RELATIONSHIP BETWEEN SOIL-SOIL-SOLUTION DISTRIBUTION COEFFICIENTS OF 125I AND 127I IN PASTURE SOIL.

We measured the depth profiles of soil-soil-solution distribution coefficients (Kd) of native 127I (127I-Kd) and exogenous 125I- (125I-Kd) in soils from a pasture near the spent nuclear fuel reprocessing plant in Rokkasho, Japan, and investigated their relationships to depth profiles of the concentration in soil of 127I and organic C and Kd of organic C (C-Kd). The depth profiles of 125I-Kd and 127I-Kd were similar. The relatively low 127I concentrations and low values of both 127I-Kd and 125I-Kd indicate that some of the I deposited on the soil surface have been transported to depths greater than 10 cm. On the other hand, high 127I-Kd/125I-Kd ratios in the uppermost 10 cm of soil indicate that some of the 127I bound to that soil could not be exchanged with exogenous 125I. Although a previous study has shown a power function relationship between 125I-Kd and C-Kd, our data show that the relationships of both 125I-Kd and 127I-Kd to C-Kd are exponential functions. The reason for these conflicting results is unknown. Nonetheless, our data clearly show Kd values for both 125I- and 127I to be dependent on C-Kd. In addition, the dependence of both 127I-Kd and 125I-Kd on C-Kd suggests that organic material in the soil has a role in the transport of I down the soil profile.

SPECIATION OF IODINE IN SOIL SOLUTION IN FOREST AND GRASSLAND SOILS IN ROKKASHO, JAPAN.

The behaviour of I in soil depends on its chemical form in soil solution. Stable I (127I) in the soil solution under actual soil conditions was investigated as a natural analogue of long-lived radioiodine (129I). Soil samples were collected at 5-cm depth intervals down to 20 cm from forests and grasslands in Rokkasho, where the Japanese first commercial nuclear fuel reprocessing plant is located, and the soil solution was extracted by centrifugation. Almost half of total I in the soil solution was iodide, and the other half was dissolved organic I (DOI), with iodate under the detection limit. The proportion of DOI in total I at 0-5 cm depth was larger than the proportions at 5-20 cm depth. The concentration of DOI was positively correlated with that of DOC in the soil solution, suggesting that the behaviour of DOI in the surface soil is affected by labile organic matter dynamics.

Interferon-beta augments eosinophil adhesion-inducing activity of endothelial cells.

Viral infections induce exacerbations of asthma. One of the earliest host responses to viral infections is the production of innate cytokines including type I interferons (IFNs), such as IFN-beta, which may act to modify airway inflammation. The objective of the present study was to investigate whether IFN-beta modifies the eosinophil adhesion-inducing activity of endothelial cells. Human umbilical vein endothelial cells (HUVECs) were stimulated with IFN-beta for 24 h in the presence or absence of tumour necrosis factor (TNF)-alpha. Eosinophils were isolated from the peripheral blood of healthy volunteers. The ability of the IFN-beta-stimulated HUVEC monolayers to induce eosinophil adhesion was assessed according to the eosinophil peroxidase assay. Eosinophil adhesion to HUVECs was significantly augmented by IFN-beta in the presence of TNF-alpha but not in its absence. The augmented adhesion was inhibited by anti-alpha(4) integrin monoclonal antibody (mAb) or anti-beta(2) integrin mAb. IFN-beta significantly enhanced the expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 on HUVECs in the presence of TNF-alpha. Interferon-beta can augment the adhesiveness of endothelial cells to eosinophils, mainly through the expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1. This action of interferon-beta may contribute to the intensification of airway inflammation in asthma that is associated with exacerbations induced by viral infections.

Changes in the chemical form of exogenous iodine in forest soils and their extracts.

Information about the chemical form of exogenous iodine in soil is important for predicting the mobility and behaviour of radioiodine in the terrestrial environment. In this study, soil samples collected at various depths in a pine forest in Rokkasho, Japan, were spiked with stable iodine (as iodide or iodate); after incubation of the spiked soils for 1 or 14 d, the chemical forms of iodine were investigated in both the soils and their water extracts. In surface soil and its extracts, inorganic iodine was found to have been transformed to organically bound forms after incubation for 14 d, resulting in a decrease in the amount of water-extractable iodine in the soil. In contrast, in subsurface soil, which had low organic matter content, the predominant chemical form of iodine after incubation did not differ from that in the spiked soil, and the amount of water-extractable iodine did not decrease noticeably.

Ornithine ketoacid aminotransferase in the bovine eye.

Ornithine ketoacid aminotransferase in bovine ocular tissues was studied biochemically. The retinal pigment epithelium, ciliary body, iris, and neuroretina showed high specific activity. The cornea and choroid revealed a lower activity. Aqueous humor, lens, vitreous body, and sclera showed no activity. The pH optima of the enzyme in the retinal pigment epithelium and ciliary body were near 8.0.

Dual delivery system for argon laser photocoagulation. Improved techniques of the binocular indirect argon laser photocoagulator.

A dual delivery system provided alternate delivery of the laser beam to the slit lamp and binocular ophthalmoscope. Ophthalmologists may choose between the two systems in accordance with the nature and location of the fundus lesion. A pilot study comparing the rate of laser hit between the slit-lamp photocoagulator and the binocular indirect argon laser photocoagulator (BIALP) showed that accuracy was better with the slit lamp and BIALP when they were operated in the sitting position than with the BIALP operated in the standing position. A photo-electric safety switch was attached to the blocking filter of the BIALP to protect operator's and patient's eyes. The improved machine and techniques increased the efficiency and safety of argon laser photocoagulation. Postoperative use of the BIALP was of particular value. Laser photocoagulation in children's eyes became possible for the first time with the BIALP.

Ultrastructural observations of adherent cell pairs in hydra vulgaris

Previous morphological studies of cell sorting in Hydra vulgaris have considered only clusters of cells. Here, we present ultrastructural observations on the adherent region of cell pairs brought into contact (following dissociation) using a three-dimensional laser manipulator. There was a much larger area of close membrane contact between endodermal cell pairs in comparison with ectodermal cell pairs. Separation distances between membranes were categorized into three classes: closest distance (<4 nm); medium distance (5-25 nm); and cleavage (>25 nm). The sum of distances in the closest and medium categories as a proportion of total contact length was significantly greater (P<0.01) for endodermal cells (49.0+/-6.5 %) than for ectodermal cells (26.7+/-4. 4 %). In intact Hydra, this sum of distances was also significantly greater for endodermal cells, indicating that newly adherent cells, even after adhesion for only 10 min, display similar morphological characteristics to cells in intact Hydra. This suggests that close membrane contacts contribute to differential cell adhesion, which may form the basis of the cell sorting process.

Survey of complications of indocyanine green angiography in Japan.

PURPOSE: We evaluated the safety of indocyanine green for use in fundus angiography. METHODS: We sent a questionnaire concerning complications of indocyanine green to 32 institutions in Japan, which were selected on the basis of the client list from the Topcon Company, which manufactures the indocyanine green fundus camera. RESULTS: Ophthalmologists at 15 institutions responded, reporting a total of 3,774 indocyanine green angiograms performed on 2,820 patients between June 1984 and September 1992. Before angiography, intradermal or intravenous indocyanine green testing, or both was performed at 13 of 15 institutions. For three patients, the decision was made not to proceed with angiography after positive preangiographic testing. The dosage of indocyanine green used for angiography varied from 25 to 75 mg, depending upon the institution. There were 13 cases of adverse reactions (0.34%), ten of which were mild reactions such as nausea, exanthema, urtication, itchiness, and urgency to defecate, and did not require treatment. Also recorded were one case of pain of the vein, which required treatment, and two cases of hypotension. The two hypotensive patients required treatment for shock. CONCLUSIONS: A comparison of frequency of adverse reactions to indocyanine green with the previously reported frequency of such reactions to fluorescein sodium indicated that indocyanine green is a safe as fluorescein for use in angiography.

Gyrate atrophy with hyperornithinaemia: different types of responsiveness to vitamin B6.

Three cases of Japanese patients with gyrate atrophy of the choroid and retina with hyperornithinaemia were studied clinically and biochemically. The types of disease differed in responsiveness to vitamin B6. In-vivo responsiveness to vitamin B6 was correlated with in-vitro data. It is suggested that the in-vitro examination of the influence of pyridoxal phosphate on ornithine ketoacid transaminase activity in cultured fibroblasts may be useful in ascertaining the efficacy of vitamin B6 treatment in gyrate atrophy. In addition the early development of the fundus lesions was observed in one case (case 1), and the ciliary body abnormality and chorioretinal atrophy were noted in another (case 3).

Effects of aging on fluorescein leakage in the iris and angle in normal subjects.

PURPOSE: To determine the presence of fluorescein leakage from the iris and angle in normal subjects, and how it is affected by aging. METHODS: The subjects were 92 normal volunteers and patients with senile cataract who ranged in age from 20 to 93 years and were free from any systemic or ocular diseases. Fluorescein iris and angle photography and color iris and angle photography were performed using a goniolens and a photo slit lamp. RESULTS: Radial ciliary body vessels were found in 22 eyes (24%), radial iris vessels or trabecular vessels in 7 eyes (8%), and circular ciliary band vessels were seen in 4 eyes (4%). Goniovessels were found in 8 of 30 eyes (27%) of those under 50 years of age. No significant difference in the incidence of goniovessels was found between those over and under age 50 (P < .01). In the pupillary margin, fluorescein leakage was seen in 1 of 30 eyes (3%) in the age group under 50 years, whereas leakage was found in 30 of 62 eyes (48%) in the age group over 50 years. In the anterior chamber angle, leakage was seen in 4 of 30 eyes (13%) under age 50 years, and in 38 of 62 eyes (61%) over age 50 years (P < .05). CONCLUSIONS: These findings suggested that the incidence of leakage of fluorescein from the pupillary margin and anterior chamber angle tends to increase with age. Thus, when leakage of fluorescein in angle and iris is observed, it is important to consider the physiological changes resulting from aging.

Daily intakes of 232Th and 238U in Japanese males.

Diet samples were collected by a duplicate portion method from 31 locations in Japan and were analyzed by inductively coupled plasma mass spectrometry. Average daily intakes per adult male were estimated at 1.7 mBq for 232Th and 8.8 mBq for 238U.

[Effects of aging on fluorescein iris and angle photography in normal subjects].

In the present study we took the fluorescein iris and angle photography of normal eyes and studied them according to different age groups. The range of age in 108 eyes of 92 subjects was from 20 to 93 years. They were free from any systemic diseases or ophthalmic diseases which would cause iris rubeosis. Fluorography was carried out using a Mizuno Trabeculens to determine the leakage points of fluorescence from the iris and the angle. In the angle there were gonio vessels which revealed no leakage of fluorescein. They were observed in 8 of 30 eyes (27%) for subjects in the fifth decade of life or less and in 24 of 78 eyes (31%) for subjects aged 50-90. No significant difference was seen between the two age groups. As to variations of gonio vessels, radial ciliary body vessel was found in 23 eyes, radial iris vessel or trabecular vessel in 10 eyes, and circular ciliary band vessel in 7 eyes. In the pupillary margin no leakage was seen in 30 eyes of 30 cases in the fifth decade of life or less, while leakage was found in 33 of 78 eyes, 42 of 62 cases over the fifth decade of life. In the angle leakage was seen in 4 of 30 eyes, 13 of 30 cases in the fifth decade of life or less, while leakage was observed in 43 of 78 eyes over the fifth decade of life. These results suggested that leakage of fluorescence from the pupillary margin, the angle or both increases with age.(ABSTRACT TRUNCATED AT 250 WORDS)

Measurement of atmospheric radon daughter concentrations at the campus of Fukushima Medical College.

Radon daughter concentrations in outdoor and indoor air were measured at the campus of Fukushima Medical College. Radon daughters in the air were sampled with a flow rate of 20 L/min through a glass fiber filter or a membrane filter, and the decay of activity on the filter was analyzed with two types of technique, i.e., the gross-beta one-count method using a G.M. tube and the alpha spectroscopic method using a semiconductor detector. The present paper describes principles and techniques of the measurement in detail.

Radiation dosimetry with an electron spin resonance spectrometer.

Radiation dosimetry was undertaken using an electron spin resonance (ESR) spectrometer in students' laboratory work. Sugar was used as a dosimeter element and irradiated with both an X-ray generator (34 kVp, 8 mA) and a 60Co sealed source (3.7 MBq). The ESR system detects unpaired electrons created by the ionizing radiation. The lowest detection limit of the absorption dose was 20 Gy.

Strength distribution in the tibia.

Stress fracture of a tibia is rarely associated with osteoarthros of the knee joint (gonarthrosis), whereas the present authors experienced a case of tibial stress fracture with high level lateral flail. To make an analysis with the statics of an elastic body, the shape of the tibia was read from a roentgenogram with a digitizer. The bend of a tibia was expressed with curvature (the reciprocal with curvature radius); fracture was expected to occur where the curvature was large. From the analysis, the fracture had occurred near one of the maximums of the curvature when the knee side was fixed and a force was applied to the ankle side --walking situation, e.g. The analysis also has indicated that the tibia would be very weak when the ankle side was fixed--skiing situation, e.g.

Storage and analysis of Goldmann's visual fields with a personal computer.

A method of storing and analyzing Goldmann's visual fields with a personal computer has been developed and applied to cases of retinal detachment. Original two-dimensional analogue data, obtained manually by ophthalmologists, were digitized and transferred to a personal computer. A one-megabyte floppy disk was able to store data of 170 charts. Stored data were easily displayed on the CRT of the computer using two- and three-dimensional graphics. Total and four quadrant areas surrounded by isopter curves were calculated for fellow eyes, diseased eyes and operated eyes. Furthermore, weighted areas with four types of weighting function which attach more importance to the center than the periphery of a visual field were calculated. Power type weighting function was found to give the most significant effect on emphasizing abnormality of eyes with retinal detachment.