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The characteristics and performance of the prototype of a Position-Sensitive Tissue-Equivalent Proportional Chamber (PS-TEPC), consisting of a miniaturized micro-pixel chamber (μ-PIC), were investigated. The gas–gain curve of the μ-PIC and an approximate function with which to convert measured collected charge into the primary charge ionized by incident heavy-ion particles were obtained. The measured Linear Energy Transfer (LET) indicated good agreement with that of the injected beam calculated using SRIM2008 code in the LET range from 0.4 to 180keV/μm, which roughly covers the whole LET range required for space dosimeters. As expected, the measured energy resolution improved with increasing LET of the injected beam. It was estimated to be 27% for 0.4keV/μm, which is just about the LET of minimum-ionizing particles. Consequently, it was confirmed that the PS-TEPC exhibits no significant undesirable feature but is well suited for space dosimetry.

Background Attention-deficit hyperactivity disorder (ADHD) is the most commonly diagnosed behavioural disorder of childhood, affecting 3–5% of school-age children. The present study investigated whether the supplementation of soy-derived phosphatidylserine (PS), a naturally occurring phospholipid, improves ADHD symptoms in children. Methods Thirty six children, aged 4–14 years, who had not previously received any drug treatment related to ADHD, received placebo (n = 17) or 200 mg day–1 PS (n = 19) for 2 months in a randomised, double-blind manner. Main outcome measures included: (i) ADHD symptoms based on DSM-IV-TR; (ii) short-term auditory memory and working memory using the Digit Span Test of the Wechsler Intelligence Scale for Children; and (iii) mental performance to visual stimuli (GO/NO GO task). Results PS supplementation resulted in significant improvements in: (i) ADHD (P

Large sized bubble detectors with different sensitivities have been irradiated with high-energy protons at the cyclotron in RIKEN, Japan. Distributions of bubbles induced by the protons in the detectors have been studied. It shows that quite a large number of random bubbles are produced in the detectors in the range traveled by the beam protons. The existence of random bubbles hints that high-energy protons as an important component of primary and secondary cosmic rays at higher altitude and in space may cause significant number of bubbles in the bubble detectors in aircrafts or spacecrafts. The origin of the random bubbles has been investigated. The detection efficiencies of bubble detectors for protons via the random bubbles have been determined, being (0.93 ± 0.27) × 10 −2 , (4.6 ± 1.5) × 10 −2 and (4.7 ± 1.7) × 10 −2 (Bubble cm −3 )/(Proton cm −2 ), respectively for T-14, T-24 and T-12 types of bubble detectors. The detection efficiencies for protons are quite high, which are about two orders of magnitude higher than that for 0.3–19 MeV mono-energetic neutrons. The astonishing high efficiencies for protons can only be attributed to Rutherford scattering of protons with nuclei of C, F, and Cl in the compositions of superheated liquid droplets in the detectors. The recoil nuclei of C, F and Cl from Rutherford scattering create the random bubbles. In contrast, in terrestrial calibrations of bubble detectors with mono-energetic neutrons, only nuclear interactions of neutrons with nuclei are involved. Special consideration must be given to the effect of Rutherford scattering of high-energy protons on detection of neutrons with bubble detectors at higher altitude and in space.

We have developed a new type of photon detector for an experiment aimed at searching for the lepton flavor violating decay μ+ → e+γ. In this experiment, a total of 900 L of liquid xenon is used in order for the scintillation detector to detect γ-rays with an extremely high sensitivity, where the liquid xenon is viewed by an array of 846 photomultipliers from all sides. The entire amount of xenon should be stored in certain storage systems before the start of the experiment, during detector maintenance in the period of accelerator shutdown, etc. We have developed a new liquid xenon storage system by employing the zero boil-off condition by using a pulse tube cryocooler. The details of system and its performance results are described in this article.

The maximum scintillation yields in NaI(Tl) and CsI(Tl) crystals were estimated theoretically by applying the scintillation model for liquid rare gases to crystal scintillators. Average energies required to produce one scintillation photon in the maximum scintillation yield, W so , were estimated to be 10.6 ± 0.3 or 11.6 ± 0.3 eV for NaI(Tl) and 11.6 ± 0.3 or 12.5 ± 0.3 eV for CsI(Tl). The new experiment on scintillation yields gives W so of 10.8 ± 2.0 eV for NaI(Tl) and 11.3 ± 2.1 or 9.3 ± 1.7 eV for CsI(Tl). The values show good agreement with the theoretical estimations. These results demonstrate that the scintillation model in liquid rare gases is applicable to inorganic scintillators such as NaI(Tl) and CsI(Tl) crystals.

This is a case report of chylous ascites caused by performing para-aortic lymph node dissection for a patient with cervical cancer. Postoperative chylous ascites is a rare condition that usually develops as a result of operative trauma to the thoracic duct, cisterna chyli, or their major tributaries. It has mainly occurred in thoracic operations, and chylous ascites has rarely been reported in gynecologic surgery. It is associated with serious nutritional and immunologic consequences due to the constant loss of protein and lymphocytes. Treatment that comprises conservative and surgical procedures is selected based on disease severity. We experienced massive chylous ascites after para-aortic surgery and successfully managed it conservatively with dietary intervention and parenteral nutrition.

Calculations on the formation of a linear track of a heavy ion in bubble detector have been carried out based on a theoretical model considering the minimum energy (including bubble surface energy, internal energy, evaporation energy, expansion energy, kinetic energy and viscous energy) required during the formation of a critical bubble at the cost of the ionization energy of the heavy ion. The calculated minimum energy is 8.99 keV for dichlorodifluoromethane (R-12) at 25 °C. The results of calculations have been combined with those of calibrations of bubble detectors with heavy ions at accelerator. The threshold (1.51 ± 0.04) MeV mg - 1 cm 2 is obtained in the calibration with heavy ions for the above liquid and temperature. It shows that the distance over which the heavy ion traverses and transfers energy to the superheated liquid to produce a critical bubble is 4.67 times the radius of the seed bubble. The radius of the cylinder along which the heavy ion deposits energy to form a seed bubble is about 5.2 nm. This dimension indicates that the process of track formation in bubble detectors is consistent with the model of thermal spike.

We are developing a new type of photon detector for an experiment to search for muons decaying into a positron and a gamma ray. In this experiment, the photon detector will utilize liquid xenon (Xe) as the scintillation material. Good transparency of the liquid Xe is required in order to gain the highest performance out of the detector. Impurities like water and oxygen must be removed efficiently for this purpose. We have developed a new purification system, dedicated to removing water from liquid Xe, by employing a cryogenic centrifugal pump and molecular sieves. The performance of the system is described in this article.

Experiments have been performed to measure the response of the silicon-based linear energy transfer (LET) spectrometer (RRMD-III) to protons with energies ranging from 1 to 70 MeV. The beam energies incident upon RRMD-III were obtained using plastic polycarbonate degraders with mono-energetic proton beams that were extracted at 70, 40 and 25 MeV from a cyclotron. The energy loss in the degraders never exceeded 70% of the incident energy in order that the energy spread of the emerging protons created by straggling and scattering effects could be suppressed. Estimates of the LET were influenced by the asymmetric energy distribution of the degraded beam. Protons with energies less than 12.2 MeV did not reach the second Si detector in RRMD-III and were not measured. Measured values of LET were within ±7% of the expected value for incident protons that had an energy sufficient to penetrate the second Si detector in RRMD-III (E>15.4 MeV). The LET of stopping particles was computed using a lookup table listing LET vs E, and a simple stopping power formula for a particle with charge Z and energy E R, where E R is the energy of the stopping particle measured in the second Si detector.

Borak, T. B., Doke, T., Fuse, T., Guetersloh, S., Heilbronn, L., Hara, K., Moyers, M., Suzuki, S., Taddei, P., Terasawa, K. and Zeitlin, C. J. Comparisons of LET Distributions for Protons with Energies between 50 and 200 MeV Determined Using a Spherical Tissue-Equivalent Proportional Counter (TEPC) and a Position-Sensitive Silicon Spectrometer (RRMD-III). Radiat. Res. 162, 687–692 (2004). Experiments have been performed to measure the response of a spherical tissue-equivalent proportional counter (TEPC) and a silicon-based LET spectrometer (RRMD-III) to protons with energies ranging from 50–200 MeV. This represents a large portion of the energy distribution for trapped protons encountered by astronauts in low-Earth orbit. The beam energies were obtained using plastic polycarbonate degraders with a monoenergetic beam that was extracted from a proton synchrotron. The LET spectrometer provided excellent agreement with the expected LET distribution emerging from the energy degraders. The TEPC cannot ...

We are developing a new type of photon detector in preparation of an experiment to search for muons decaying into positrons and gamma rays. In the experiment, the photon detector will utilize liquid xenon (Xe) as the scintillation material because of its fast response, large light yield, and high density. The scintillation light emitted in liquid Xe will be observed directly by positioning photomultipliers (PMTs) in the liquid without using a transmission window. In order to determine proper experimental procedures and to study the detector response to gamma rays, we constructed a prototype utilizing a 100 l volume of liquid Xe. The current status and future prospects of detector development are reported in this article.

Five types of bubble detectors (T-15, T-34, T-12, T-24 and T-14) of large volume and different sensitivities were developed in the China Institute of Atomic Energy for the purpose of heavy ion research. Calibrations were carried out with beams of high-energy protons, He, C, Si, Ar, Fe, Kr and Xe, at accelerators in the energy region 150– 650 MeV /u . The bubble detectors were demonstrated to be a family of detectors for recording tracks of high-energy heavy ions with atomic numbers from Z=1 (proton) to all the numbers in the whole periodic table of elements. The threshold levels of the detectors differ from each other with values 0.05±0.01 (T-15), 1.62±0.05 (T-34), 1.68±0.03 (T-12), 2.24±0.06 (T-24) and 6.04±0.80 ( T- 14) MeV mg −1 cm 2 , respectively, which are about the same or even lower than the levels of plastic track detectors for recording heavy ions. The distinguishing features of bubble detectors are high sensitivity, active recording, real-time display, volume registration and background discriminating capacities. Bubble detectors are a new type of high sensitivity detectors and are very promising for detection of heavy ions, neutrons and exotic particles.

A novel gamma-ray detector based on a liquid xenon scintillator is under development for a new experiment to search for the lepton flavor violating process μ + →e + γ at the Paul Scherrer Institute (PSI). The experiment is designed to have a sensitivity down to 10 −14 branching ratio. We constructed a prototype detector with an active volume of 69 l to demonstrate the performance of the proposed detector for high-energy gamma rays of around 50 MeV. After a test of the cryogenic system for the prototype detector, we have begun studies with the prototype using a gamma-beam up to 40 MeV from the laser Compton backscattering facility at the TERAS electron storage ring of the National Institute of Advanced Industrial Science and Technology (AIST).

We are developing a new type of photon detector for an experiment to search for muons decaying into positrons and gamma rays. The detector utilizes liquid xenon as a scintillation material. The scintillation light emitted in liquid xenon is directly observed by photomultipliers (PMTs) located in the liquid without the use of a transmission window. In order to study the detector response, we have constructed a prototype with an active volume of about 70 l surrounded by 228 PMTs. For studying the detector response we conducted electron and gamma beam tests together with detector calibration using alpha sources and cosmic-ray events. In this article we describe preliminary results obtained in these tests.

Bubble detectors were irradiated with protons and demonstrated that a special type of bubble detector could directly record proton tracks. The track of a proton is composed of one or more bubbles at the Bragg peak in the end of the proton range. A proton can produce at least one bubble as its track. Successful recording of proton tracks shows that bubble detectors can be used as a new type of heavy ion track detector to register all nuclei with atomic numbers in the entire Periodic Table of Elements. The applications of bubble detectors based on proton registration have been desired in the study of nuclear interactions, space research and cancer therapy.

We are developing a new type of photon detector for an experiment to search for muons decaying into a positron and gamma ray. Our sensitivity on the branching ratio is expected to reach 10/sup -14/ by use of the world's most intense continuous muon beam at Paul Scherrer Institut (PSI). In this experiment, the photon detector will utilize liquid Xe as a scintillation material because of its fast response, large light yield, and high density. The scintillation light emitted in liquid Xe will be directly observed by photomultipliers (PMTs) located in the liquid without the use of a transmission window. In order to study the detector response to gamma rays, we have constructed a prototype with an active volume of 2.3 /spl times/ 10/sup 3/ cm/sup 3/ surrounded by 32 PMTS. The PMT is a new development enabling operation at temperatures as low as liquid Xe (165 K). Energy, position, and timing resolutions have been evaluated using gamma-ray sources ranging from 320 keV to 1835 keV. The performance of the prototype is presented.

A small scintillating fiber camera for space dosimetry was developed. The camera consists of a scintillating fiber stack bundled with 0.25-mm square fibers, two image intensifier units whose input windows are 40 mm in diameter, and two photomultipliers. Neutron events are distinguished from gamma-ray events by observing three-dimensional track images of recoil protons and electrons. Experimental results show that events caused by recoil protons with energies above 5 MeV can be distinguished from gamma-ray events. The purpose of this camera is to evaluate the LET, of charged particles produced in the interaction of neutrons with the nucleus in scintillating fibers. The camera is expected to measure the dose contribution from higher energy neutron, especially, more than /spl sim/10 MeV, which is the upper limit energy of the present measurement in space.

OBJECTIVE—The genes for killer cell inhibitory receptors (KIRs) have been cloned and their functions and responses to other molecules, including cytokines, have been partially clarified. However, the expression of KIRs has not been analysed in patients with autoimmune diseases, such as rheumatoid arthritis (RA), who are highly susceptible to microbial infection. Therefore, KIR expression on lymphocytes in patients with RA, and the regulation of KIR expression by interleukin 2 (IL2) in RA was investigated. METHODS—CD158a/b expression on peripheral blood mononuclear cells (PBMC) obtained from 25 patients with RA and 14 healthy subjects was analysed by flow cytometry. Additionally, PBMC from the two groups of subjects were cultured in RPMI 1640 medium with or without IL2 for 48 hours, and then their CD158a/b expression was analysed. RESULTS—The rate of CD158a expression on the CD8+ cells was lower in patients with RA than in healthy subjects, though there was no significant difference in the CD158a/b expression on the CD16+ cells between the two groups. The upregulation of CD16+CD158a/b+ cells in response to IL2 was significantly reduced in patients with RA compared with healthy subjects. CONCLUSION—The reduced induction of KIR expression in response to IL2 may provide insight into the reason for the high susceptibility of patients with RA to microbial infection.

A scintillating fiber camera for three-dimensional imaging was newly developed for radiation dosimetry in spacecraft. The camera consists of a scintillating fiber stack, an image intensifier unit and photomultipliers for triggering events. The scintillating fiber stack has 100 scintillating fiber layers. The layers are alternatively stacked up to be perpendicular to each other. The stack is coupled to a two-stage image intensifier and then coupled to a CCD camera for the track readout. Each fiber layer consists of 100 scintillating fibers and the fiber stack composed of 100 layers leads us to a sensitive volume of 50×50×50 mm 3 . Each fiber has a cross-section of 0.5×0.5 mm 2 . It is found that the camera has the capability to clearly identify charged particles, neutrons and γ-rays by observing individual three-dimensional images of those tracks. The threshold energy for identification of neutrons and γ-rays is 5– 10 MeV for recoil proton energy when the coincidence signals from 2 photomultipliers are used as triggers and is expected to be 2–3 MeV when the triggers from either photomultiplier are used. The whole energy region for neutron dosimetry will be covered by the combination with the Bonner spheres for the energy region lower than ∼10 MeV .

We constructed a liquid xenon calorimeter with electrodes of multi-parallel plates. This calorimeter is regarded as homogeneous because of thin electrodes and is expected to have an excellent energy resolution of 0.34% for 70 GeV electrons by EGS4 simulation. We tested it for 10–70 GeV electrons at CERN. The measurements were made without signals from a readout channel at about 4 radiation length lost by failure. By simply summing other signals the energy resolution of 2% (r.m.s.), which includes the beam momentum spread of 0.65%, was obtained for 70 GeV electrons. The signal from the lost channel can be estimated by fitting a build-up curve to the obtained signals for each event. If the correction for the contribution from the lost channel is made by the fitting method, the energy resolution is 0.9%, which is close to the resolution of 0.71% obtained by the simulation.

A new type of real-time radiation monitoring device, RRMD-III, consisting of three double-sided silicon strip detectors (DSSDs), has been developed and tested on-board the Space Shuttle mission STS-84. The test succeeded in measuring the linear energy transfer (LET) distribution over the range of 0.2 keV/micrometer to 600 keV/micrometer for 178 h. The Shuttle cruised at an altitude of 300 to 400 km and an inclination angle of 51.6 degrees for 221.3 h, which is equivalent to the International Space Station orbit. The LET distribution obtained for particles was investigated by separating it into galactic cosmic ray (GCR) particles and trapped particles in the South Atlantic Anomaly (SAA) region. The result shows that the contribution in dose-equivalent due to GCR particles is almost equal to that from trapped particles. The total absorbed dose rate during the mission was 0.611 mGy/day; the effective quality factor, 1.64; and the dose equivalent rate, 0.998 mSv/day. The average absorbed dose rates are 0.158 mGy/min for GCR particles and 3.67 mGy/min for trapped particles. The effective quality factors are 2.48 for GCR particles and 1.19 for trapped particles. The absorbed doses obtained by the RRMD-III and a conventional method using TLD (Mg(2)SiO(4)), which was placed around the RRMD-III were compared. It was found that the TLDs showed a lower efficiency, just 58% of absorbed dose registered by the RRMD-III.

An allene-doped liquid argon ionization chamber with 48 mm×48 mm×40 mm sensitive volume has been constructed for precise energy measurement of heavy ions at around 100 MeV/n. An energy resolution of 0.6%–0.7% (FWHM) was achieved for Ca and Ar ions both at 78 MeV/n.

Although there have been many reports regarding the structure of the parathyroid glands of various terrestrial mammals, little is known about the parathyroid glands of marine mammals including Cetacea. The morphology of the parathyroid glands of three Risso's dolphins, Grampus griseus (about 3 m in length and 300 kg in weight), and three bottlenose dolphins, Tursiops truncatus (about 3 m in length and 300 kg in weight), was examined macroscopically and microscopically. The dolphins examined in the present study had two or four parathyroid glands that varied in size and location on the thyroid gland. Each parathyroid gland was encapsulated by fibrous tissue on the dorsal surface of the thyroid gland, and was divided into several lobules by interlobular connective tissue which contained numerous capillaries. The parenchymal cells consisted of pale staining chief cells. Each cell was polygonal and about 15 microm in diameter, and had one round or oval nucleus. Oxyphil cells were not found. Considering their greater body size, the parathyroid glands were rather small. By electron microscopic observation, the parathyroid gland of the bottlenose dolphin had sparse granular endoplasmic reticulum, poorly developed Golgi complexes, and abundant secretory granules in the cytoplasm of the chief cells. These results support a possibility that the activity of the parathyroid gland is suppressed to adapt to a sea habitat.

We measured the collected charges, the energy resolution and their time stability using an ionization chamber filled with liquid xenon doped with trimethylamine (TMA) as photoionization molecules. When liquid xenon was doped with a low concentration of TMA purified at −110°C, the chamber was operated stably at −110°C for about 50 h.

To clarify if the enhancement of rotational behavior induced by repeated administration of SKF38393 is mediated by upregulation of D1 and/or D2 receptors in the striatum, we investigated effects of SCH23390 and sulpiride on SKF38393-induced rotational behavior and the changes in striatal dopamine receptors in rats with unilateral nigrostriatal 6-hydroxydopamine lesions (1). Repeated weekly administration of SKF38393 markedly enhanced the number of rotations and shortened the latency of rotational behavior depending on the number of SKF38393 administrations 1 or 6 weeks after the treatment with 6-OHDA (2). A selective D1 antagonist, SCH23390, but not a selective D2 antagonist, sulpiride, suppressed SKF38393-induced rotation and inhibited the enhancement by the repeated administration (3). Repeated administration of SKF38393 did not modify the density and the affinity of either the striatal D1 or D2 receptors in the striatum. These results suggest that the enhancement of SKF38393-induced rotational behavior by the repeated administration is not associated with the upregulation of striatal D1 and D2 receptors.

The ultrastructure of the parathyroid glands of phosphate-treated golden hamsters exposed to a 5-G environment was studied. In the phosphate-treated animals exposed to a hypergravity environment, the Golgi complexes associated with numerous prosecretory granules, and the enlarged intercellular spaces containing floccular or finely particulate material showed a significant increase compared to those of the control, centrifuged, and phosphate-treated groups, and the cisternae of the granular endoplasmic reticulum showed a significant increase compared to those of the control and phosphate-treated groups. In addition, numerous secretory granules were situated close to the plasma membrane of chief cells in the phosphate-treated animals exposed to a hypergravity environment. These findings suggest that the synthesis, and to a greater extent the release of secretory granules may be markedly stimulated, in the parathyroid glands of phosphate-treated animals exposed to a hypergravity environment.

The effects of different ages on large vacuolar bodies in the parathyroid glands of golden hamsters after short-term treatment with calcium were investigated. In the parathyroid glands of the young and adult animals 15 min and the senile animals 15 and 60 min after administration of calcium, the percent area occupied by large vacuolar bodies was significantly increased as compared to that of the young, adult and senile control animals, respectively. These findings suggest that the percent area occupied by large vacuolar bodies is increased in response to acute hypercalcemia. It is thought that in the parathyroid glands suppressed by hypercalcemia there is a relationship between the percent area occupied by large vacuolar bodies and aging.

Radiation effects on human body are evaluated using dose equivalent H, defined as the product of the absorbed dose and the quality factor given as a function of LET. In space, there exist many kinds of radiations, such as galactic cosmic rays and geomagnetic trapped particles, where charged particles and neutrons are the main components contributing to radiation dose in space. Since LET of these radiations widely distributes, it is essential to measure directly LET for evaluation of H in space. The Tissue Equivalent Proportional Counter (TEPC) has been used as a standard space dosimeter, which is a simple gas counter made of tissue equivalent materials. In TEPC, since no position information is given, a lineal energy is measured instead of LET. Obviously the lineal energy does not represent LET accurately. The dose obtained using TEPC is reported to be inconsistent with those measured with real LET spectrometers. We started to develop a new dosimeter named as Position Sensitive Tissue Equivalent Chamber (PS-TEPC), which is based on a time projection chamber using Micro Pixel Chamber (mu-PIC) as two- dimensional position-sensitive detector. In this study, we aim to demonstrate feasibility of PS-TEPC and to complete a prototype of PS-TEPC usable in space. The performance was tested by using the heavy ion beams to examine its abilities of 3D-tracking and energy measurement.

The optical properties of LXe in the vacuum ultra violet (VUV), determining the performance of a scintillation calorimeter, are discussed in detail. The available data, measured in a wider spectral region from visible to UV light, and in a large range of Xe densities, from gas to liquid, are examined. It is shown that this information can be used for deriving the LXe optical properties in the VUV. A comparison is made with the few direct measurements in LXe for VUV light resulting from the LXe excitation by ionizing particles. A useful relation is obtained which connects the Rayleigh scattering length to the refractive index in LXe., 20 pages, 12 figures

We are developing a liquid xenon calorimeter for the MEG experiment. This experiment, to be performed at the Paul Scherrer Institut (PSI) in Villigen (CH), was designed by an Italian-Japanese-Russian-Swiss collaboration to search for the /spl mu//sup +//spl rarr/e/sup +//spl gamma/ decay, forbidden in the standard model of electroweak and strong interactions. The photon four momentum is to be measured by an innovative C-shaped 800 litres liquid xenon calorimeter read by more than 800 photo-multiplier tubes. An absorption length for Xe scintillation light larger than 100 cm has been measured. The performance of such a detector has been measured using a large volume prototype (100 litres) in a test beam at PSI, using high energy photons from decays of neutral pions from a charge exchange reaction of negative pions on protons. A resolution of 5% FWHM was obtained.

An 800L liquid xenon scintillation $\gamma$ ray detector is being developed for the MEG experiment which will search for $\mu^+\to\mathrm{e}^+\gamma$ decay at the Paul Scherrer Institut. Absorption of scintillation light of xenon by impurities might possibly limit the performance of such a detector. We used a 100L prototype with an active volume of 372x372x496 mm$^3$ to study the scintillation light absorption. We have developed a method to evaluate the light absorption, separately from elastic scattering of light, by measuring cosmic rays and $\alpha$ sources. By using a suitable purification technique, an absorption length longer than 100 cm has been achieved. The effects of the light absorption on the energy resolution are estimated by Monte Carlo simulation., Comment: 18 pages, 10 figures (eps). Submitted to Nucl. Instr. and Meth. A

To investigate whether docosahexaenoic acid (DHA) supplementation was able to ameliorate attention-deficit/hyperactivity disorder(AD/HD) symptoms in AD/HD children.A placebo-controlled double-blind study with 40 AD/HD (including eight AD/HD-suspected) children of 6-12 y of age who were mostly without medication. Subjects of a DHA group (n=20) took active foods containing fish oil (fermented soybean milk, bread rolls and steamed bread; 3.6 g DHA/week from these foods) for 2 months, whereas those of a control group (n=20) took indistinguishable control foods without fish oil. The following items were measured at the start and end of the study: (1) attention deficit, hyperactivity and impulsivity (AD/HD-related symptoms according to DSM-IV criteria); (2) aggression assessed by both parents and teachers; (3) visual perception (finding symbols out of a table); (4) visual and auditory short-term memory; (5) development of visual-motor integration; (6) continuous performance; (7) impatience.Changes in tests 1, 2, 3, 5 and 7 over time did not significantly differ between the two groups. However, visual short-term memory and errors of commission (continuous performance) significantly improved in the control group compared with the changes over time in the DHA group (P=0.02 and 0.001, respectively). Recalculation without AD/HD-suspected subjects (n=4 each group) showed similar P-values with regard to both measures.DHA supplementation did not improve AD/HD-related symptoms. Treatment of ADHD with fatty acids deserves further investigation, but careful attention should be paid as to which fatty acid(s) is used.

The LET distributions in front of the 80 cm-thick concrete side shield at the CERF facility were measured with a Si detector telescope (RRMD-III) covered with and without a 1 cm-thick acrylic plate. In these measurements, a slight difference between the LET distributions was seen as a result of recoil protons and/or carbon particles by neutrons. Also, the LET distributions are compared with the micro-dosimetric spectrum (i.e., lineal energy distribution) measured with a cylindrical TEPC under the same conditions.

Crude preparations of Fun-boi (Stephania tetrandra), a traditional antirheumatic herb, have been reported to have immunomodulatory effects on both cell-mediated and humoral immunity in vitro, but little is known about the mode of action in vivo. The objective of this study was therefore to evaluate the efficacy of Fun-boi against arthritis and its effect on the immune system.Mice were divided into the following 3 groups of 7 mice each: 1) a normal group, not treated to cause collagen-induced arthritis (CIA), received water orally; 2) a control group with CIA received water orally; and 3) the Fun-boi group with CIA, received Fun-boi (3 mg/g body weight/day) orally. We analyzed the arthritis score, the serum anti-type II collagen (CII) antibody level, and the percentage of the following lymphocyte subsets from lymphoid organs: B220, CD3/CD4, CD3/CD8 and CD40L/CD4 lymphocytes from blood or lymph nodes; and CD4-CD8-, CD4+CD8+, CD4+CD8- and CD4-CD8+ from the thymus.Fun-boi therapy markedly reduced the severity of arthritis (p0.001) and tended to reduce the serum anti-CII antibody level (p = 0.06). Whereas CII immunization of DBA/1J mice caused a significant redistribution of CD3/CD8 lymphocytes from blood or lymph nodes, Fun-boi therapy caused significant normalization of the same types of lymphocyte subsets from lymph nodes, but did not affect the CD4 or CD4/CD40L lymphocyte subsets.These results demonstrate that Fun-boi therapy exerts therapeutic effects in CIA mice, possibly by causing immunomodulatory effects at specific sites.

In this paper, we report the difference in absorption spectrum that has a close relation to photosensitivity and the improvement of the quality by thermal annealing between two Ge-doped SiO/sub 2/ planar waveguides synthesized by different methods.

In 1997, four dosimeter packages, each of which contains two CR-39 plates and 18 TLDs (Mg 2 SiO 4 :Tb), were placed inside the MIR Space Station and flew on an orbit with an inclination angle of 51.6° and an altitude of approximately 400 km for 40 days. We estimated the absorbed doses, dose equivalents and effective quality factors during the flight by combining CR-39 data and TLD data. We then compared these results to those obtained with the same analysis method from the dosimeter packages on board Space Shuttle missions STS-79, -84 and -91 that flew along the same orbit. Finally, the differences between our results and those obtained by another group using passive dosimeters on the MIR are discussed.

We have investigated D-fraction (MDF) extracted from Grifola frondosa (Maitake mushroom) on the inducible nitric oxide synthase (iNOS)-mediated nitric oxide (NO) production in RAW264.7 (RAW) cells, a murine monocyte/macrophage cell line, with special reference to antitumor activity of MDF against human hepatoma-derived huH-1 cells. MDF could induce iNOS mRNA expression in RAW cells in a dose range of more than 30 microg/ml, but the effect of 10 microg/ml of MDF was negligible. The iNOS mRNA expression induced by 100 microg/ml of MDF was 6 hrs later, but lasted for a longer time than that of lipopolysaccharide (LPS), a representative iNOS inducer. Although iNOS mRNA levels in MDF-stimulated cells were almost equal to LPS-stimulated cells at the peak time, the cumulative amount of nitrite was only about 50% compared with that of LPS-treated cells. When huH-I cells were cultured in MDF containing media in a 24-well plate with inserted porous bottom in the presence or absence of RAW cells, the viability of huH-1 cells decreased significantly only in the presence of RAW cells in MDF dose-dependent manner. This antitumor activity of RAW cells in the presence of MDF was abolished or attenuated by the addition of L-NAME, a NOS inhibitor, confirming that this phenomenon is due to iNOS-mediated NO production by RAW cells, but not direct cytotoxic activity of MDF against huH-1 cells. These data suggest that MDF is a novel inducer for iNOS which contributes at least in part to antitumor activity of MDF.

Dosimetric measurements on the Space Shuttle Missions STS-84, -89 and -91 have been made by the real-time radiation monitoring device III (RRMD-III). Simultaneously, another dosimetry measurement was made by the Dosimetry Telescope (DOSTEL) on STS-84 and by the tissue-equivalent proportional counter (TEPC) on STS-91. First, the RRMD-III instrument is described in detail and its results summarized. Then, the results of DOSTEL and TEPC are compared with those of the RRMD-III. Also, the absorbed doses obtained by TLD (Mg2SiO4) and by RRMD-III on board STS-84 and -91 are compared.

A total of 23 newly-synthesized 2-aminomethylene-3(2H)-benzofuranone and structurally-related compounds were compared for their cytotoxic activity against both normal (human gingival fibroblast HGF) and tumor cells (human oral squamous cell lines HSC-2, HSC-3 and human salivary gland tumor cells HSG). There was a significant variability of drug sensitivity among the oral tumor cell lines. In general, HSC-2 cells were the most sensitive, followed by HSG cells, while HSC-3 cells were the most resistant. HGF normal cells were highly resistant to all compounds, suggesting their tumor-specific cytotoxic action. The cytotoxic activity of the compounds with morpholine, 1-methylpiperazine or piperidine structure was generally elevated by the introduction of fluorine, but not chlorine and methoxy functional groups, to the benzofuranone structure, whereas that of compounds attached by 1-phenylpiperazine or 1-(2-pyridyl)piperazine was rather reduced. The most active compounds induced internucleosomal DNA fragmentation in human promyelocytic leukemia HL-60 cells, but not in HSG, further confirming that oral tumor cell lines are resistant to DNase digestion.

The LET distributions during the Space Shuttle missions STS-84 (altitude 270– 412 km , average 375 km ; inclination angle, 51.6°) and STS-91 (altitude 328– 397 km , average 373 km ; inclination angle, 51.6°) were measured using CR-39 plastic nuclear track detectors. A correction for the dip-angle dependence of the track-formation sensitivity of the CR-39 plates was applied to the data analysis. The absorbed doses and the dose equivalents around RRMD Detector Units, estimated from the LET distributions in the LET region of 4– 200 keV / μm , fluctuated with standard deviations of ±21% to ±35% in both flight experiments. The LET distributions obtained from the CR-39 plates agreed well with that obtained from RRMD-II in STS-91. However, the particle fluxes obtained from RRMD-III in STS-84 and STS-91 were two or three times higher than those obtained from RRMD-II and the CR-39 plates. It was concluded that the LET distributions obtained from RRMD-II and the CR-39 plates in the present flight experiments did not include the contribution of target-fragmented secondary heavy particles produced by low-LET particles, such as relativistic or semi-relativistic protons and helium ions, whereas RRMD-III was able to detect these secondary particles because of its low triggering level.