future needs of education and training of dental hygienists in Japan. The first formal training of dental hygienists in Japan started at Tokyo in 1949. Restructure and modification of the dental hygiene education system has been reiterated over the years in order to satisfy the needs of the constantly changing society. Although previously only vocational training was provided for dental hygienists, higher-level education has been conducted. The present legislation of dental hygiene has gone through a complicated process. The student should take the dental hygienist licensing examination which is held once a year by the National Board organized by the Ministry of Health, Labour and Welfare. Currently there are 136 dental hygiene schools and the total enrolment is about 7000. The duration of dental hygiene education course has been prolonged from 2 to 3 years since 2001. In 2004, the 4-year course started. The 2-year dental hygiene education program is expected to be replaced with the 3- and 4-year courses by 2010. The dental hygiene education system in Japan will be improved in many ways as dental hygienists are expected to participate in health promotion and preventive care, and to gain knowledge of the economics and organization of health care in relation to oral hygiene.

Assessment of myocardial viability with a positron coincidence gamma camera using fluorodeoxyglucose in comparison with dedicated PET.

The use of dual-head gamma camera modified positron coincidence detection (PCD) is a new, alternative method of 2-[18F]fluoro-2-deoxy-D-glucose (FDG) imaging. This study investigated the potential ability of evaluating myocardial viability in patients with ischaemic heart disease by FDG imaging using PCD. A total of 21 patients (18 male, three female; mean age 59.7+/-8.5 years) with a history of previous myocardial infarction and confirmed coronary angiography underwent FDG PCD and FDG PET after oral glucose loading (75 g). Quantitative analysis was compared between images of FDG PCD and FDG PET. A significant linear correlation between the segmental percentage of FDG uptake obtained by PCD and PET was observed (r=0.63, P<0.001). By receiver operating characteristic (ROC) analysis, using FDG PET as the 'gold standard', at the 50% threshold value in PET, FDG PCD showed a sensitivity of 92% and specificity of 63% in detecting myocardial viability. Regional analysis showed lower agreement of FDG PCD and FDG PET in the inferior (79%) and septal (70%) walls compared with the other walls. Quantitative evaluation of myocardial viability using FDG PCD yielded comparable clinical results in apex, anterior and lateral walls to that of FDG PET. However, the agreement was lower in the inferior and septal walls. Therefore, results of FDG PCD should be carefully interpreted in evaluating myocardial viability in the inferior and septal walls. The application of a measured attenuation correction and scatter correction are needed to improve the detectability of myocardial viability in FDG imaging by coincidence gamma camera.

Radiographic assessment of scapular rotational tilt in chronic shoulder impingement syndrome.

This study presents an objective evaluation of both scapular upward and axial rotational tilts in shoulder impingement syndrome, using a scapular spine line defined on antero-posterior (AP) radiographs of the shoulder as the referential line. Twenty-seven patients with unilateral shoulder motion pain, who were diagnosed as having chronic shoulder impingement syndrome, were enrolled in the study. Scapular upward and axial rotational tilts were compared between the affected and contralateral shoulders. AP radiographs were obtained at shoulder abduction angles of 0 degrees, 45 degrees, and 90 degrees, and the X-ray films were digitized by computer. The upward and axial rotational tilts of the scapula were then evaluated on the digital images. In shoulder impingement syndrome, both upward and axial external rotations of the scapula were impaired at the painful arc angle of abduction. This tended to be more apparent for the axial rotation of the scapula than for the upward rotation. These reductions in scapular rotations reduce available clearance for the rotator cuff and humeral greater tuberosity as the shoulder is abducted.

The role of whole-body FDG-PET in preoperative assessment of tumor staging in oral cancers.

OBJECTIVE: The aim of this study is to clarify the clinical utility of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET) in determining the TNM classification in patients with oral cancer. METHODS: Twenty-five consecutive patients (14 male and 11 female; age range, 40 yr to 86 yr) with oral cancer were included in this study. The diagnostic accuracy for detecting cervical lymph nodes was investigated by comparing the results of CT and/or MRI and physical findings. For the semi-quantitative analysis, the tumor standardized uptake value (SUV) and tumor to background SUV ratio (T/B ratio) were assessed in primary tumors and cervical lymph nodes. RESULTS: All primary lesions were visualized on FDG-PET images. Even though artifacts from dental materials near the lesion hampered the delineation of primary tumors on CT/MRI, the extent of primary tumors was accurately assessed by FDG-PET. The SUV and T/B ratio in the primary tumor classified in higher T grade (T3 and T4) was significantly higher than that in lower T grade (T1 and T2) (mean +/- SD of SUV; 8.32 +/- 2.99 vs. 5.15 +/- 3.77, p < 0.01, mean +/- SD of T/B ratio; 6.96 +/- 3.23 vs. 3.61 +/- 2.76, p < 0.01). The SUV and T/B ratio of metastatic lymph nodes were also significantly higher than those of normal lymph nodes (mean +/- SD of SUV; 3.39 +/- 1.69 vs. 1.55 +/- 0.57, p < 0.001, mean +/- SD of T/B ratio; 2.46 +/- 1.08 vs. 1.03 +/- 0.22, p < 0.001). Among these three methods, FDG-PET in conjunction with CT/MRI showed the highest accuracy of 92%, but there were no significant differences in diagnostic accuracy among the three methods. For the semi-quantitative analysis, a threshold SUV of 2.0 provided 100% sensitivity, 82% specificity, and 88% accuracy. Furthermore, a threshold T/B ratio of 1.5 provided 100% sensitivity, 100% specificity, and 100% accuracy. Regarding the detection of distant metastasis, there was one positive result in FDG-PET showing distant pulmonary metastasis. CONCLUSIONS: Whole-body FDG-PET is an effective and convenient diagnostic tool for the evaluation of tumor staging in patients with oral cancer. Tumor staging by whole-body FDG-PET may, in fact, supplement the conventional staging by means of CT/MRI and physical findings.

Effects of Different Types of Disparity Cues on the Response of Axis-orientation Selective Cells in the Monkey Parietal Cortex.

Purpose: To specify the cues for the discrimination of orientation in depth in axis orientation selective (AOS) neurons.Method: We analyzed the responses of AOS neurons in the monkey caudal intraparietal sulcus (cIPS) region using binocular disparity stimuli generated by stereoscopic 3 D computer graphics.Result: Most AOS neurons (20/27) were sensitive to binocular disparity and showed tuning to the orientation of a slit in the sagittal plane with orientation disparity cues. For 12 neurons we also used an array of discs or dots instead of slits to eliminate orientation disparity. Half of the neurons (6/12) responded better to the slits than to the discs or dots, suggesting that they were sensitive to orientation disparity. Five neurons (5/12) responded equally well to the discs or dots suggesting that they were more sensitive to the gradient of horizontal disparity than to the orientation disparity.Conclusion: Both orientation disparity and disparity gradient were likely to be integrated in the cIPS area to represent axis orientation of an object in space.

In vivo electron spin resonance assessment of decay constant of nitroxyl radical in selenium-deficient rat.

In vivo reducing capacity and cytosolic glutathione peroxidase (GSH-Px) activity in liver homogenate were evaluated in 6 weeks old Se-deficient and normal rats. GSH-Px was significantly lower in Se-deficient rats than in normal rats. In vivo reducing capacity in head and liver parts, estimated from in vivo signal decay of a nitroxyl spin probe using a low frequency (300 MHz) ESR spectrometer, was significantly decreased in Se-deficient rats, suggesting a decrease of antioxidant capacity in Se-deficient rats.

Assessment of fatty acid uptake in ischemic heart disease without myocardial infarction.

UNLABELLED: To assess the clinical value of 123I fatty acid analog, 123I-beta-methyl iodophenyl pentadecanoic acid (BMIPP) was imaged at rest in coronary patients without prior myocardial infarction. The BMIPP findings were compared with various clinical parameters. METHODS: Thirty-one patients with ischemic heart disease (19 with unstable angina, 12 with stable angina), without myocardial infarction underwent BMIPP SPECT at rest, coronary arteriography, rest/stress thallium SPECT and left ventriculography exams. RESULTS: Regional decrease of BMIPP was seen in 63% of the myocardial areas at risk, whereas regional perfusion decrease at rest was observed only in 35% (p < 0.01). The BMIPP decrease was more often seen in the unstable group (79%) than stable group (38%) (p < 0.01). Stress-induced ischemia was seen in 77% of segments with decreased BMIPP uptake in unstable group and in 57% in the stable group. Frequency and severity of BMIPP abnormality increased with the severity of stress-induced ischemia (p < 0.005) and the severity of coronary artery stenosis (p < 0.005). In addition, regional BMIPP abnormality was related to severity of wall motion abnormalities (p < 0.005). While 67% of segments with a wall motion abnormality showed BMIPP decrease, 36% with normal wall motion also showed BMIPP decrease (p < 0.01). CONCLUSION: Abnormal fatty acid metabolism was often observed at rest in patients with ischemic heart disease without history of myocardial infarction, and the abnormalities were related to severe myocardial ischemia and regional wall motion abnormalities.

[Assessment of clinical utility of 111In-DTPA-IgG scintigraphy in the detection of inflammation/infection--a report of multicenter phase II clinical trials].

A Phase II clinical study was performed in patients with strongly suspected focal sites of inflammation/infection to investigate clinical utility of 111In-DTPA-IgG. Neither adverse effects nor abnormal laboratory changes were noted in the all cases. Out of 59 patients, the clinical utility was evaluated in 56 patients with a total of 67 suspicious sites (19 in thorax, 13 in abdomen and pelvis, 30 in musculoskeletal system, and 5 in other regions). True positive results were obtained in 100% of lesions in the thorax (13/13) and the musculoskeletal system (26/26). There were three false negative and five false positive results. Overall sensitivity and specificity was 94.0% and 70.6%, respectively. Most of the true positive scintigram with the best image quality was acquired at Day 1 or Day 2 post-injection. A dose of 80 MBq was considered to be a practical dose for imaging. Our study indicates that 111In-DTPA-IgG is a safe and promising imaging agent for the detection of inflammation/infection, and that it is reasonable to proceed with Phase III studies to further evaluate clinical utility of the agent.

[The assessment of clinical usefulness of 131I-MIBG scintigraphy for localization of tumors of sympathetic and adrenomedullary origin--a report of multicenter phase III clinical trials].

A phase III clinical study of 131I-metaiodobenzylguanidine (131I-MIBG) was performed in 66 patients with tumors of sympathetic and adrenomedullary origin, including 32 patients with suspected pheochromocytoma, 25 with suspected neuroblastoma, 7 pre- or postoperative medullary carcinoma of the thyroid and each with carcinoid and suspected Sipple's syndrome. A total of 150 sites which were confirmed for presence (72 sites) or absence (78 sites) of tumors were examined on 131I-MIBG scintigrams. True positive ratio of the scintigraphy was 84.7% (61/72) and true negative ratio was 94.9% (74/78). Positive scintigraphy was obtained in 86.5% (32/37) of pheochromocytoma, 78.6% (22/28) of neuroblastoma and 100% (6/6) of medullary carcinoma of the thyroid. Accumulation of 131I-MIBG was seen in 16.8% of normal adrenal glands. Neither adverse reactions nor abnormal laboratory findings were noted in relation to 131I-MIBG injections. Our study indicates that 131I-MIBG is a safe and clinically useful radiotracers for the visualization and localization of tumors of sympathetic and adrenomedullary origin.

Effect of chronic administration of phenobarbital on the hepatobiliary transport of phenol red: assessment by statistical moment analysis.

The effect of enzyme induction on the hepatobiliary transport of phenol red (PR) in rats was investigated by application of a new analytical system to determine local drug disposition based on statistical moment theory (T. Kakutani et al., J. Pharmacokin. Biopharm. 13:609-631, 1985). Employing the moment parameters obtained from the time courses of plasma and biliary concentrations of PR and its metabolite after intravenous injection, the hepatobiliary transport of PR was theoretically assessed by separating it into component subprocesses such as hepatic uptake, hepatobiliary transfer, and intrahepatic metabolism. The results demonstrated that the acceleration of plasma disappearance of PR caused by pretreatment with phenobarbital (PB), known to induce hepatic enzyme systems, could be attributed to elevation of both hepatic and extrahepatic clearances. While PB did cause bile flow elevation (choleresis) and increased metabolism, these effects were shown to make little contribution to accelerated plasma disappearance of PR, since it was shown that the hepatobiliary excretion of PR was rate-limited by the intrahepatic transfer process, which was unaffected by PB treatment. From the results of this study, this experimental/analysis methodology seems to be useful in obtaining detailed information about hepatobiliary transport of the drug from in vivo data.

[Clinical trial of 111In-antimyosin antibody imaging: (1). Assessment of tracer kinetics and imaging time].

The human clinical trial of 111In-antimyosin antibody was performed in 20 patients with various cardiac disorders to assess its safety and tracer kinetics and to determine the optimal imaging time. There were no side effects derived from this tracer after its administration. The skin test and the antimurine antibody were both negative in any patient. The radiation dose to the kidney (3.6 rad) and to the whole body (0.36 rad) was acceptable. The half life of the blood clearance was 6.3 hours (fast component) and 25.8 hours (slow component) with the relatively high retention of blood activity at 24 hours (21%) and at 48 hours (11%). The planar images at 24 hours after the tracer administration in 4 patients showed high residual blood-pool activity without delineating significant myocardial uptake, while the images at 48 hours clearly demonstrated the presence or absence of discrete myocardial uptake. However, 2 patients showed significant residual blood-pool activity at 48 hours after the injection which needed 72 hour delayed scan in order to identify the myocardial uptake. In one patient, the single-photon tomography (SPECT) was useful to delineate the myocardial uptake from the residual blood-pool activity at 48 hours after the injection. Although this tracer provides an elegant technique for identifying myocardial necrosis, it needs 48 hours delayed scan and/or SPECT imaging because of relatively slow blood clearance.