Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus-the 'D-shuttle' project

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter 'D-shuttle' for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the terrestrial background radiation level of other regions/countries.

Multitensor tractography enables better depiction of motor pathways: initial clinical experience using diffusion-weighted MR imaging with standard b-value

BACKGROUND AND PURPOSE

The purpose of this work was to test the feasibility of using high angular resolution diffusion imaging (HARDI)-based multitensor tractography to depict motor pathways in patients with brain tumors.

MATERIALS AND METHODS

Ten patients (6 males and 4 females) with a mean age of 52 years (range, 9-77 years) were scanned using a 1.5T clinical MR unit. Single-shot echo-planar imaging was used for diffusion-weighted imaging (repetition time, 6000 ms; excitation time, 88 ms) with a diffusion-sensitizing gradient in 32 orientations and a b-value of 1000 s/mm(2). Data postprocessing was performed using both the conventional single- and multitensor methods. The depiction rate of the 5 major components of the motor pathways, that is, the lower extremity, trunk, hand, face, and tongue, was assessed.

RESULTS

Motor fibers on both lesional and contralesional sides were successfully depicted by both the single-tensor and multitensor techniques. However, with the single-tensor model, the depiction of motor pathways was typically limited to the fibers of trunk areas. With the multitensor technique, at least 4 of 5 major fiber bundles arising from the primary motor cortex could be identified.

CONCLUSION

HARDI-based multitensor tractography using a standard b-value (1000 s/mm(2)) can depict the fiber tracts from the face and tongue regions of the primary motor cortex.

Diffusion anisotropy measurement of brain white matter is affected by voxel size: underestimation occurs in areas with crossing fibers

BACKGROUND AND PURPOSE

Voxel size/shape of diffusion tensor imaging (DTI) may directly affect the measurement of fractional anisotropy (FA) in regions where there are crossing fibers. The purpose of this article was to investigate the effect of voxel size/shape on measured FA by using isotropic and nonisotropic voxels.

MATERIALS AND METHODS

Ten healthy adult volunteers had MR imaging by using a 1.5 T clinical imager. DTI was performed with 2 different voxel sizes: a 2-mm-section isotropic voxel (2 x 2 x 2 mm(3)) and a 6-mm-section nonisotropic voxel (2 x 2 x 6 mm(3)). Images were obtained by using a single-shot echo-planar imaging technique with motion-probing gradients in 15 orientations and a b-value of 1000 s/mm(2). FA and the apparent diffusion coefficient (ADC) were measured at different sites of the brain.

RESULTS

When smaller isotropic voxels were used, the FA was greater in areas with crossing fibers, including the superior longitudinal fasciculus, the thalamus, and the red nucleus; the FA was not significantly different in areas without crossing fibers, such as the corpus callosum, the posterior limb of the internal capsule, and the corticospinal tract at the level of the centrum semiovale (P>.05). The ADC values were not affected by voxel size/shape at any of the areas of the brain that were measured.

CONCLUSION

FA values that are measured in regions containing crossing fibers are underestimated when using nonisotropic DTI.

[A case of localized pleural mesothelioma]

Localized pleural mesothelioma is reported. A 62-year-old male had been observed as a patient with old tuberculosis of the left lung for a few decades. For detailed examination of fever of unknown cause and abnormal shadow on the chest X-ray, the patient was introduced to our hospital. By percutaneous cytodiagnosis, the illness was diagnosed as pleural mesothelioma, and the patient underwent surgery. Since adhesion of the tumor to the lower lobe of the lung was extremely tight, the tumor and the left lower lobe were resected as a mass. The tumor was about 15 cm in diameter, weighed 1,300 g and a slight pleural effusion was observed. The tumor was diagnosed as malignant localized pleural mesothelioma pathologically. Localized pleural mesothelioma should be subjected to surgery in the early stage, in principle. Even in cases difficult to diagnose, operation should not be delayed by repeating easy-going needle-biopsy or a long-term treatment with antitubercular drugs. The postoperative course of this case has been good, and no recurrence nor metastasis has been detected.

[Complete response of lung metastasis from bladder cancer by combination chemotherapy with methotrexate, epirubicin and cisplatin: a case report]

We report a case of lung metastasis from bladder cancer effectively responding to a combination chemotherapy using methotrexate, epirubicin and cisplatin (MEC therapy). A 78-year-old man with high grade bladder cancer underwent total cystectomy on June 5, 1991. He was pointed out to have an abnormal shadow on the plain chest X-ray on August 14, 1992. Computed tomography demonstrated multiple lung metastasis. MEC combination chemotherapy was applied for this case. After 3 courses of MEC therapy, computed tomography showed marked regression of tumor. He has been alive for 12 months with no evidence of disease after chemotherapy. Toxicity of MEC therapy were moderate myelosuppression and mild anorexia and alopecia. These toxicity was adequately tolerable by the 78-year-old patient. This case suggests that MEC therapy is effective against advanced bladder cancer.

Pleural multicystic mesothelial proliferation

We report a rare case of pleural multicystic mesothelial proliferation occurring in a 62-year-old Japanese woman. Macroscopically, the lesion consisted of multiple thin wall cysts containing clear serous fluid. Histologic studies, including hematoxin-eosin stain, as well as the immunohistochemical method, revealed that the lesion was mesothelial in origin and consistent with a reactive change.

[The changes of human plasma ACTH and immunoreactive beta-endorphin during spontaneous or oxytocics induced/maintained labor and delivery (author's transl)]

To evaluate the effects of oxytocics on ACTH and Immunoreactive (IR)-beta-endorphin release, concentrations of these hormones in the plasma of 22 women during spontaneous labor, 22 women in labor who had received oxytocin and 19 women in labor who had received PG.F2 alpha at the time of vaginal delivery, were measured. Maternal ACTH and IR-beta-endorphin concentrations were elevated during spontaneous or oxytocics induced/maintained labor and peaked immediately after delivery and decreased two hours later. There were significant correlations between ACTH and IR-beta-endorphin concentrations during spontaneous labor and delivery (r = 0.921, p less than 0.0001), as well as in oxytocin or PG.F2 alpha induced/maintained labor and delivery (r = 0.833, r = 0.916, p less than 0.0001, respectively). The concentrations of ACTH and IR-beta-endorphin during PG-F2 alpha infusion were slightly higher than those seen in the other two types of labor. However, there was no significant difference in the levels of ACTH and IR-beta-endorphin among the three types of labor. Simultaneous maternal and umbilical cord plasma samples were obtained in 25 cases at delivery. However, there was no significant correlation between ACTH or IR-beta-endorphin concentrations in paired samples. These results suggest that 1) IR-beta-endorphin is secreted in parallel with ACTH, into the peripheral blood by the maternal pituitary gland in response to the stress of labor during all types of labor and delivery; 2) there is no significant difference in the response of ACTH and IR-beta-endorphin between spontaneous and oxytocics induced/maintained labor and delivery: 3) ACTH and IR-beta-endorphin in cord blood are not of maternal origin.

[The changes of human plasma ACTH, immunoreactive-beta-endorphin and cortisol during pregnancy, labor and delivery (author's transl)]

Immunoreactive (IR)-beta-endorphin, ACTH and cortisol from the plasma of 88 pregnant women during gestation, and 28 women with spontaneous labor were measured. The concentrations of ACTH, IR-beta-endorphin and cortisol gradually increased during gestation. There were significant correlation between ACTH and IR-beta-endorphin (r = 0.79, p less than 0.0001), as well as between ACTH and cortisol (r = 0.54, p less than 0.0001) during gestation. Maternal ACTH and IR-beta-endorphin concentrations rapidly increased during the course of labor, peaked immediately after delivery at 671.3 +/- 136.1 and 513.9 +/- 85.5 pg/ml, respectively, and then decreased two hours later. There was a highly significant correlation (r = 0.89, p less than 0.0001) between ACTH and IR-beta-endorphin during labor. The levels of cortisol were elevated during labor and showed no difference during labor, or two hours later. However, there was no significant relationship between ACTH and cortisol (r = 0.24) during labor. Chromatographic analysis was performed on the pooled plasma extracts from pregnant women at the various stage of labor. In ACTH analysis, a single peak was seen at the position of native ACTH in each case. All detectable immunoreactivities eluted in two peaks at the position of beta-LPH and beta-endorphin. However, beta-LPH to beta-endorphin ratio was almost the same in each case. These results suggest that 1) ACTH and IR-beta-endorphin are secreted concomitantly, probably by the maternal pituitary gland during gestation as well as in response to the stress of labor; 2) the lack of correlation between ACTH and cortisol is due to the difference in metabolic clearance rate of these hormones during labor; 3) neither peripheral nor intrapituitary conversion of beta-LPH to beta-endorphin is seen during gestation and labor.

Prolactin directly inhibits basal as well as gonadotropin-stimulated secretion of progesterone and 17 beta-estradiol in the human ovary

An ovarian perifusion technique was used to determine if there is a direct suppressive effect of PRL on human gonadal steroid secretion. Ovarian tissue from nine patients was examined. Ovine PRL (0.1-10 IU/ml) directly suppressed progesterone and 17 beta-estradiol secretion by human ovaries. hCG (1-10 IU/ml) stimulated both progesterone and 17 beta-estradiol secretion. Simultaneous administration of PRL (5-10 IU/ml) suppressed the stimulatory effect of hCG. The ovarian tissue obtained from a hyperprolactinemic patient did not respond to hCG. These results indicate that PRL inhibits both basal and gonadotropin-stimulated ovarian steroid secretion by human ovaries and that this may be one cause of the hypogonadism associated with hyperprolactinemia.

Placental secretion of prolactin, ACTH and immunoreactive beta-endorphin during pregnancy

The placental secretion of Prl, ACTH and immunoreactive (IR)-beta-endorphin were examined in early and later pregnancy with a perfusion method and by determining tissue concentrations of these hormones. Prl was secreted mainly from decidual tissue during 5-6 h long perfusions. Tissue concentrations of Prl were also significantly higher in decidual than in trophoblastic tissue. In contrast, the tissue concentrations of hCG, hPL, ACTH and IR-beta-endorphin were significantly higher in decidual than in trophoblastic tissues. In contrast, the tissue concentrations of hCG, hPL, ACTH and IR-beta-endorphin were significantly higher in trophoblastic than in decidual tissues. Production of hCG and hPL was predominantly demonstrated in trophoblastic tissues by the perfusion method but ACTH and IR-beta-endorphin were too low to be detected by perfusion.