Pathogenic Potential of Eomesodermin-Expressing T-Helper Cells in Neurodegenerative Diseases.

Eomesodermin-expressing (Eomes+) T-helper (Th) cells show cytotoxic characteristics in secondary progressive multiple sclerosis. We found that Eomes+ Th cell frequency was increased in the peripheral blood of amyotrophic lateral sclerosis and Alzheimer's disease patients. Furthermore, granzyme B production by Th cells from such patients was high compared with controls. A high frequency of Eomes+ Th cells was observed in the initial (acutely progressive) stage of amyotrophic lateral sclerosis, and a positive correlation between Eomes+ Th cell frequency and cognitive decline was observed in Alzheimer's disease patients. Therefore, Eomes+ Th cells may be involved in the pathology of amyotrophic lateral sclerosis and Alzheimer's disease. ANN NEUROL 2024;95:1093-1098.

Migration, residency and habitat utilisation by wild and cultured Japanese eels (Anguilla japonica) in a shallow brackish lagoon and inflowing rivers using acoustic telemetry.

This study monitored post-release movements of 20 wild Japanese eels (Anguilla japonica) [mean ± S.D. 520.8 ± 92.3 mm total length (TL), 217.9 ± 146.3 g body mass (BM)] in a brackish water lagoon in northeastern Japan using acoustic telemetry to elucidate how wild Japanese eels use different river, estuary and marine environments. In addition, 12 cultured Japanese eels (TL = 578.9 ± 18.0 mm, BM = 344.9 ± 25.5 g) were released to understand the comparative behaviours of wild and cultured eels. Both types of eels were simultaneously released in the southern inner part of the lagoon in September 2016 where there are freshwater influences from a river. Following release, eight of the wild eels (40%) were largely sedentary near the released point (river mouth) and stayed at the site for overwinter. Nonetheless, several individuals showed behavioural plasticity of habitat use: three wild eels moved towards the northern part of the lagoon with stronger influence from the sea during May-July 2017. Two wild eels showed clear repeated movements from the lagoon to a river at night and returned to the lagoon by dawn for more than a week every day, and one wild eel migrated upstream for overwintering. Signals from 55% of the wild eels could be detected for more than 6 months, whereas those from all of the cultured eels were lost by December 2016, indicating a short resident time of large cultured eels (BM > 200 g) released in a brackish water area. One wild silver eel migrated to the outer sea during the ebb tide at night in November 2016, probably triggered by the decrease in water temperature (from c. 20°C to c. 13°C), and seven cultured eels similarly moved to the outer sea during October-November 2016. The results revealed the similarities (e.g., nocturnal movements) and differences (e.g., stay period and seasonal movements) in the behavioural characteristics of wild and cultured eels and indicated that habitat connectivity among river, estuary and coastal waters is crucial for enabling eels to efficiently utilise these productive habitats through their behavioural plasticity.

[A case of hypoxic encephalopathy with unilateral laminar necrosis].

We reported a 67-year-old woman with unilateral laminar necrosis caused by hypoxic encephalopathy. She presented with sudden onset of dyspnea, unconsciousness and left hemiplegia. Although diffusion-weighted MRI image of the brain 14 hours after onset was indistinct, MRI on the 4th day showed right laminar necrosis. Cerebral angiography demonstrated complete obstruction of the right proximal common carotid artery and severe stenosis of the left internal carotid artery. We speculate that chronic ipsilateral obstruction of the internal carotid artery may modify the unique distribution of laminar necrosis. As shown in this case, laminar necrosis can be demonstrated only on subsequent MRI. If clinical suspicion of hypoxic encephalopathy is high, repeated MRI may be appropriate.

Effects of the nuclear disaster on marine products in Fukushima: An update after five years.

Original data (134Cs and 137Cs, and sampling location) of marine products in Fukushima Prefecture monitored during 2011-2015 (n = 32,492) were analyzed to present an updated detailed description of radiocesium contamination after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident and to examine taxon/habitat-specific decreasing trends in different areas. Furthermore, marine species data presented by the Tokyo Electric Power Company (TEPCO) during 2012-2015 (n = 5458) were analyzed to evaluate the decreasing trends of 137Cs inside and outside (within a 20 km radius) of the FDNPP port. Monitoring results by Fukushima Prefecture show that percentages of samples higher than the Japanese regulatory limit of 100 Bq kg-1-wet (>RL%) were higher, whereas those below the detection limit (RL% and

Pathophysiological studies of trinitrobenzene sulfonic acid-induced colitis in Syrian hamsters (Mesocricetus auratus).

We developed a colitis model in Syrian hamsters (Mesocricetus auratus) to investigate the relationship between colitis and neutrophil elastase (NE). Colitis was induced by a single intracolonic dose of trinitrobenzene sulfonic acid (TNBS; 90 mg/ml) dissolved in 15% (vol/vol) ethanol. The ulcer area, tissue myeloperoxidase (MPO) activity, and luminal NE activity all were increased on Days 1 and 5, corresponding with the acute inflammatory histopathological changes. These acute inflammatory parameters subsequently decreased by Day 14, and chronic inflammatory histopathological changes became evident. Recurrence of inflammation was not observed during the period up to Day 28. To evaluate our colitis model, the effects of prednisolone were examined. Prednisolone was administered orally once on the day before induction of colitis, and animals were treated twice daily thereafter. Although prednisolone had little effect on the tissue MPO activity, prednisolone inhibited the ulcer area and NE activity. In addition, the effects of an NE-specific inhibitor (ONO-6818) on our TNBS-induced colitis model were examined. In the subcutaneous treatment study, ONO-6818 was administered once before the induction of colitis. Although ONO-6818 had little effect on the tissue MPO activity, the ulcer area and NE activity were decreased in the ONO-6818-treated group. The inhibitory effects on the ulcer area and NE activity were confirmed after oral treatment with ONO-6818 after induction of colitis. We conclude that our colitis model is useful for investigating the relationship between colitis and NE, and inhibition of NE activity can prevent the progression of ulceration.

Comparison of paralytic shellfish poisoning toxin between carnivorous crabs (Telmessus acutidens and Charybdis japonica) and their prey mussel (Mytilus galloprovincialis) in an inshore food chain.

Paralytic shellfish poisoning toxin in two shore crab species, Telmessus acutidens and Charybdis japonica, were compared with the toxin in the prey mussel Mytilus galloprovincialis and causative dinoflagellates Alexandrium tamarense, all having been collected at Onahama, Fukushima Prefecture, in the northern part of Japan. When the toxicities were detected in mussels by mouse bioassays, 73.7% of the sampled T. acutidens were toxic in the hepatopancreas. T. acutidens has been found to become toxic for three years, therefore, it can be concluded that the crab commonly and repeatedly accumulate the toxins via the food chain at Onahama. C. japonica was also expected to be a possible vector species, because small quantities of the toxins were detected in eight specimens of the crab by HPLC analysis. By the comparison of the toxin profiles in the dinoflagellates, mussels and the crab T. acutidens, reductive conversions of GTX1 and GTX4 were observed when the toxins passed through the three species in the food chain. But increases of STX and neoSTX by further reductive process were not observed in the crab. The absence of the STX group toxins in the crab suggests that the crab eliminates the toxin before such reductive process occur.

Accumulation of paralytic shellfish poisoning toxins in the edible shore crab Telmessus acutidens.

Several shellfishes including the crab Telmessus acutidens and its prey bivalve Mytilus galloprovincialis were collected at Onahama in Japan to investigate the accumulation of paralytic shellfish poisoning (PSP) toxins during the blooming season of toxic dinoflagellates. The toxicity of the viscera of T. acutidens collected in 1999 was 30.0 and 80.0 MU/g, and that of M. galloprovincialis was 9.6 MU/g by mouse bioassay. PSP toxins in the crab viscera were identified by HPLC-FLD and ESI-MS, so this is the first observation of PSP toxins in T. acutidens. Carbamate toxins (GTX1-4, and STX) were the major component in the crab as well as in the mussels, and accounted for over 60% on a molar basis. However, the ratio of the N1-OH toxin to N1-H toxin of the crabs were largely different from that of the mussels, and a reductive conversion of the toxins in T. acutidens is concluded as the probable cause. In 2000, PSP toxins were also detected in both crabs and mussels, though the contents were very low compared with the levels observed in 1999. The difference in the toxin abundance suggests that the toxin content in the crab was affected by those of the prey.

Colonic ulceration and increase of neutrophil elastase activity in the acetic acid-induced colitis model in Syrian hamsters.

A novel colitis model using Syrian hamsters was developed. Colitis was induced by intracolonic administration of 1% acetic acid, and the ulcer area, tissue myeloperoxidase (MPO) activity, and luminal neutrophil elastase (NE) activity of the colon were determined at 1, 3, 8, 24 and 48 hr after colitis induction. The histopathological changes of the colon were also examined in this model. An increase of tissue MPO activity and NE activity was evident at 3 hr after induction of colitis, peaked at 24 hr, and decreased subsequently. The increase of luminal NE activity was well correlated with the colonic ulcer area. In histopathological examination, ulceration, erosion, crypt abscesses, neutrophil infiltration, hemorrhage, and edema were seen. The effects of prednisolone were examined to evaluate the adequacy of our colitis model. Syrian hamsters were treated orally with prednisolone at 18 and 1 hr before and at 6 hr after induction of colitis, and the ulcer area, tissue MPO activity, and luminal NE activity were evaluated at 24 hr after colitis induction. Prednisolone therapy had little effect on the tissue MPO activity. However, the NE activity of the prednisolone-treated group was significantly decreased. In addition, although prednisolone did not significantly decrease the ulcer area, a tendency toward decrease was noted. We conclude that this new model of experimental colitis in Syrian hamsters is useful for investigating the pathophysiology of colitis, especially useful for studying the relationship between colitis and NE activity.

Effects of the neutrophil elastase inhibitor (ONO-6818) on acetic acid induced colitis in Syrian hamsters.

Neutrophil elastase (NE) released from neutrophils during inflammation is related to tissue disturbance and organ failure. We investigated the effects of an orally active NE inhibitor, ONO-6818, on acetic acid induced colitis in Syrian hamsters. The ulcer area, hemoglobin level in the colonic lumen, NE activity, and tissue myeloperoxidase (MPO) activity in the colitis control animals were significantly increased compared to the normal control ones. Either oral or subcutaneous treatment with ONO-6818 had significant inhibitory effects on the ulcer area, hemoglobin level and NE activity in the colonic lumen, but ONO-6818 did not have a significant inhibitory effect on tissue MPO activity. We conclude that NE is closely related to the development of inflammation in acetic acid-induced colitis in Syrian hamsters and that the condition is improved by the inhibition of NE.

Role of nitric oxide in hemodialysis-related hypotension in an experimental renal dysfunction dog model.

To clarify the role of nitric oxide (NO) in hemodialysis (HD)-related hypotension, the relationship between plasma NO metabolites (NOx) and blood pressure changes, and the effect of N(G)-monomethyl-L-arginine (L-NMMA), a NO synthase inhibitor, on changes in blood pressure were evaluated in an experimental renal dysfunctional dog model. In order to create a renal dysfunction model, gentamicin was administered to male beagles in which 7 of 8 renal artery branches had been ligated. Normal renal functional and dysfunctional dogs underwent 3 hr of HD per day for 3 days. HD induced a transient decrease in mean blood pressure in the normal renal functional dogs. In renal dysfunctional dogs, a continuous hypotension occurred with a gradual increase in the plasma NOx concentration during HD. Although L-NMMA prevented the fall in blood pressure, it did not significantly change the plasma NOx concentration during HD. These results suggest that NO contributes to HD-related hypotension in renal dysfunctional dogs but the plasma NOx concentration does not reflect the change in blood pressure.

[The utility of voxel-based morphometry in the diagnosis of spinocerebellar degeneration].

We evaluated atrophic sites in the brainstem and cerebellum in the patients with spinocerebellar degeneration by using voxel-based morphometry (VBM). Gray matter atrophy was found extensively in both the cerebellar hemispheres and vermis of subjects presenting the cerebellar variant of multiple system atrophy (MSA-C; n=9). In addition, remarkable white matter atrophy was observed in the middle cerebellar peduncle, brainstem, and cerebellar hemispheres. In contrast, gray matter atrophy was not apparent in the cerebellar hemispheres or vermis of subjects in the SCA3 group (n=6), whereas intense white matter atrophy was visible in the middle cerebellar peduncle, brainstem, and cerebellar hemispheres. White matter atrophy was also observed in the brainstem and surrounding the dentate nucleus in both cases of dentatorubral-pallidoluysian atrophy (DRPLA) (n=2), whereas gray matter atrophy of the cerebellum was not remarkable. In both the SCA6 group (n=3) and the SCA31 group (n=2), gray matter atrophy was prominent in the cerebellar hemispheres and vermis; however, white matter atrophy was not found in the middle cerebellar peduncle and brainstem, whereas symmetric atrophy of white matter was found in the vicinity of the dentate nucleus. In each of these diseases, VBM findings were consistent with the pathological findings; therefore, VBM can be considered a useful tool for the diagnosis of spinocerebellar degeneration.

Distribution of local 137Cs anomalies on the seafloor near the Fukushima Dai-ichi Nuclear Power Plant.

An estimated 3.5±0.7×10(15) Bq of (137)Cs is thought to have been discharged into the ocean following the melt down at Fukushima Dai-ichi Nuclear Power Plant (F1NPP). While efforts have been made to monitor seafloor radiation levels, the sampling techniques used cannot capture the continuous distribution of radionuclides. In this work, we apply in situ measurement techniques using a towed gamma ray spectrometer to map the continuous distribution of (137)Cs on the seafloor within 20 km of the F1NPP. The results reveal the existence of local (137)Cs anomalies, with levels of (137)Cs an order of magnitude higher than the surrounding seafloors. The sizes of the anomalies mapped in this work range from a few meters to a few hundreds of meters in length, and it is demonstrated that the distribution of these anomalies is strongly influenced by meter scale features of the terrain.

Effects of the nuclear disaster on marine products in Fukushima.

After the release of huge amounts of radionuclides into the ocean from the devastated Fukushima Dai-ichi Nuclear Power Plant (FDNPP), safety concerns have arisen for marine products in Fukushima Prefecture. As of October 2012, we had inspected the radionuclide ((131)I, (134)Cs and (137)Cs) concentrations in 6462 specimens within 169 marine species collected off the coast of Fukushima Prefecture from April 2011. Only two species exceeded the Japanese provisional regulatory limit for (131)I (2000 Bq/kg-wet) immediately after the FDNPP accident. In 2011 and 2012, 63 and 41 species respectively exceeded the Japanese regulatory limit for radioactive Cs (100 Bq/kg-wet). The overall radioactive Cs concentrations of the total marine products have decreased significantly. However, the time-series trends of radioactive Cs concentrations have differed greatly among taxa, habitats (pelagic/demersal), and spatial distributions. Higher concentrations were observed in shallower waters south of the FDNPP. Radioactive Cs concentrations decreased quickly or were below detection limits in pelagic fishes and some invertebrates, and decreased constantly in seaweed, surf clams, and other organisms. However, in some coastal demersal fishes, the declining trend was much more gradual, and concentrations above the regulatory limit have been detected frequently, indicating continued uptake of radioactive Cs through the benthic food web. The main continuing source of radioactive Cs to the benthic food web is expected to be the radioactive Cs-containing detritus in sediment. Trial fishing operations for several selected species without radioactive Cs contamination were commenced in Soma area, 50 km north of the FDNPP, from June 2012. Long-term and careful monitoring of marine products in the waters off Fukushima Prefecture, especially around the FDNPP, is necessary to restart the coastal fishery reliably and to prevent harmful rumors in the future.

Effects of a selective inhibitor of inducible nitric oxide synthase, ONO-1714, on experimental hemodialysis-related hypotension in renal dysfunctional dogs.

The effect of a selective inducible nitric oxide synthase inhibitor, ONO-1714 ((1S,5S,6R,7R)-7-chloro-3-imino-5-methyl-2-azabicyclo[4.1.0]heptane hydrochloride), on hemodialysis-related hypotension was investigated using a canine model of renal dysfunction. Renal dysfunction was induced in dogs by complete bilateral ligation of renal arteries. On performing hemodialysis with ultrafiltration, the blood pressure of the renal dysfunction dogs gradually decreased and persisted at reduced levels until completion. ONO-1714 ameliorated the hemodialysis-induced hypotension in the renal dysfunction dogs at a dose that did not influence blood pressure in non-hemodialysis dogs with normal renal function. The above findings indicated that ONO-1714 may elicit beneficial effects on hemodialysis-related hypotension.

A clinical and genetic study in a large cohort of patients with spinocerebellar ataxia type 6.

In order to clarify the clinical and genetic features of SCA6, we retrospectively analyzed 140 patients. We observed an inverse correlation between the age of onset and the length of the expanded allele, and also between the age of onset and the sum of CAG repeats in the normal and the expanded alleles. The ages of onset of four homozygous patients correlated better with the sum of CAG repeats in both alleles rather than with the expanded allele calculated from heterozygous SCA6 subjects. Clinically, unsteadiness of gait was the main initial symptom, followed by vertigo and oscillopsia, and cerebellar signs were detected in nearly 100% of the patients. In contrast, extracerebellar signs were relatively mild and infrequent. The results of neuro-otological examination performed in 22 patients suggested the purely cerebellar abnormalities of ocular movements in nature. There was a close relationship between downbeat positioning nystagmus (DPN) and positioning vertigo, which became more common in the later stage. We conclude that total number of CAG repeat-units in both alleles is a good parameter for assessment of age of onset in SCA6 including homozygous patients. In addition, clinical and neuro-otological examinations suggested that SCA6 is a disease with predominantly cerebellar dysfunction.