APOE Alleles With Tau and Aβ Pathology In Patients With Amyotrophic Lateral Sclerosis and Parkinsonism-Dementia Complex in the Kii Peninsula

BACKGROUND AND OBJECTIVES

To examine the association of the apolipoprotein E gene (APOE) ε4 and ε2 alleles with the pathological features of patients with amyotrophic lateral sclerosis and Parkinsonism-dementia complex cases in the Kii peninsula of Japan (Kii ALS/PDC) METHODS: We analyzed APOE polymorphisms in 18 autopsy patients with ALS/PDC, consisting of nine, eight, and one patient with PDC, ALS, and PDC followed by ALS, respectively. Moreover, we revealed the relationship between APOE polymorphisms and Aβ and tau pathologies, respectively.

RESULTS

The frequency of the ε4 allele was not different between patients with Kii ALS/PDC and control participants. APOE ε4 was associated with increased Aβ pathology (p=0.005 by χ² test) but not with increased tau pathology (p=0.984). The frequency of the ε2 allele was apparently higher than that of control participants (p=0.254). APOE ε2 allele was associated with increased tau pathology (p=0.009) and not with reduced Aβ pathology (p=0.383) in patients with Kii ALS/PDC.

DISCUSSION

Although there was no overrepresentation of the frequency of the ε4 or ε2 allele, our findings suggest that the ε2 allele is associated with increased tau pathology and not with reduced Aβ pathology in patients with Kii ALS/PDC.

[Recurrent myelitis in a case of IgG4-related respiratory disease]

We report an 80-year-old man with IgG4-related pleuritis who had been treated with a low dose oral steroid for two years and developed recurrent myelitis. He was admitted to our hospital with gradually worsening numbness in the lower body and difficulty in walking due to mild weakness and loss of proprioception in the legs. T₂-weighted MR images of the spinal cord showed a high signal intensity lesion, located centrally in the spinal cord at the Th2-4 spine levels. Laboratory data revealed an elevated serum IgG4 level and cerebrospinal fluid protein level. Anti-aquaporin 4 antibody, anti-myelin oligodendrocyte glycoprotein antibody and other autoantibodies were negative. He showed a good response to the administration of steroid pulse therapy with almost resolution of the neurological symptoms and MRI findings. He was followed with the maintenance therapy with a low dose oral steroid. After one year, he developed recurrence of myelitis in the lower end of the medulla oblongata and in the central to dorsal area at the C2 spine level. Each lesion of recurrent myelitis was located within 3 vertebral segments length and improved without focal spinal atrophy. Recently, IgG4-related disease (IgG4-RD)-associated inflammation involving brain parenchyma and spinal cord were reported. Further investigations are needed to elucidate the relationship between IgG4-RD and seronegative recurrent myelitis.

An immigrant family with Kii amyotrophic lateral sclerosis/parkinsonism-dementia complex

OBJECTIVES

Amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) is a unique endemic on Guam island of the USA, the Kii Peninsula of Japan, and Papua state of Indonesia. The pathomechanism of ALS/PDC remains to be solved, although interaction between some environmental factors and genetic background is plausible. This is the first autopsy-proven immigrant family of ALS/PDC of the Kii Peninsula.

METHODS

A daughter and her father immigrated to the high incident area from outside the Kii Peninsula. The father developed ALS 18 years later after immigration, and his daughter also developed ALS 65 years after immigration. They showed pure ALS phenotype without parkinsonism and dementia.

RESULTS

The daughter was diagnosed neuropathologically with Kii ALS/PDC with multiple proteinopathies: tauopathy, α-synucleinopathy, and TDP-43 proteinopathy. Gene analysis of familial ALS-related genes, including C9orf72, showed no mutation.

DISCUSSION

The findings in an immigrant family established that certain environmental factors play a critical role in the pathogenesis of Kii ALS/PDC.

"Endemic paraplegia of Koza in Kii" in Honcho Koji Innen Shu published in 1689 is probably the earliest description of amyotrophic lateral sclerosis of Kii Peninsula: Presentation of the original and investigation of factuality

High prevalence of amyotrophic lateral sclerosis (ALS) in Kii Province (Kii) located in southern Kii Peninsula was first pointed out by Kinnosuke Miura in 1911, and epidemiological studies by Kiyoshi Kimura et al. verified extremely high incidence after World War II. In 1970s, Yoshiro Yase pointed out that "endemic paraplegia of Koza in Kii" in Honcho Koji Innen Shu published in 1689 would mean the same disorder as that of ALS and be the earliest description of Kii ALS although he gave no clear grounds. In this study, the original of the article was presented with an English translation, and factuality of it was investigated from the viewpoints of geography, geology, culture and history of Kii. As a result, it was shown that the article was probably written based on historical events and that the "endemic paraplegia" meant the same disorder as Kii ALS. The author has concluded that "endemic paraplegia of Koza in Kii" is likely to be the earliest description of Kii ALS since ALS is included in the causes of paraplegias of these kinds.

Expression of Mutant Ubiquitin and Proteostasis Impairment in Kii Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex Brains

Kii amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) is a progressive neurodegenerative disorder that is endemic to the Kii peninsula of Japan. The disorder is clinically characterized by a variable combination of parkinsonism, dementia, and motor neuron symptoms. Despite extensive investigations, the etiology and pathogenesis of ALS/PDC remain unclear. At the neuropathological level, Kii ALS/PDC is characterized by neuronal loss and tau-dominant polyproteinopathy. Here, we report the accumulation of several proteins involved in protein homeostasis pathways, that is, the ubiquitin-proteasome system and the autophagy-lysosome pathway, in postmortem brain tissue from a number of Kii ALS/PDC cases (n = 4). Of particular interest is the presence of a mutant ubiquitin protein (UBB+1), which is indicative of disrupted ubiquitin homeostasis. The findings suggest that abnormal protein aggregation is linked to impaired protein homeostasis pathways in Kii ALS/PDC.

[Lessons from the 116 years (1902-2018) of history of the Japanese Society of Neurology in establishing its identity]

The Japanese Society of Neurology and Psychiatry was founded in 1902 as a joint society of Neurology and Psychiatry, but was renamed the Japanese Society of Psychiatry and Neurology in 1935 because of the stagnation of activities of Neurology and the rise of those of Psychiatry. After World War II, activities of Neurology were restored and the Japanese Society of Neurology (JSN) independent from the Societies of Internal Medicine and Psychiatry was established in 1960 after overcoming many difficulties. In 1975, neurology was approved by law as one of the specialized fields of medicine. After that, neurology and JSN developed dramatically, both in research and medical practices. As of 2018, JSN had 9,000 members and more than 5,500 board-certified neurology specialists. JSN successfully hosted the World Congress of Neurology twice in 1981 and 2017. In 2002, JSN accepted the offer to join the Japanese Board of Medical Specialties as one of the subspecialties of Internal Medicine. In 2018 JSN enacted a new policy to upgrade the neurology specialist from a subspecialty of Internal Medicine to an independent major medical field. Lessons of the 116 years of history of the Society would teach us a sensible way to achieve the goals.

Ultra-high-dose methylcobalamin in amyotrophic lateral sclerosis: a long-term phase II/III randomised controlled study

OBJECTIVE

To evaluate the efficacy and safety of intramuscular ultra-high-dose methylcobalamin in patients with amyotrophic lateral sclerosis (ALS).

METHODS

373 patients with ALS (El Escorial definite or probable; laboratory-supported probable; duration ≤36 months) were randomly assigned to placebo, 25 mg or 50 mg of methylcobalamin groups. The primary endpoints were the time interval to primary events (death or full ventilation support) and changes in the Revised ALS Functional Rating Scale (ALSFRS-R) score from baseline to week 182. Efficacy was also evaluated using post-hoc analyses in patients diagnosed early (entered ≤12 months after symptom onset).

RESULTS

No significant differences were detected in either primary endpoint (minimal p value=0.087). However, post-hoc analyses of methylcobalamin-treated patients diagnosed and entered early (≤12 months' duration) showed longer time intervals to the primary event (p<0.025) and less decreases in the ALSFRS-R score (p<0.025) than the placebo group. The incidence of treatment-related adverse events was similar and low in all groups.

CONCLUSION

Although ultra-high-dose methylcobalamin did not show significant efficacy in the whole cohort, this treatment may prolong survival and retard symptomatic progression without major side effects if started early.

TRIAL REGISTRATION NUMBER

NCT00444613.

Self-Supporting Hybrid Supercapacitor Electrodes Based on Carbon Nanotube and Activated Carbons

Self-supporting AC (activated carbon)-FWCNT (few-wall carbon nanotubes) hybrid electrodes were fabricated by mixing of ACs with high specific surface area (SSA) and sub-millimeter-long FWCNTs. In order to fabricate the hybrid electrodes, AC and FWCNT were mixed in a weight ratio of 9:1, dispersed by bath-sonication and vacuum-filtrated on a membrane filter. The addition of FWCNTs gives conductivity and mechanical strength, and replace metallic current collectors in thick (0.1 mm) electrodes. For making an electrode, three different ACs that derived from walnut shell (WS), that from apricot stones (AS), and that commercially used for capacitors (YP-80F, Kuraray Chemical Co., Osaka Japan), were used with FWCNT in weight ratio of AC:FWCNT = 9:1. An electrode based only on FWCNT was also prepared as a reference for comparison. Electrochemical properties of the obtained electrodes were investigated by the cyclic voltammetry method (CV). Electrochemical characteristics were measured using the three-electrode cell contained of YP80F-FWCNT, AS-FWCNT, WS-FWCNT as a working electrode, a YP-80F-FWCNT counter electrode and a Ag/AgCl reference electrode with an electrolyte of 1 M Na2SO4 aqueous solution. Also, the morphological properties of obtained electrodes were studied using scanning electron microscope (SEM), the SSA was investigated by the Brunauer-Emmett-Teller analysis. SSA, conductivity, and resistivity of AS-FWCNT and WS-FWCNT electrodes were summarized. Both the AS-FWCNT and WS-FWCNT hybrid electrodes showed specific capacitances of about 140 F/g at 1 mV/s and about 100 F/g at 100 mV/s, which are similar or even better than the AC-CNT hybrid electrode made of commercialized AC (YP-80F).

Nitrative Stress and Tau Accumulation in Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex (ALS/PDC) in the Kii Peninsula, Japan

Objective: The Kii Peninsula of Japan is known to be a high incidence area of amyotrophic lateral sclerosis/parkinsonism-dementia complex (Kii ALS/PDC) with tauopathy. Nitrative stress and oxidative stress on ALS/PDC and their relationship to tau pathology were clarified.

Methods: Seven patients with Kii ALS/PDC (3 males and 4 females, average age 70.7 years, 3 with ALS, 2 with ALS with dementia, and 2 with PDC) were analyzed in this study. Five patients with Alzheimer's disease and five normal aged subjects were used as controls. Immunohistochemical analysis was performed on formalin-fixed, paraffin-embedded temporal lobe sections (the hippocampal area including hippocampus, prosubiculum, subiculum, presubiculum, and parahippocampal gyri) using antibodies to detect phosphorylated tau (anti-AT-8), nitrated guanine (anti-8-NG), anti-iNOS, anti-NFκB, and oxidized guanine (anti-8-OHdG) antibodies.

Results: Most hippocampal neurons of Kii ALS/PDC patients were stained with anti-8-NG, anti-iNOS, anti-NFκB, and anti-8-OHdG antibodies and some AT-8 positive neurons were co-stained with anti-8-NG antibody. The numbers of 8-NG positive neurons and 8-OHdG positive neurons were greater than AT-8 positive neurons and the number of 8-NG positive neurons was larger in patients with Kii ALS/PDC than in controls.

Conclusion: Nitrative and oxidative stress may take priority over tau accumulation and lead to the neurodegeneration in Kii ALS/PDC.

Amyotrophic lateral sclerosis and parkinsonism-dementia complex of the Hohara focus of the Kii Peninsula: A multiple proteinopathy?

The high incidence of amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex (PDC) has been previously known in the Kii Peninsula of Japan and in Guam. Recently, the accumulation of various proteins, such as tau, trans-activation response DNA binding protein 43 kDa (TDP-43), and alpha-synuclein (αSyn), was reported in the brains of patients with ALS/PDC in Guam. To confirm whether similar findings are present in Kii ALS/PDC, we neuropathologically examined the brains and spinal cords of 18 patients with ALS/PDC (clinical diagnoses: eight ALS and 10 PDC) in Hohara Village, which is the eastern focus of Kii ALS. The average age at death was 71.6 years, and 16 patients (88.9%) had a family history of ALS/PDC. Autopsy specimens were immunohistochemically examined with antibodies against four major proteins. Neurofibrillary tangles, including ghost tangles, and tau-positive astrocytes were distributed widely in all of the brains examined, and TDP-43-positive neuronal cytoplasmic inclusions were observed mainly in the limbic system. Synuclein pathology was present in 14 patients (77.8%). These patients were classified into three pathological subtypes according to the most prominent proteinopathy: the tauopathy-dominant type, the TDP-43 proteinopathy-dominant type, and the synucleinopathy-dominant type. Five patients with severe tau deposition showed clinical features of atypical parkinsonism and dementia with or without motor neuron disease. Eight patients were predominated by phosphorylated TDP-43 inclusions and clinically showed ALS, and five patients were predominated by synuclein pathology and clinically showed signs of PDC. Based on the common characteristic tau pathology, three subtypes seemed to be pathologically continuous on a spectrum of a single disease. Thus, we conclude that ALS/PDC in the Hohara focus of the Kii Peninsula is a single disease characterized neuropathologically by a multiple proteinopathy, even though the clinical manifestations of the three subtypes differed from each other. It remains unclear whether the coexistence of the three proteinopathies was incidental or pathogenetically related.

A migration case of Kii amyotrophic lateral sclerosis/parkinsonism dementia complex with the shortest stay in the endemic area and the longest incubation to develop the disease

Amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC) is an endemic disease observed in the Kii peninsula, Guam, and Papua. We report a case of a 76-year old man with ALS/PDC of the Kii peninsula of Japan (Kii ALS/PDC). The patient was born and grew up in the Kii peninsula. He moved out at age three, and developed symptoms 73years later. He showed pyramidal sign, parkinsonian symptoms, and mildly impaired cognitive function. ¹³¹I-metaiodobenzylguanidine myocardial scintigraphy showed decreased cardiac sympathetic nerve function, and dopamine transporter single photon emission computed tomography imaging showed decreased ¹²³I-N-ω-fluoropropyl-2β-carbomethoxy3β-(4-iodophenyl) nortropane accumulation. Cerebral blood flow showed hypoperfusion. Positron emission tomography showed widespread tau deposition in his brain. This is a migration case of Kii ALS/PDC with the shortest stay in the endemic area and the longest delay to develop the disease, indicating a genetic factor for the disease development in a considerable degree.

Neutron activation analysis of scalp hair from ALS patients and residents in the Kii Peninsula, Japan

The aim of this study was to evaluate the accumulation of transition metals in the scalp hair of amyotrophic lateral sclerosis (ALS) patients in the Koza/Kozagawa/Kushimoto (K) area (K-ALS) in the Kii Peninsula, Japan. Metal contents were measured in the unpermed, undyed hair samples of 88 K-residents, 20 controls, 7 K-ALS patients, and 10 sporadic ALS patients using neutron activation analysis at the Research Reactor Institute, Kyoto University. A human hair standard and elemental standards were used as comparative standards. The contents of Zn, Mn, and V were higher, while that of S was lower in K-ALS patients than in the controls. The content of Mn in K-ALS patients negatively correlated with clinical durations. The content of Al was significantly higher in K-residents than in the controls, with 15.9 % of K-residents having high Mn contents over the 75th percentile of the controls. The contents of Zn, Mn, and V were high in the scalp hair of K-ALS patients and correlated with the content of Al. The accumulation of these transition metals may chronically increase metal-induced oxidative stress, which may, in turn, trigger the neuronal degeneration associated with K-ALS.

[Robert Wartenberg: the neurologist, the teacher, and the man]

Wartenberg was born in 1887 in Grodno, old Lithuania (present-day Belarus). He received his medical degree from the University of Rostock in 1919, and worked at the University of Freiburg until 1935, when he immigrated to the United States to escape Nazi Germany. He then worked at the University of California, San Francisco, and was appointed Clinical Professor of Neurology in 1952. He died of a heart illness in 1956. Wartenberg wrote more than 150 papers on clinical neurology in German and English, especially on reflexes and signs. His books, "Examination of Reflex" and "Diagnostic Tests in Neurology" were translated into many languages, including Japanese. His contribution to the study of reflexes includes Wartenberg's reflex of the thumb, head dropping test in Parkinson's disease, necessity of differentiating abdominal muscle and abdominal skin muscle reflexes, and many others. He had knowledge, skill, art and ability enough to translate difficult problems into tangible methods of diagnosis and treatment. He tried to diagnose and treat patients quickly, with minimum laboratory tests, and avoided invasive tests and expense of time and money. His efforts to provide patients with the best treatment in terms of time, safety, and cost, is the essence of medicine and is still worth practicing in modern neurology using advanced technology.

Neuropsychological study of amyotrophic lateral sclerosis and parkinsonism-dementia complex in Kii peninsula, Japan

BACKGROUND

The Kii peninsula of Japan is one of the foci of amyotrophic lateral sclerosis and parkinsonism-dementia complex (ALS/PDC) in the world. The purpose of this study is to clarify the neuropsychological features of the patients with ALS/PDC of the Kii peninsula (Kii ALS/PDC).

METHODS

The medical interview was done on 13 patients with Kii ALS/PDC, 12 patients with Alzheimer's disease, 10 patients with progressive supranuclear palsy, 10 patients with frontotemporal lobar degeneration and 10 patients with dementia with Lewy bodies. These patients and their carer/spouse were asked to report any history of abulia-apathy, hallucination, personality change and other variety of symptoms. Patients also underwent brain magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), and neuropsychological tests comprising the Mini Mental State Examination, Raven's Colored Progressive Matrices, verbal fluency, and Paired-Associate Word Learning Test and some of them were assessed with the Frontal Assessment Battery (FAB).

RESULTS

All patients with Kii ALS/PDC had cognitive dysfunction including abulia-apathy, bradyphrenia, hallucination, decrease of extraversion, disorientation, and delayed reaction time. Brain MRI showed atrophy of the frontal and/or temporal lobes, and SPECT revealed a decrease in cerebral blood flow of the frontal and/or temporal lobes in all patients with Kii ALS/PDC. Disorientation, difficulty in word recall, delayed reaction time, and low FAB score were recognized in Kii ALS/PDC patients with cognitive dysfunction.

CONCLUSIONS

The core neuropsychological features of the patients with Kii ALS/PDC were characterized by marked abulia-apathy, bradyphrenia, and hallucination.

Amyotrophic lateral sclerosis and parkinsonism in Papua, Indonesia: 2001-2012 survey results

OBJECTIVE

Only one previous follow-up study of amyotrophic lateral sclerosis (ALS) and parkinsonism in Papua, Indonesia has been carried out since a survey undertaken in 1962-1981 by Gajdusek and colleagues. Therefore, to clarify the clinical epidemiology of ALS and parkinsonism in the southern coastal region of Papua, the clinical characteristics and prevalence of the diseases in this region were examined and assessed.

METHODS

Cases of ALS and parkinsonism were clinically examined during a 2001-2012 survey in Bade and other villages along the Ia, Edera, Dumut and Obaa rivers in Papua, Indonesia. Possible, probable and definite ALS was diagnosed clinically by certified neurologists based on El Escorial criteria. The criteria for a diagnosis of parkinsonism were the presence of at least two of the four following signs: tremor, rigidity, bradykinesia and postural impairment with a progressive course.

RESULTS

During the survey, 46 cases of ALS and/or parkinsonism were diagnosed within a population range of 7000 (2001-2002) to 13 900 (2007-2012). The 46 cases consisted of 17 probable-definite cases of ALS, including three with cognitive impairment (CI), 13 cases of overlapping possible, probable or definite ALS and parkinsonism, including five with CI, and 16 cases of parkinsonism, including one with CI. The crude point prevalence rate of pure ALS was estimated to be at least 73 (95% CI 0 to 156) to 133 (27 to 240)/100 000 people and that of overlapping ALS and parkinsonism at least 53 (0 to 126) to 98 (2 to 193)/100 000 in 2007, or 2010 in some regions.

CONCLUSIONS

While the prevalence of ALS in Papua has decreased over the past ∼30-35 years, it remains higher than the global average. There was a high prevalence of overlapping ALS, parkinsonism and CI, which has also been previously reported in Guam and Kii.

EIF4G1 gene mutations are not a common cause of Parkinson's disease in the Japanese population

Pathogenic mutations in the EIF4G1 gene were recently reported as a cause of autosomal dominant parkinsonism. To assess the frequency of EIF4G1 mutations in the Japanese population we sequenced the entire gene coding region (31 exons) in 95 patients with an apparent autosomal dominant inherited form of Parkinson's disease. We detected three novel point mutations located in a poly-glutamic acid repeat within exon 10. These variants were screened through 224 Parkinson's disease cases and 374 normal controls from the Japanese population. We detected the poly-glutamic acid deletion in exon 10 in two additional patients with sporadic Parkinson's disease. Although the EIF4G1 variants identified in the present study were not observed in control subjects, co-segregation analyses and population-based screening data suggest they are not pathogenic. In conclusion, we did not identify novel or previously reported pathogenic mutations (including the p.A502V and p.R1205H mutants) within EIF4G1 in the Japanese population, thus future studies are warranted to elucidate the role of this gene in Parkinson's disease.

Clinical features and a mutation with late onset of limb girdle muscular dystrophy 2B

OBJECTIVE AND METHODS

Dysferlin encoded by DYSF deficiency leads to two main phenotypes, limb girdle muscular dystrophy (LGMD) 2B and Miyoshi myopathy. To reveal in detail the mutational and clinical features of LGMD2B in Japan, we observed 40 Japanese patients in 36 families with LGMD2B in whom dysferlin mutations were confirmed.

RESULTS AND CONCLUSIONS

Three mutations (c.1566C>G, c.2997G>T and c.4497delT) were relatively more prevalent. The c.2997G>T mutation was associated with late onset, proximal dominant forms of dysferlinopathy, a high probability that muscle weakness started in an upper limb and lower serum creatine kinase (CK) levels. The clinical features of LGMD2B are as follows: (1) onset in the late teens or early adulthood, except patients homozygous for the c.2997G>T mutation; (2) lower limb weakness at onset; (3) distal change of lower limbs on muscle CT at an early stage; (4) impairment of lumbar erector spinal muscles on muscle CT at an early stage; (5) predominant involvement of proximal upper limbs; (6) preservation of function of the hands at late stage; (7) preservation of strength in neck muscles at late stage; (8) lack of facial weakness or dysphagia; (9) avoidance of scoliosis; (10) hyper-Ckaemia; (11) preservation of cardiac function; and (12) a tendency for respiratory function to decline with disease duration. It is important that the late onset phenotype is found with prevalent mutations.

Environmental characteristics and oxidative stress of inhabitants and patients with amyotrophic lateral sclerosis in a high-incidence area on the Kii Peninsula, Japan

OBJECTIVE

Although Oshima, in the Kii Peninsula of Japan, is located within a high incidence area of amyotrophic lateral sclerosis (ALS) (Koza/Kozagawa/Kushimoto area, K area), no patients with ALS were detected between 1960 and 1999. However, the incidence recently increased between 2000 and 2009. On Oshima, the source of drinking water was changed from a regional river/wells to the Kozagawa River in the K area in 1975. We speculate that this change in water source may have played a role in the recent increase in the incidence of ALS. The aim of this study is to find contributing factors that may have triggered the locally high incidence of ALS.

METHODS

We investigated a possible association between the mineral content of drinking water and serum and oxidative stress markers among patients with ALS in the K area (K-ALS), residents of Oshima and controls.

RESULTS

We found that the levels of Ca and Zn in the recent drinking water in Oshima are low and that the serum levels of Ca and Zn in the Oshima residents and patients with K-ALS were significantly lower, while the oxidative stress markers were significantly higher, than those of the controls. The serum Zn and urinary 8-OHdG/creatinine levels explained 60% and 58% of the variations among the three groups, respectively. The serum Zn levels were negatively correlated with the serum Cu levels in the patients with K-ALS, and the serum Cu levels exhibited a tendency to be positively correlated with the 8-OHdG/creatinine levels in both the patients with K-ALS (r: 0.64) and the residents free from K-ALS (r: 0.32, p<0.01).

CONCLUSION

Taken together, we suggest that the low levels of Ca and Zn in the drinking water are possibly associated with an imbalance of metal metabolism in Oshima residents and an increase in oxidative stress markers in patients with K-ALS, although the causative relationship is not clear. This is a cross-sectional study, and a prospective study is needed in the future.

C9ORF72 repeat expansion in amyotrophic lateral sclerosis in the Kii peninsula of Japan

BACKGROUND

In the Kii peninsula of Japan, high prevalences of amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex have been reported. There are 2 major foci with a high prevalence, which include the southernmost region neighboring the Koza River (Kozagawa and Kushimoto towns in Wakayama prefecture) and the Hohara district (Mie prefecture).

OBJECTIVE

To delineate the molecular basis of ALS in the Kii peninsula of Japan, we analyzed hexanucleotide repeat expansion in the chromosome 9 open reading frame 72 (C9ORF72) gene, which has recently been identified as a frequent cause of ALS and frontotemporal dementia in the white population.

DESIGN

Case series.

SETTING

University hospitals.

PATIENTS

Twenty-one patients (1 familial patient and 20 sporadic patients) with ALS from Wakayama prefecture, and 16 patients with ALS and 16 patients with parkinsonism-dementia complex originating from Mie prefecture surveyed in 1994 through 2011 were enrolled in the study. In addition, 40 probands with familial ALS and 217 sporadic patients with ALS recruited from other areas of Japan were also enrolled in this study.

MAIN OUTCOME MEASURES

After screening by repeat-primed polymerase chain reaction, Southern blot hybridization analysis was performed to confirm the expanded alleles.

RESULTS

We identified 3 patients with ALS (20%) with the repeat expansion in 1 of the 2 disease foci. The proportion is significantly higher than those in other regions in Japan. Detailed haplotype analyses revealed an extended shared haplotype in the 3 patients with ALS, suggesting a founder effect.

CONCLUSIONS

Our findings indicate that the repeat expansion partly accounts for the high prevalence of ALS in the Kii peninsula.

An increase in ALS incidence on the Kii Peninsula, 1960-2009: a possible link to change in drinking water source

We investigated changes in the incidence of amyotrophic lateral sclerosis (ALS) in the Koza/Kozagawa/Kushimoto area (K. area) in the Kii Peninsula, Japan in 1960–2009. Probable and definite ALS cases diagnosed using El Escorial criteria were collected during a five-decade period: period I-V, 1960–2009. Forty-three ALS patients matched the selection criteria in the overall K. area, including three patients on Oshima, a small island opposite the mainland K. area. The age- and gender-adjusted incidence of ALS in the overall K. area (standardized for the 2005 Japanese population) decreased from 5.47/100,000 (95% CI 1.86–9.08) in period I to 0.61/100,000 (95% CI-0.28–1.50) in period III, and then increased to 4.39/100,000 (95% CI 1.70–7.07) in periodV. On Oshima, the age- and gender-adjusted incidence of ALS was 9.45/100,000 (95% CI—7.39–26.29) in period V. The present research indicates an increase of ALS incidence in the K. area, especially on Oshima. A limitation of this study was the small population.

Clinical, pathologic and genetic studies on autosomal recessive early-onset parkinsonism with diurnal fluctuation

To clarify the genetic mode and clinical characteristics of familial early-onset parkinsonism with diurnal fluctuation, we studied 43 patients from 22 families. The estimated segregation ratio (0.2963) and absence of gender preponderance indicated autosomal recessive inheritance. Clinical features included the average age at onset of 26.1 years, parkinsonism with marked diurnal fluctuation, remarkable effect of levodopa, dyskinesias, dystonia, hyperreflexia, absence of dementia, and a benign course; autonomic symptoms were only mild if present. Autopsy study in one of our patients disclosed neuronal loss without Lewy bodies and the presence of melanin-poor neurons in the substantia nigra. Linkage analysis on 16 families mapped the disease gene to chromosome 6q25.2-27.

VPS35 mutation in Japanese patients with typical Parkinson's disease

Vacuolar protein sorting 35 (VPS35) was recently reported to be a pathogenic gene for late-onset autosomal dominant Parkinson's disease (PD), using exome sequencing. To date, VPS35 mutations have been detected only in whites with PD. The aim of the present study was to determine the incidence and clinical features of Asian PD patients with VPS35 mutations. We screened 7 reported nonsynonymous missense variants of VPS35, including p.D620N, known as potentially disease-associated variants of PD, in 300 Japanese index patients with autosomal dominant PD and 433 patients with sporadic PD (SPD) by direct sequencing or high-resolution melting (HRM) analysis. In addition, we screened 579 controls for the p.D620N mutation by HRM analysis. The p.D620N mutation was detected in 3 patients with autosomal dominant PD (1.0%), in 1 patient with SPD (0.23%), and in no controls. None of the other reported variants of VPS35 were detected. Haplotype analysis suggested at least 3 independent founders for Japanese patients with p.D620N mutation. Patients with the VPS35 mutation showed typical tremor-predominant PD. We report Asian PD patients with the VPS35 mutation. Although VPS35 mutations are uncommon in PD, the frequency of such mutation is relatively higher in Japanese than reported in other populations. In VPS35, p.D620N substitution may be a mutational hot spot across different ethnic populations. Based on the clinical features, VPS35 should be analyzed in patients with PD, especially autosomal dominant PD or tremor-predominant PD.

ALS-parkinsonism-dementia complex of Kii and other related diseases in Japan

The ALS/parkinsonism-dementia complex (PDC) of Kii is an endemic disease with a diverse phenotypic expression characteristic of classical ALS, parkinsonism and dementia. Its clinical and neuropathological manifestations are similar to a syndrome found in Guam, sharing classical ALS pathology together with many neurofibrillary tangles in the brain. The incidence rates of ALS declined dramatically between the 1950s and 1980s. In the 1990 s, Kuzuhara found a high incidence of PDC with abundant neurofibrillary tangles, similar to Guamanian PDC. The incidence rates of PDC dramatically rose during the 1980s and 1990 s, and PDC replaced ALS. More than 70% of patients in the endemic region had a family history of ALS or PDC. We recently found a new gene OPTN causing ALS, and have extended its clinical survey in Japan. Two autopsied cases showed involvement of basal ganglia and/or cerebral cortex with neurofibrillary tangles. A few family members also showed dementia and parkinsonism without evidence of motor neuron disease. Moreover the penetrance seems to be incomplete. Despite these similarities, OPTN mutations were not found in the Kii patients. We speculate that the Kii/ALS-PDC could primarily be a genetic disease, and its clinical manifestation is modified by other genes or environmental factors.

Analyses of the MAPT, PGRN, and C9orf72 mutations in Japanese patients with FTLD, PSP, and CBS

BACKGROUND

Mutations in the microtubule associated protein tau (MAPT) and progranulin (PGRN) have been identified in several neurodegenerative disorders, such as frontotemporal lobar degeneration (FTLD), progressive supranuclear palsy (PSP), and corticobasal syndrome (CBS). Recently, C9orf72 repeat expansion was reported to cause FTLD and amyotrophic lateral sclerosis (ALS). To date, no comprehensive analyses of mutations in these three genes have been performed in Asian populations. The aim of this study was to investigate the genetic and clinical features of Japanese patients with MAPT, PGRN, or C9orf72 mutations.

METHODS

MAPT and PGRN were analyzed by direct sequencing and gene dosage assays, and C9orf72 repeat expansion was analyzed by repeat-primed PCR in 75 (48 familial, 27 sporadic) Japanese patients with FTLD, PSP, or CBS.

RESULTS

We found four MAPT mutations in six families, one novel PGRN deletion/insertion, and no repeat expansion in C9orf72. Intriguingly, we identified a de novo MAPT p.S285R mutation. All six patients with early-onset PSP and the abnormal eye movements that are not typical of sporadic PSP had MAPT mutations. The gene dosages of MAPT and PGRN were normal.

DISCUSSION

MAPT p.S285R is the first reported de novo mutation in a sporadic adult-onset patient. MAPT mutation analysis is recommended in both familial and sporadic patients, especially in early-onset PSP patients with these abnormal eye movements. Although PGRN and C9orf72 mutations were rare in this study, the PGRN mutation was found in this Asian FTLD. These genes should be studied further to improve the clinicogenetic diagnoses of FTLD, PSP, and CBS.

[Muro disease: amyotrophic lateral sclerosis/parkinsonism-dementia complex in Kii peninsula of Japan]

Muro disease refers to the endemic amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex (PDC) in the high incidence ALS focus in the Muro district of the Kii peninsula. Kii paralysis was first described in the 1680s in a folk literature, and as ALS in the medical literature by Kin-no-suke Miura in 1911. Two high-incidence ALS foci were discovered in 1960s by Kimura and Yase, and retro- and anterospective epidemiological surveys were started. Kii ALS was neuropathologically characterized by classical ALS pathology together with many neurofibrillary tangles (NFTs) in the brain, similar to Guamanian ALS. The incidence rates of ALS dramatically declined during the 1950s and 1980s, resulting in the disappearance of the high-incidence foci. In the early 1990s, however, Kuzuhara found existence of high-incidence of ALS in the region, and, in addition, of a high-incidence of PDC with abundant NFTs, similar to Guamanian PDC. The incidence rates of PDC dramatically rose during the 1980s and 1990s, and PDC replaced ALS. Unsuccessful attempts were made to identify cause and pathogenesis of the disease in minerals and environmental factors. More than 70% of patients in the endemic region had a family history of ALS or PDC; therefore, genetic factors were suspected as the cause. The authors analyzed the causative and risk candidate genes in the affected and unaffected family members, but failed to find genes related to ALS/PDC. The changing pattern of Muro disease from ALS with a younger onset and rapid progression to PDC with a later onset and longer survival suggests that some unknown environmental factor(s) might modulate the disease process, which basically might be programmed in the gene(s).

No evidence for pathogenic role of GIGYF2 mutation in Parkinson disease in Japanese patients

Grb10-Interacting GYF Protein-2 (GIGYF2) is a candidate gene for PARK11 locus. To date, seven different GIGYF2 missense mutations have been identified in patients with familial Parkinson disease (PD) of European descent. To clarify the pathogenic role of GIGYF2 in PD, we analyzed the frequency of GIGYF2 mutations in 389 Japanese patients with PD (including 93 patients with late-onset familial PD, 276 with sporadic PD, and 20 with a single heterozygous mutation in the PD-associated genes), and 336 Japanese normal controls, by direct sequencing and/or high-resolution melting analysis. None of the reported GIGYF2 mutations or digenic mutations were detected. Two novel non-synonymous variants were identified (p.Q1211delQ and p.H1023Q), however, we could not determine their roles in PD. In summary, we found no evidence for PD-associated roles of GIGYF2 mutations. Our data suggest that GIGYF2 is unlikely to play a major role in PD in Japanese patients, similar to other populations.

Prospective 10-year surveillance of human prion diseases in Japan

We analysed the epidemiological data and clinical features of patients with prion diseases that had been registered by the Creutzfeldt-Jakob Disease Surveillance Committee, Japan, over the past 10 years, since 1999. We obtained information on 1685 Japanese patients suspected as having prion diseases and judged that 1222 patients had prion diseases, consisting of definite (n=180, 14.7%) and probable (n=1029, 84.2%) cases, except for dura mater graft-associated Creutzfeldt-Jakob disease which also included possible cases (n=13, 1.1%). They were classified into 922 (75.5%) with sporadic Creutzfeldt-Jakob disease, 216 (17.7%) with genetic prion diseases, 81 (6.6%) with acquired prion diseases, including 80 cases of dura mater graft-associated Creutzfeldt-Jakob disease and one case of variant Creutzfeldt-Jakob disease, and three cases of unclassified Creutzfeldt-Jakob disease (0.2%). The annual incidence rate of prion disease ranged from 0.65 in 1999 to 1.10 in 2006, with an average of 0.85, similar to European countries. Although methionine homozygosity at codon 129 polymorphism of the prion protein gene was reported to be very common (93%) in the general Japanese population, sporadic Creutzfeldt-Jakob disease in Japan was significantly associated with codon 129 homozygosity (97.5%), as reported in western countries. In sporadic Creutzfeldt-Jakob disease, MM1 type (Parchi's classification) is the most common, as in western countries. Among atypical sporadic Creutzfeldt-Jakob disease cases, the MM2 type appeared most common, probably related to the very high proportion of methionine allele in the Japanese population. As for iatrogenic Creutzfeldt-Jakob disease, only dura mater graft-associated Creutzfeldt-Jakob disease cases were reported in Japan and, combined with the data from previous surveillance systems, the total number of dura mater graft-associated Creutzfeldt-Jakob disease was 138, comprising the majority of worldwide dura mater graft-associated Creutzfeldt-Jakob disease patients. Regarding genetic prion diseases, the most common mutation of prion protein gene was V180I (41.2%), followed by P102L (18.1%), E200K (17.1%) and M232R (15.3%), and this distribution was quite different from that in Europe. In particular, V180I and M232R were quite rare mutations worldwide. Patients with V180I or M232R mutations rarely had a family history of prion diseases, indicating that a genetic test for sporadic cases is necessary to distinguish these from sporadic Creutzfeldt-Jakob disease. In conclusion, our prospective 10-year surveillance revealed a frequent occurrence of dura mater graft-associated Creutzfeldt-Jakob disease, and unique phenotypes of sporadic Creutzfeldt-Jakob disease and genetic prion diseases related to the characteristic distribution of prion protein gene mutations and polymorphisms in Japan, compared with those in western countries.

[Treatment strategy of Alzheimer's disease: pause in clinical trials of Abeta vaccine and next steps]

The important pathognomonic features of Alzheimer disease (AD) brain are the occurrence of abundant neurofibrillary tangles (NFTs) in neurons and presence of extracellular deposits of beta-amyloid (Abeta)- senile plaques. In the early 1980s, the NFTs were characterized, and cerebral amyloid was purified; further the amino acid sequences of the tau protein in the NFTs and of Abeta were identified. Immunohistochemical studies with antibodies to tau and Abeta revealed that extracellular accumulation of Abeta precedes that of tau in neurons. Molecular genetic studies revealed that abnormal gene mutations of familial AD accelerate Abeta production. On the basis of these findings, the amyloid cascade hypothesis that Abeta accumulation is the primary cause of neuronal degeneration and induces accumulation of tau in the AD brain was proposed and widely accepted. Thus, on the basis of this hypothesis, transgenic AD mice were treated with Abeta vaccine; the Abeta amyloid plaques were eliminated, and a dramatic improvement of the behavioral deficits was observed in the treated mice. The great success of preclinical studies promoted clinical trials of the Abeta vaccine in AD patients. However,the clinical trials were discontinued because of the occurrence of severe meningoencephalitis. Postmortem examination of the brains of the vaccinated patients with high titer of the anti- Abeta antibody in the serum revealed elimination of the Abeta plaques along with presence of cerebral inflammation. However, in autopsy-proven cases, assessment of the clinical and cognitive functions of the patients did not provide any evidence for improved survival or prolongation of the time to severe dementia. Thus, anti-Abeta antibody could eliminate the accumulated Abeta but could not rescue the degenerated neurons. Thus, the AD treatment strategy should be converted from repair and cure of AD to prevention. Anti-Abeta therapy must be started at the preclinical stage, and it is necessary to focus on tau and other proteins, mitochondria, glial cells, and other factors that influence the degeneration of neurons.

Clinical features of non-hypertensive lobar intracerebral hemorrhage related to cerebral amyloid angiopathy

BACKGROUND AND PURPOSE

The present study aims to clarify the clinical features of non-hypertensive cerebral amyloid angiopathy-related lobar intracerebral hemorrhage (CAA-L-ICH).

METHODS

We investigated clinical, laboratory, and neuroimaging findings in 41 patients (30, women; 11, men) with pathologically supported CAA-L-ICH from 303 non-hypertensive Japanese patients aged >OR=55, identified via a nationwide survey as symptomatic CAA-L-ICH.

RESULTS

The mean age of patients at onset of CAA-L-ICH was 73.2 +/- 7.4 years; the number of patients increased with age. The corrected female-to-male ratio for the population was 2.2, with significant female predominance. At onset, 7.3% of patients received anti-platelet therapy. In brain imaging studies, the actual frequency of CAA-L-ICHs was higher in the frontal and parietal lobes; however, after correcting for the estimated cortical volume, the parietal lobe was found to be the most frequently affected. CAA-L-ICH recurred in 31.7% of patients during the average 35.3-month follow-up period. The mean interval between intracerebral hemorrhages (ICHs) was 11.3 months. The case fatality rate was 12.2% at 1 month and 19.5% at 12 months after initial ICH. In 97.1% of patients, neurosurgical procedures were performed without uncontrollable intraoperative or post-operative hemorrhage.

CONCLUSIONS

Our study revealed the clinical features of non-hypertensive CAA-L-ICH, including its parietal predilection, which will require further study with a larger number of patients with different ethnic backgrounds.

TRPM7 is not associated with amyotrophic lateral sclerosis-parkinsonism dementia complex in the Kii peninsula of Japan

Amyotrophic lateral sclerosis-parkinsonism dementia complex (ALS/PDC) is a distinct neurodegenerative disorder characterized by ALS pathology with neurofibrillary tangles (NFTs) in the spinal cord and brain. Recent clinical studies have revealed a high incidence and a high familial occurrence of ALS/PDC in both Guam and the Kii peninsula of Japan, suggesting a strong genetic predisposition to this disorder. The T1482I variant (rs8042919) of TRPM7 gene which is suggested to play roles in regulating the cellular homeostasis of Ca(2+), Mg(2+), and trace metals, has recently been reported to be associated with Guamanian patients with ALS/PDC. To investigate whether TRPM7 is associated with Kii ALS/PDC, we conducted parametric linkage analyses of the TRPM7 locus in a large extended family with ALS/PDC. Linkage analysis did not reveal any evidence supporting the linkage to the TRPM7 locus. Resequencing of the entire coding region of TRPM7 did not reveal any pathogenic mutations in an affected individual in this family. The allele frequencies of the T1482I in affected individuals in this family or in those from other families are not significantly different from those in regional controls or those in HapMap-JPT samples. These results indicate that TRPM7 is not associated with ALS/PDC in the Kii peninsula of Japan.

[Changes in the incidence and clinical features of ALS in the Koza, Kozagawa, and Kushimoto area of the Kii Peninsula--from the 1960s to the 2000s (follow-up study)]

In the 1960's, ALS was highly prevalent in the southern part of the Kii Peninsula, especially in the Koza, Kozagawa, and Kushimoto area (K area). Thereafter, the incidence of ALS was considered to have gradually decreased, and the disease almost disappeared in the 1980's. However, new patients have been continuously identified in this area, and indicating the importance of studying the changes in the incidences of ALS. This study investigated the characteristic clinical features and incidence of ALS in K area during the following periods: period I: between 1967 and 1971, period II: between 1989 and 1999, and period III: between 2000 and 2008. Data on all patients with motor neuron disease were collected for each year within these periods from medical doctors and medical staff of the regional public health center and municipal office. Neurologists on our research team examined and assessed each of these patients on the basis of the El Escorial criteria. Probable and definite ALS patients diagnosed by neurologists using the El Escorial criteria in K area during the research periods were collected. The crude incidence rate of ALS in K area were similar in period I, i.e. 6.0/100,000, and in period III, i.e., 5.7/100,000. The age-, and sex-adjusted incidence (considering the 2000 census) in women in K area during period III, especially in Kozagawa district, was higher than that in periods I and II. The adjusted incidence rate in Kozagawa district was 8.8/100,000, and was higher than that in other areas of the world. The clinical features of patients in this area were quite similar to those of patients with classical ALS. Five patients from 3 families with a family history of ALS and 2 patients without a family history presented with the clinical features of ALS and PDC during these research periods. The mean age at onset for period III was higher than that in period I (p < 0.01). The frequency of ALS patients with upper-extremity onset in period III was lower than that in period I (p = 0.05), whereas the frequency of patients with bulbar-onset has recently increased. Conclusion The result of present study indicate that the recent incidence of ALS in K area is high, the age of onset has recently become higher and the number of bulbar-onset patients has increased. All the abovementioned findings could be attributed to an increase in the senility rate in the population. Between 2000 and 2008, the age-adjusted incidence in ALS for women in K area, especially in the Kozagawa district, was high, indicating an increase in that the incidence of ALS among women in this area after 2000. The factors responsible for the high incidence of ALS in this area remain to be clarified.

[History of neurology and education on neurology in Japan]

The first medical society of Japanese neurologists and psychiatrists was founded in 1902, but psychiatrists gradually dominated in number. New "Japanese Society of Neurology" (JSN) was founded in 1960. The number of members was only 643 in 1960, while it rose up to 8,555 in 2009, including regular, junior, senior and associate members. JSN contributed much to solve the causes and treatment of the medicosocial and iatrogenic diseases such as Minamata disease and SMON (subacute myelopticoneuropathy) at its early period. In undergraduate education at medical school neurology is one of the core subjects in the curriculum, and almost all the 80 medical schools have at least one faculty neurologist. The Board of neurology of JSN was started in 1975, as the third earliest of the Japanese Medical Associations. It takes at least 6 years' clinical training after graduating from the medical school to take the neurology Board examinations. By 2009, 4,000 members passed the Board examinations. In 2002 JSN published evidence-based "Treatment Guidelines 2002" of 6 diseases: Parkinson's disease, stroke, chronic headache, dementia and ALS. As to the international issues, JSN hosted the 12th World Congress of Neurology in 1981, and international activities markedly increased after that. The first informal meeting with JSN and Korean Neurological Association (KNA) was held at the 48th JSN Annual Meeting in Nagoya in May 2007. In May 2008 the KNA-JSN 1st Joint symposium was held at the 49th Annual Meeting of JSN in Yokohama on "International comparison of neurological disorders: focusing on spinocerebellar atrophies (SCA) and epilepsies". In May 2009, KNA-JNS 2 nd Joint Symposium was held at the 50th JSN Annual Meeting in Sendai, inviting a speaker from Taiwan Neurological Society, on the subject "History and Education of Neurology in Japan, Korea and Taiwan". In this symposium, a strategy to make up the Northeast Asian Neurological Association was discussed.