Feasibility of using 236U to reconstruct close-in fallout deposition from the Hiroshima atomic bomb.

The first results on the feasibility of using (236)U to reconstruct the level and spatial distribution of close-in fallout deposition from the Hiroshima A-bomb are reported, coupled with the use of global fallout (137)Cs and (239+240)Pu. The results for global fallout (236)U in soil samples (0-30cm) from Ishikawa prefecture showed that the deposition density of (236)U from the global fallout can be accurately evaluated using AMS. All deposited (236)U, (137)Cs and (239+240)Pu appeared to have been recovered using 30-cm cores. It was also noted from the depth profiles for (236)U/(239+240)Pu and (236)U/(137)Cs ratios that the downward behavior of (236)U in the soil was apparently similar to that of (239+240)Pu, while the (137)Cs was liable to be retained in upper layers compared with (236)U and (239+240)Pu. The accumulated levels were 1.78×10(13)atomsm(-2) for (236)U, 4340Bqm(-2) for (137)Cs and 141Bqm(-2) for (239+240)Pu. The ratios of (236)U/(137)Cs and (236)U/(239+240)Pu were (4.10±0.12)×10(9) and (1.26±0.04)×10(11)atomsBq(-1), respectively. Results of (236)U, (137)Cs and (239+240)Pu measurements for the seven soil cores (0-30cm) from Hiroshima were discussed on the basis of ratios of (236)U/(137)Cs and (236)U/(239+240)Pu by comparing with those from the background area in Ishikawa, indicating that the global fallout dominates the current level of (236)U accumulation in soil in the Black-rain area around Hiroshima after the Hiroshima bomb, and the contribution of the close-in fallout (236)U produced by the Hiroshima A-bomb seems difficult to observe.

Impairment of conditioned freezing to tone, but not to context, in Fyn-transgenic mice: relationship to NMDA receptor subunit 2B function.

We previously demonstrated that transgenic mice overexpressing Fyn tyrosine kinase exhibit higher seizure susceptibility and enhanced tyrosine phosphorylation of several proteins, including the N-methyl-D-aspartate (NMDA) receptor subunit 2B (NR2B). In the present study, we analysed behavioural phenotypes, especially conditioned fear responses, of Fyn-transgenic (TG) mice to better understand the role of Fyn in learned emotional behaviour. Tone-dependent conditioned freezing was significantly attenuated in Fyn-TG mice, whereas context-dependent freezing was unaffected. Neither massed nor spaced conditioning ameliorated the attenuation of tone-dependent freezing. However, the selective NR2B antagonist ifenprodil, when administered before conditioning, restored tone-dependent freezing in Fyn-TG mice at a dose that did not affect freezing in wild-type (WT) mice. These results suggest that impairment of tone-dependent conditioned freezing in Fyn-TG mice is caused by disruption of the NR2B-containing NMDA receptor function. Tyrosine phosphorylation of brain proteins, including NR2B, was enhanced in Fyn-TG mice compared with that in WT mice. We also found that ifenprodil significantly suppressed the enhanced tyrosine phosphorylation. Thus, our data support the notion that NMDA receptor activity is tightly correlated with protein tyrosine phosphorylation, and Fyn might be one key molecule that controls tone-dependent conditioned freezing through the regulation of NMDA receptor function.

Dose distributions in a human head phantom for neutron capture therapy using moderated neutrons from the 2.5 meV proton-7Li reaction or from fission of 235U.

The feasibility of neutron capture therapy (NCT) using an accelerator-based neutron source of the 7Li(p,n) reaction produced by 2.5 MeV protons was investigated by comparing the neutron beam tailored by both the Hiroshima University radiological research accelerator (HIRRAC) and the heavy water neutron irradiation facility in the Kyoto University reactor (KUR-HWNIF) from the viewpoint of the contamination dose ratios of the fast neutrons and the gamma rays. These contamination ratios to the boron dose were estimated in a water phantom of 20 cm diameter and 20 cm length to simulate a human head, with experiments by the same techniques for NCT in KUR-HWNIF and/or the simulation calculations by the Monte Carlo N-particle transport code system version 4B (MCNP-4B). It was found that the 7Li(p,n) neutrons produced by 2.5 MeV protons combined with 20, 25 or 30 cm thick D20 moderators of 20 cm diameter could make irradiation fields for NCT with depth-dose characteristics similar to those from the epithermal neutron beam at the KUR-HWNIF.

Effects of vitamin B12 on bright light on cognitive and sleep-wake rhythm in Alzheimer-type dementia.

The present study investigated the effects of vitamin B12 (VB12) on circadian rhythm in Alzheimer-type dementia (ATD). Twenty-eight ATD patients were treated with bright light therapy (BLT) for 8 weeks. For the latter 4 weeks, half were treated with VB12 with BLT (BLT + VB12). We evaluated the cognitive state with Mini-Mental State Examination and the circadian rhythm with actigraphy after the fourth and eighth week. After the first 4 weeks BLT improved the circadian rhythm disturbances and cognitive state especially in the early stage of ATD. Although the latter 4 week-BLT caused no significant effects on the circadian rhythm; BLT + VB12 improved the vigilance level during the daytime. These results suggest that VB12 has some efficiency to enhance vigilance for ATD patients.

Functional analysis of tobacco LIM protein Ntlim1 involved in lignin biosynthesis.

The AC-rich motif, Pal-box, is an important cis-acting element for gene expression involved in phenylpropanoid biosynthesis. A cDNA clone (Ntlim1) encoding a Pal-box binding protein was isolated by Southwestern screening. The deduced amino acid sequence is highly similar to the members of the LIM protein family that contain a zinc finger motif. Moreover, Ntlim1 had a specific DNA binding ability and transiently activated the transcription of a beta-glucuronidase reporter gene driven by the Pal-box sequence in tobacco protoplasts. The transgenic tobacco plants with antisense Ntlim1 showed low levels of transcripts from some key phenylpropanoid pathway genes such as phenylalanine ammonia-lyase, hydroxycinnamate CoA ligase and cinnamyl alcohol dehydrogenase. Furthermore, a 27% reduction of lignin content was observed in the transgenic tobacco with antisense Ntlim1.

Effects of bright light on cognitive and sleep-wake (circadian) rhythm disturbances in Alzheimer-type dementia.

Twenty-seven patients with Alzheimer-type dementia (ATD) were treated with bright light therapy in the morning for four consecutive weeks. The cognitive state of each patient was evaluated with the Mini-Mental-State Examination (MMSE) and circadian rhythm with actigram before and after therapy for all of the patients and those of two groups divided by the severity criteria of the Clinical Dementia Rating. The therapy improved the circadian rhythm disturbances. Although the therapy caused no remarkable effects on dementia severity, it improved the MMSE scores, especially in the early stages of ATD. These results suggest that bright light therapy improved the circadian rhythm disturbances and then bettered the cognitive state in early-stage ATD.

[Effects of bright light on cognitive disturbances in Alzheimer-type dementia].

We investigated the effectiveness of bright light therapy on cognitive disturbances and its effect on circadian (sleep-wake) rhythm in Alzheimer-type dementia (ATD). Twenty-seven patients with ATD were treated with bright light therapy in the morning for 4 consecutive weeks. We evaluated the cognitive functions and circadian rhythms of the patients as a whale, and as members of two groups (one: questionable and mild dementia: the other: moderate and severe dementia; both groups classified by the severity criteria of Clinical Dementia Rating). We assessed circadian rhythms by actigraphy and cognitive states by Mini-Mental-State Examination (MMSE) and Alzheimer's Disease Assessment Scale (ADAS) before and after light therapy. Bright light therapy improved circadian rhythm. Although bright light therapy had no Significant effect on the Severity of dementia, it improved the MMSE scores, cognitive functions of ADAS scores (memory > language) and non-cognitive functions of ADAS scores (behavior = mood), especially in the questionable and mild dementia group. These results suggest that bright light therapy improves cognitive functions with the modification of circadian rhythm, especially in the early stages of ATD.

Argatroban, an attractive anticoagulant, for left heart bypass with centrifugal pump for repair of traumatic aortic rupture.

Systemic heparinization often increases the risk of fatal bleeding from other injured organs in surgical repair of the aorta using extracorporeal circulation in patients with traumatic aortic rupture associated with multisystem injuries. We used an antithrombin agent, argatroban, as an alternative anticoagulant in left heart bypass with the Bio-Medicus centrifugal pump in 7 of 9 recent patients who underwent aortic repair using left heart bypass. All these patients survived without obvious evidence of systemic thromboembolization. Surgical treatments for other organ injuries were carried out in 3 patients concomitantly or immediately after aortic repairs without undue blood loss. Argatroban may have a complementary effect for preventing thrombus formation without aggravating bleeding tendency because of its monotarget specificity to thrombin. We believe intravenous administration (0.5 to 2 micrograms/kg/min) of argatroban is a safe anticoagulant for left heart bypass in repairs of traumatic aortic rupture associated with multiple organ injuries.

Dose estimations of fast neutrons from a nuclear reactor by micronuclear yields in onion seedlings.

Irradiations of onion seedlings with fission neutrons from bare, Pb-moderated, and Fe-moderated 252Cf sources induced micronuclei in the root-tip cells at similar rates. The rate per cGy averaged for the three sources, , was 19 times higher than rate induced by 60Co gamma-rays. When neutron doses, Dn, were estimated from frequencies of micronuclei induced in onion seedlings after exposure to neutron-gamma mixed radiation from a 1 W nuclear reactor, using the reciprocal of as conversion factor, resulting Dn values agreed within 10% with doses measured with paired ionizing chambers. This excellent agreement was achieved by the high sensitivity of the onion system to fast neutrons relative to gamma-rays and the high contribution of fast neutrons to the total dose of mixed radiation in the reactor's field.

Early potentials of direct cortical responses: experimental study in dogs and pathophysiological and clinical implications.

OBJECTIVE: The characteristics of the early component of the direct cortical response have not been well studied, although direct cortical response recording is a common method of brain function monitoring. METHODS: In this experimental study, we sought conditions affording the clearest recording of the early potential, by varying the polarity and low-cutoff filter setting, and we confirmed that the early potential consists of two components, P1 and P2. RESULTS: When subcortical damage was induced by local cerebral compression or saline injection, transient changes in P1 and permanent disappearance of P2 were observed. P2 also disappeared when the fiber connections between the cortex and the basal ganglia, including the thalamus, were destroyed by wire insertion. With deep recording, both P1 and P2 exhibited potential reversal at a level histologically confirmed to be in Layer V of the cortex. CONCLUSION: These findings suggest that P1 is a spike reflecting the activity of pyramidal cells evoked by electrical stimulation of the brain surface and that P2 is a potential arising in Layer V of the cortex and is related to afferent fibers from the thalamus. Recording of P2 may be useful for monitoring for subcortical damage.

[A case of Japanese B encephalitis with lesions of thalamus and substantia nigra revealed by MRI].

We report a 6-year-old girl with Japanese B encephalitis. The initial symptoms were high fever, headache and vomiting. On the second day of illness, she developed hemiconvulsion and was admitted to our hospital. Physical examination demonstrated a stiff neck. C-reactive protein elevated to 22.7 mg/dl. CSF examination showed a marked increase in the cell count (10,896/3 mm3). During the course of the treatment, she showed transient hemiparesis and dysphagia, followed by akinetic mutism lasting for about a month. The patient was left with severe cognitive and memory impairment and complex partial seizures but no motor dysfunction. Japanese B encephalitis was diagnosed by means of serological examination. Magnetic resonance imaging revealed cystic lesions in the medial and posterior thalamus and substantia nigra and severe atrophy of the hippocampus. Despite the involvement of substantia nigra, the patient had no parkinsonism. The cognitive impairment may in part be explained by the lesions in the medical and posterior thalamus.

Inhibitory action of (-)-epigallocatechin gallate on radiation-induced mouse oncogenic transformation.

The anticarcinogenic activity of a major component of green tea, (-) epigallocatechin gallate (EGCg) was examined by using the radiation-induced oncogenic transformation in C3H10T1/2 cells. EGCg substantially suppressed the radiation-induced transformation so that the transformation frequency with 15 microM of EGCg was reduced nearly to spontaneous levels. This effect of EGCg was in a dose-dependent manner and significant suppression of transformation was observed even in treatment of cells with 5 microM of EGCg concentration where the cytotoxicity was mild. The inhibitory effect of EGCg was maximal when it was present during the entire incubation period. However, neither treatment prior to nor concurrent with radiation was effective, suggesting that EGCg action is mainly involved in the promotional stage of C3H10T1/2 cell transformation.

[The origin and development of the herbal gardens of the Owari clan].

The early herbal garden of the Owari Clan was called Ofuke-Oyakuen. By careful reading of the "Illustration of the Honorable Herb Garden (OYakuen no Zu), it is pointed out that this garden might have been opened around 1562 when 39 species of herbs granted by Shogun Iemitsu were planted. This garden was enlarged in about 1684. We found that the well-known "Honorable Illustration of Former Herb Garden (Moto-oyakuen On-ezu)" was a drawing of a part of this enlarged herbal garden. On the other hand, in 1735 a new herbal garden, Oshitayashiki-oyakuen was opened for cultivation of Panax Shinseng. While this garden produced fair results at Panax cultivation, it was closed in 1869 at the Meiji Restoration. In the last days of the Tokugawa regime, herbalists of this garden had made original advances in natural history.

Diazepam-insensitive GABAA receptors in rat cerebellum and thalamus.

Three major populations of GABAA receptor binding sites are present in cerebellar membranes: diazepam-sensitive [3H]Ro15-4513 binding sites, diazepam-insensitive [3H]Ro15-4513 binding sites and high-affinity [3H]muscimol binding sites. All three populations contain a beta subunit as shown by immunoprecipitation with antibodies that recognize all beta subunits. The beta 3 subtype of beta subunit is contained in all three populations, but only a similar low fraction (< 20%) in each. Thus, the majority contain beta subunits other than beta 3 (beta 2 and beta 1) and beta 3 subunits are not selectively associated with nor lacking in any of the three binding populations. Antibodies to the gamma 2 subunit precipitated similar fractions of [3H]Ro15-4513, [3H]flunitrazepam and [3H]muscimol binding sites, showing that gamma 2 subunits are present in high-affinity muscimol binding isoforms, as well as a significant fraction of the diazepam-insensitive [3H]Ro15-4513 binding sites. Under conditions that identify the 56 kDa alpha 6 subunit on SDS-PAGE as the diazepam insensitive site of [3H]Ro15-4513 binding in cerebellum, no polypeptide showing diazepam-insensitive binding of [3H]Ro15-4513 could be photoaffinity-labeled in rat thalamus. These results suggest that alpha 4 subunits in the thalamus participate primarily in subunit combinations which bind muscimol but not any benzodiazepine site ligands.

Clostridial gas gangrene associated with congenital generalized lipodystrophy: report of a case.

Congenital generalized lipodystrophy (CGL) is a rare disease, the main symptoms of which are a reduction of systemic subcutaneous fat, characteristic facial features, hypertrichosis, and insulin-resistant diabetes. We report herein the unusual case of a 25-year-old man with CGL in whom gas gangrene developed, an association which has never before been encountered.

Establishment of human osteoblastic cells derived from periosteum in culture.

We isolated osteoblastic cells derived from human periosteum and established them in culture. Their growth depended on the presence of ascorbic acid, and the doubling time was 40 to 60 h. The requirement for ascorbic acid was used to high production of collagen. These cells produced mainly type I collagen and only small amounts of type III collagen determined by reducing sodium dodecyl sulfate SDS-polyacrylamide gel electrophoresis. The total collagen yield was about 10 mg from 2 X 10(7) cells. The cells could be continuously cultured in alpha-minimum essential medium supplemented with 10% fetal bovine serum for 18 to 40 population doubling levels, depending on the age of the donated periosteum. These cells have the ability to calcify when incubated with 2 mM alpha-glycerophosphate-Na2. Calcification as viewed by the naked eye appeared from Day 15 after treatment. Treatment with the active formed vitamin D3, 1, 25 dihydroxyvitamin D3 enhanced calcification significantly and stimulated osteocalcin production. By electron microscopy, cells with many projections on their surfaces showed well-developed rough endoplasmic reticulum and actinlike fibers, and larger numbers of lysosomes, mitochondria, and secretion granules. Many matrix vesicles, in which minerals were initially localized, and well-banded collagen fibrils were seen in the intercellular spaces. These observations demonstrate typical osteoblastic morphology. The above results indicate that cultured cells from human periostem are osteoblastic cells that have the capacity to differentiate into osteocytes and to deposit calcified minerals in response to 1,25 dihydroxyvitamin D3.

Neonatal meconium obstruction in the ileum without mucoviscidosis.

Two newborns with intestinal obstruction of the terminal ileum without mucoviscidosis were cured by Gastrografin enema. A further case of a premature infant showed, at autopsy, a large intestine containing normal meconium, but an ileum which was plugged with tenacious meconium containing PAS-positive and alcian blue-negative mucus. Our 3 cases were similar to cases of "meconium disease" reported by Rickham and of "meconium plug in the small intestine" reported by Emery. The primary cause of this disease lies in the large amount of PAS-positive mucus secreted from goblet cells of the ileal mucosa and the hypertrophy of lymph nodules in the ileal submucosa.