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Fragmentation of forest habitat has negative effects on arboreal mammals, compromising their natural dispersal and foraging movements. This paper describes an evolving series of mitigation measures aimed at creating cost-effective continuity pathways for arboreal mammals in Japan. The projects have focused on the endemic Japanese dormouse (Glirulus japonicus) a scarce, but popular and iconic species which provides an effective vehicle for environmental education and public engagement.

We report a 28-year-old male with dysferlinopathy, who has remained asymptomatic for 10 years from a rhabdomyolysis-like episode. He had been in good health since birth, but felt difficulty in walking after a month and a half of manual labor at 18 years old (at the year 2000). Rhabdomyolysis was suspected because of muscle weakness and elevated serum CK of 28,094U/L. He was hospitalized and his muscle weakness improved. He was referred to us, because his serum CK remained around 2,000U/L. Histological analysis of muscle, when anti-dysferlin antibody was unavailable, was not informative but later analysis at the age of 23 using preserved specimen showed loss of dysferlin immunoreactivity. Subsequently, a missense mutation (c.2997G>T) and a deletion (c.3373delG) of the dysferlin gene, both of which are common in Miyoshi myopathy in Japanese, were identified. He continuously showed hyper-CKemia, but no apparent muscle weakness emerged for more than ten years. Reports on asymptomatic dysferlinopathy over such a long duration are rare. This case may suggest that genetic factors, environmental factors such as intensity of work-load, or both, might affect the clinical course of dysferlinopathy. Further follow-up is necessary.

Y. Kawamoto, H. Ito, Y. Kobayashi, Y. Suzuki, I. Akiguchi, H. Fujimura, S. Sakoda, H. Kusaka, A. Hirano and R. Takahashi (2010) Neuropathology and Applied Neurobiology36, 331–344 HtrA2/Omi-immunoreactive intraneuronal inclusions in the anterior horn of patients with sporadic and Cu/Zn superoxide dismutase (SOD1) mutant amyotrophic lateral sclerosis Aims: HtrA2/Omi is a mitochondrial serine protease that promotes the apoptotic processes, but the relationship between HtrA2/Omi and amyotrophic lateral sclerosis (ALS) is still unknown. The purpose of the present study was to determine whether abnormal expression of HtrA2/Omi occurs in patients with ALS. Methods: We prepared autopsied spinal cord tissues from 7 control subjects, 11 patients with sporadic ALS (SALS) and 4 patients with Cu/Zn superoxide dismutase (SOD1)-related familial ALS (FALS). We then performed immunohistochemical studies on HtrA2/Omi using formalin-fixed, paraffin-embedded sections from all of the cases. Results: In the control subjects, the anterior horn cells were mildly to moderately immunostained with HtrA2/Omi. In the patients with SALS, strong HtrA2/Omi immunoreactivity was found in some skein-like inclusions and round hyaline inclusions as well as many spheroids, but Bunina bodies were immunonegative for HtrA2/Omi. In the patients with SOD1-related FALS, Lewy body-like hyaline inclusions were observed in three cases and conglomerate inclusions were observed in the remaining case, and both types of inclusions were intensely immunopositive for HtrA2/Omi. Conclusions: These results suggest that abnormal accumulations of HtrA2/Omi may occur in several types of motor neuronal inclusions in the anterior horn from SALS and SOD1-linked FALS cases, and that HtrA2/Omi may be associated with the pathogenesis of both types of ALS.

Parkinson's disease is a neurodegenerative disease associated with the degeneration of dopaminergic neurons in the substantia nigra. The PTEN-induced kinase 1 gene (PINK1) is responsible for recessive inherited familial Parkinson's disease (PARK6). Neither the function of PINK1 nor its role in the prevention of Parkinson's disease is fully understood. Gene disruption of PINK1 causes remarkably different phenotypes in animal models such as Drosophila melanogaster, zebrafish, and mouse, none of which recapitulate Parkinson's-disease-like symptoms. We established PINK1-gene-disrupted medaka fish. These mutant fish grew normally at first, then developed significant decrease in the frequency of spontaneous swimming movements in the late-adult stage. Although the mutants did not show any dopaminergic cell loss, the amount of 3,4-dihydroxyphenylacetic acid, a major metabolite of dopamine, decreased. Thus, PINK1 contributes to the maintenance of dopamine metabolism, even before the selective death of dopaminergic neurons. Our animal model is therefore a valuable tool to detect pathogenesis in Parkinson's patients in the early stages.

HtrA2/Omi is a mitochondrial serine protease that is released into the cytosol and promotes apoptotic processes by binding to several members of the inhibitors of apoptosis protein family. HtrA2/Omi knockout mice show a parkinsonian phenotype, and mutations in the gene encoding HtrA2/Omi have been identified as susceptibility factors for Parkinson disease (PD). These results suggest that HtrA2/Omi may be involved in the pathogenesis of PD. We performed immunohistochemical studies of HtrA2/Omi on brains from patients with alpha-synuclein-related disorders, including PD, dementia with Lewy bodies (DLB), and multiple-system atrophy (MSA); patients with other neurodegenerative diseases; and controls. HtrA2/Omi is expressed in normal brain tissue, and there was some anti-HtrA2/Omi immunostaining of neurons in normal brains as well as those with other neurodegenerative diseases. In PD and DLB brains, both classic (i.e. brainstem-type) and cortical Lewy bodies were intensely immunostained; pale bodies were also strongly immunopositive for HtrA2/Omi. In MSA brains, numerous glial cytoplasmic inclusions, neuronal cytoplasmic inclusions, and dystrophic neurites were also intensely immunoreactive for HtrA2/Omi. These results suggest that widespread accumulation of HtrA2/Omi may occur in pathologic alpha-synuclein-containing inclusions in brains with PD, DLB, or MSA and that HtrA2/Omi may be associated with the pathogenesis of alpha-synucleinopathies.

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by selective dopaminergic cell loss in the substantia nigra, but its pathogenesis remains unclear. The recessively inherited familial PD genes PARK2 and PARK6 have been attributed to mutations in the Parkin and PTEN-induced kinase 1 (PINK1) genes, respectively. Recent reports suggest that PINK1 works upstream of Parkin in the same pathway to regulate mitochondrial dynamics and/or conduct autophagic clearance of damaged mitochondria. This phenomenon is preserved from Drosophila to human cell lines but has not been demonstrated in a vertebrate animal model in vivo. Here, we developed a medaka fish (Oryzias latipes) model that is deficient in Pink1 and Parkin. We found that despite the lack of a conspicuous phenotype in single mutants for Pink1 or Parkin, medaka that are deficient in both genes developed phenotypes similar to that of human PD: late-onset locomotor dysfunction, a decrease in dopamine levels and a selective degeneration of dopaminergic neurons. Further analysis also revealed defects in mitochondrial enzymatic activity as well as cell death. Consistently, PINK1 and Parkin double-deficient MEF showed a further decrease in mitochondrial membrane potential and mitochondrial complex I activity as well as apoptosis compared with single-deficient MEF. Interestingly, these mitochondrial abnormalities in Parkin-deficient MEF were compensated by exogenous PINK1, but not by disease-related mutants. These results suggest that PINK1 and Parkin work in a complementary way to protect dopaminergic neurons by maintaining mitochondrial function in vertebrates.

PTEN-induced kinase 1 (PINK1), which is required for mitochondrial homeostasis, is a gene product responsible for early-onset Parkinson's disease (PD). Another early onset PD gene product, Parkin, has been suggested to function downstream of the PINK1 signalling pathway based on genetic studies in Drosophila. PINK1 is a serine/threonine kinase with a predicted mitochondrial target sequence and a probable transmembrane domain at the N-terminus, while Parkin is a RING-finger protein with ubiquitin-ligase (E3) activity. However, how PINK1 and Parkin regulate mitochondrial activity is largely unknown. To explore the molecular mechanism underlying the interaction between PINK1 and Parkin, we biochemically purified PINK1-binding proteins from human cultured cells and screened the genes encoding these binding proteins using Drosophila PINK1 (dPINK1) models to isolate a molecule(s) involved in the PINK1 pathology. Here we report that a PINK1-binding mitochondrial protein, PGAM5, modulates the PINK1 pathway. Loss of Drosophila PGAM5 (dPGAM5) can suppress the muscle degeneration, motor defects, and shorter lifespan that result from dPINK1 inactivation and that can be attributed to mitochondrial degeneration. However, dPGAM5 inactivation fails to modulate the phenotypes of parkin mutant flies. Conversely, ectopic expression of dPGAM5 exacerbated the dPINK1 and Drosophila parkin (dParkin) phenotypes. These results suggest that PGAM5 negatively regulates the PINK1 pathway related to maintenance of the mitochondria and, furthermore, that PGAM5 acts between PINK1 and Parkin, or functions independently of Parkin downstream of PINK1., Author Summary Parkinson's disease (PD) is a neurodegenerative disease pathologically characterized by degeneration of dopaminergic (DA) neurons in the midbrain. A small percentage of PD cases are inherited in a Mendelian manner, and several disease-causing genes have been identified. The PINK1 and Parkin genes have been isolated as the genes for autosomal recessive form of early-onset PD. Unexpectedly, loss of function of either PINK1 or Parkin in Drosophila causes mitochondrial degeneration in the flight muscles, which exhibits a visible phenotype of abnormal wing postures, allowing a rapid genetic screening. We purified PINK1-binding proteins from human cultured cells and screened the gene for these binding proteins using the PINK1 mutant flies. We found that inactivation of a PINK1-binding protein phosphoglycerate mutase 5 (PGAM5) suppresses mitochondrial degeneration caused by the loss of PINK1 activity. Although parkin is suggested to be genetically downstream of PINK1 in Drosophila, loss of PGAM5 failed to modulate the phenotypes by parkin inactivation. Our finding suggested that, for mitochondrial maintenance of tissues with high-energy demands such as the muscles and DA neurons, PGAM5 acts between PINK1 and Parkin, or functions independently of Parkin downstream of PINK1.

HtrA2/Omi is a mitochondrial serine protease that promotes apoptotic processes, and this study investigated whether the abnormal immunoexpression of HtrA2/Omi occurs in patients with Alzheimer's disease. We prepared autopsied brains from seven control individuals and seven patients with Alzheimer's disease, and then carried out immunohistochemical studies on HtrA2/Omi using formalin-fixed, paraffin-embedded sections from all of these cases. In the cerebral cortex and hippocampus from the cases of Alzheimer's disease, densely accumulated HtrA2/Omi immunoreactivity was scattered, both intracellularly and extracellularly. Double immunofluorescence analyses showed the partial localization of HtrA2/Omi immunoreactivity in amyloid β-peptide-immunopositive senile plaques and phosphorylated τ-immunopositive neurofibrillary tangles. These results suggest that HtrA2/Omi may be partially associated with the pathogenesis of Alzheimer's disease.

Leucine-rich repeat kinase 2 (LRRK2) is a key molecule in the pathogenesis of familial and idiopathic Parkinson’s disease (PD). We have identified two novel LRRK2-associated proteins, a HECT-type ubiquitin ligase, HERC2, and an adaptor-like protein with six repeated Neuralized domains, NEURL4. LRRK2 binds to NEURL4 and HERC2 via the LRRK2 Ras of complex proteins (ROC) domain and NEURL4, respectively. HERC2 and NEURL4 link LRRK2 to the cellular vesicle transport pathway and Notch signaling, through which the LRRK2 complex promotes the recycling of the Notch ligand Delta-like 1 (Dll1)/Delta (Dl) through the modulation of endosomal trafficking. This process negatively regulates Notch signaling through cis-inhibition by stabilizing Dll1/Dl, which accelerates neural stem cell differentiation and modulates the function and survival of differentiated dopaminergic neurons. These effects are strengthened by the R1441G ROC domain-mutant of LRRK2. These findings suggest that the alteration of Notch signaling in mature neurons is a component of PD etiology linked to LRRK2., Author Summary LRRK2 is linked to autosomal dominant late-onset Parkinson’s disease, suggesting that LRRK2 gain-of-function mutations lead to age-dependent degeneration of the midbrain dopaminergic neurons. In this study, we describe two novel LRRK2-associated proteins HERC2 and NEURL4, which are a ubiquitin ligase and an adaptor-like protein, respectively. HERC2 and NEURL4 direct LRRK2 to Notch signaling pathway, in which the LRRK2-NEURL4-HERC2 complex promotes the recycling of the Notch ligand Delta-like 1 (Dll1)/Delta (Dl) through the modulation of endosomal trafficking. As a result, the amounts of Dll1/D1 on the plasma membrane are increased, which affects negatively Notch signaling through cis-inhibition. The effect is enhanced by a Parkinson’s-disease associated mutation of LRRK2. Inhibition of Notch signaling in adult dopaminergic neurons impairs its functions and survival. These findings indicate a possible link between Notch pathway and Parkinson’s disease.

To examine the possible use of ceramics as key components for automotive gas turbines, studies were conducted on radial turbine rotors made of SN-88, a newly developed, heat resistant silicon nitride. The flexural strength of MOR bars cut from various portions of the rotor was measured, and three rotors were subjected to cold spin burst testing. Time dependent strength of the rotor at high temperatures was estimated by static fatigue rupture data of tensile test pieces at temperatures up to 1400°C for up to 1000hrs. The allowable stress at an arbitrary temperature and time to failure were explained well in terms of the Larson-Miller parameter. High temperature durability was also evaluated by hot-gas spin tests. The results of these tests suggest the possibility of fabricating reliable ceramic components which might enable the realization of ceramic gas turbine engines.

Microstructural degradation in two kinds of sintered silicon nitride due to high temperature exposure was examined on specimens after flexure static fatigue tests and room-temperature flexure tests of heated specimens. Surface oxidation layer was formed due to the reaction of silica formed by the oxidation of β-Si3N4 and sintering additives segregating from the interior grain boundary phase. Corresponding to the oxidation layer, a degraded layer containing numerous micro-pores resulting from the segregation of the sintering additives was formed just beneath the surface oxidation layer. The thickness of the surface oxidation layer, which was measured nondestructively by means of X-ray diffraction method, had increased along with the heating. Consequently, the room temperature strength of specimens after heating was considered to be related to the thicknesses of surface oxidation layer and surface degraded layer.

(I) Determination of insulin was examined by the rat-diaphragm method, and the following results were obtained: A linear regression was observed between extraglucose uptake and log-concentration of insulin in the range of 10 to 0.01mU/kg. The minimum detectable concentration was 0.003mU/ml, slope of regression line (regression coefficient) b=0.6610, standard deviation of regression line S=0.1674, index of precision λ=0.253 (intervals between consecutive doses, 10-fold).(II) Plasma insulin activity in 14 normal fasting dogs, estimated by this method was 0.347±0.184mU/ml. Change in plasma insulin activity was observed after administration of insulin, glucose and BZ 55 (N-sulfanylyl-N'-n-butyl-carbamide) with the following results:1. After intravenous administration of 1U/kg of insulin, plasma insulin activity increased from 0.229mU/ml before to 4.655m, U/ml at 10mins. became 0.645mU/ml at 30 mins. after.2. After subcutaneous administration of 0.2-0.8U/kg of insulin the results were as follows: In case of 0.2U/kg, plasma insulin activity always remained in the normal range; but in the case of 0.6U/kg, it increased significantly after the injection. The minimum dose of insulin in subcutaneous injection which produced increase in plasma insulin activity was 0.4U/kg.3. After the intravenous injection of 1g/kg of glucose, 0.347mU/ml before the injection became 0.933mU/ml at 30mins., indicating increase.4. After intraperitoneal administration of 50mg/kg of BZ 55, 0.287-0.382mU/ml before the injection became 0.180mU/ml at 1hr. and 2hrs. After the intravenous administration of 100mg/kg, 0.471mU/ml before the injection became 0.336mU/ml at 1hr., 0.283mU/ml at 2hrs. and 0.301mU/ml at 4 hrs. In all the cases, there was no significant difference in plasma insulin activity between before and after the administration.(III) No significant effect of BZ 55 was observed in vitro experiments on the basal uptake and insulin effect by the isolated rats diaphragm.

メゾ蓚酸鹽の持つている抗糖尿病作用の機序に關する實験成續は, 前報に報告した通りであい.正常家兎及びラツテに就てメゾ蓚酸カルシウムの毒性を檢べ, 併せて長期間連續藥物を投與した動物の各主要験器を組織學的に檢索した結果をこゝに報告する.

先に我々はAlloxan糖尿病家兎及び犬にメゾ蓚酸カルシウム又はナトリウムを經口投與して糖尿の減少又は消失, 高い空腹時血糖の低下, 血中アセトン體の減少, 及び尿中の非蛋白性窒素の排泄減少を來す事實, 又この際膵臓全摘出犬に對しては作用の無い事も合わせ報告した.この事實はAllonan糖尿病動物に對するメゾ蓚酸鹽の影響は膵臓自體の機能と密接な關係あるを思わしめるものである.こゝにこの藥物の作用機轉を追求する爲に行われた實験の一部を報告する.

This paper describes fabrication of silicon nitride radial turbine wheels 90 mm in diameter. The wheels were hot spin tested without failure at turbine tip speeds up to 600 m/s. The reliability of shrink fit of metal shaft and ceramic wheel was demonstrated in a turbocharger test. Results of the hot spin test are discussed in relation to the nature of defects and compared with the analytic prediction using Weibull statistics and finite element analysis.