Higher cognitive function in human brain is one of well-developed fields of neuroscience research in the 21^st century. Especially functional magnetic resonance imaging (fMRI) and near infrared recording system have brought so many non-clinical researchers whose background is such as cognitive psychology, economics, politics, pedagogy, and so on, to the human brain mapping study. Authors have introduced the ethical issues related to incidental findings during the fMRI recording for non-clinical purpose, which is a typical problem derived from such expanded human brain research under non clinical condition, that is, neuroethics. In the present article we would introduce neuroethical issues in contexts of "out of clinic" and "beyond academia".

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Patients with amyotrophic lateral sclerosis (ALS) must stand at crossroads when their disease advances causing respiratory failure; they have to decide whether or not to use tracheal intermittent positive pressure ventilation (TIPPV). Because the decision may devide their lives into alive or dead, appropriate information should be provided to the patients and their family before they make the decision. The information they would require include not only on medical care but also on social or economical issues if they should be on ventilator dependent life. In 2004 I had a research about the presenting the diagnosis of ALS. Words of patients and their family taught me that how poor the information we have given on presenting the diagnosis about ALS. In the United States, social workers assist patient decision making. In Japan, on the other hand, it has not been acknowledged that professions other than physicians should also be concerned in the patients making decision on medical treatments. Physician alone cannot deal with the needs of the patients and their family in the decision making. Not only physicians but also co-medical staff, for example, social workers, must take a part of the process of providing appropriate information.

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Medicine (medical care) is a study and technology backed by the high expertise human beings have created, passed down, and developed for human beings, to save sick people's lives and heal the pain and agony of illness. Because medicine is a specialized technology that is beyond the understanding of common people, medicine without expertise is not beneficial. Furthermore, medicine must essentially be evaluated in the actual field where people live. As long as medical science and medical care continue to be part of the social system, evaluation of medicine requires a social perspective. It is true that today, patients' rights are presented, ethics is pursued, and guidelines are provided. In reality, however, more than a few people are pushed into death without any "right of true self-determination" or "dignity." Particularly, in the field where "ethics of neurology" is required, the most difficult questions, including the decision to discontinue treatment, must be answered and conflicts can occur. The frightening thing is that words intentionally used from the political / economical aspect are penetrating into the general public without them realizing it. In these circumstances where expressions that can affect the content of treatment, such as "death with dignity" and "end-of-life (terminal), " are penetrating into society and being reflected in specific systems, while presenting a seemingly scientific, intellectual, ethical, and / or moral image, how should medical professionals handle the situation?

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Mutations in Cu/Zn superoxide dismutase (SOD1) have been linked to some familial cases of amyotrophic lateral sclerosis (ALS). In familial ALS kinders with mutations in the SOD1 gene, the age of onset of weakness varies greatly but the duration of illness appears to be characteristic to each mutation. For example, in patients with the L84V mutation, the average life expectancy is less than 1.5 year after the onset of symptoms, whereas patients harboring the H46R mutation have an average life expectancy of 18 years after the disease onset. In view of the evidence supporting the idea that familial ALS variants of SOD1 enzymes acquire toxic properties, the variations in the duration of illness in the different kinders might arise because each mutation imparts different degrees of toxicity to the mutant protein.
We developed rats that express a human SOD1 transgene with two different ALS-associated mutations (G93A and H46R) develop striking motor neuron degeneration and paralysis. The larger size of this rat model as compared with the ALS mice will facilitate studies involving manipulations of spinal fluid (implantation of intrathecal catheters for chronic therapeutic studies; CSF sampling) and spinal cord (e.g., direct administration of viral- and cell-mediated therapies).
Hepatocyte growth factor (HGF) is one of the most potent survival-promoting factors for motor neurons. To examine its both protective effect on motor neurons and therapeutic potential, we administered human recombinant HGF (hrHGF) by continuous intrathecal delivery to G93A transgenic (Tg) rats at onset of paralysis for 4 weeks. Intrathecal administration of hrHGF attenuates motor neuron degeneration and prolonged the duration of the disease by 63%. Our results indicated the therapeutic efficacy of continuous intrathecal administration of hrHGF in Tg rats. The results should prompt further clinical trials in ALS using continuous intrathecal administration of hrHGF.

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The mechanism underlying the characteristic selective motor neuron degeneration in amyotrophic lateral sclerosis (ALS) has remained elusive. Modest advances in this research field have been achieved by the identification of copper/zinc superoxide dismutase 1 (SOD1) as one of the causative genes for rare familial ALS and by the development and analysis of mutant SOD1 transgenic animal models. However, in sporadic ALS (SALS) with many more patients, causative or critical genes situated upstream of the disease pathway have not yet been elucidated and no available disease models have been established. We have been working on screening these genes employing and combining several new technologies such as cDNA microarray, molecular indexing, and laser capture microdissection. Many of the resultant genes are of intense interest and may provide a powerful tool for determining the molecular mechanisms of SALS. Of these, in this paper, we will focus on Dorfin, a RING finger-type E3 ubiquitin ligase and dynactin1, a major component of dynein/dynactin complex that is important for retrograde axonal transport. We are now challenging creation of the disease models by simulating the gene expression changes specifically observed in SALS patients.

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Because the whole of the management of ALS is palliative care, in this paper I presented about the management of each symptom, respiratory care, decision making of the mechanical ventilation, and the end of life care in Japan. We must be aware that the patients with ALS can continue to live if they decide to wear the tracheostomy ventilation (TV) even just before death, it is completely different form situation in cancer patients. In Japan about 20% of ALS patients choose TV, this figure is much higher than western countries. On the other hand, only 14% of neurologist have experience of opioids usage for ALS in 2007, much lower than western countries. We started to use opioids for ALS patients in 2005. We use morphine 10-30mg/day as maintenance dose in early phase without sever side effect. Eighty-eight percent patients reported relief of breathlessness, in 4 patients out of 9, PCO2 was decreased. It is big problem that the health insurance does not cover the cost of opioids for ALS. I want to emphasize that the best effort should be taken to relieve suffering not only for cancer patient but for every patient.

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[in Japanese]

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The histological hallmark of Parkinson's disease (PD) is the presence of fibrillar aggregates called Lewy bodies (LBs). LB formation has been considered to be a marker for neuronal degeneration, because neuronal loss is found in the predilection sites for LBs. To date, more than 70 molecules have been identified in LBs, in which α-synuclein is a major constituent of LB fibrils. α-Synuclein immunohistochemistry reveals that diffuse cytoplasmic staining develops into pale bodies via compaction, and that LBs arise from the peripheral portion of pale bodies. Abnormal accumulation of α-synuclein (diffuse cytoplasmic staining, pale bodies and LBs) is found in 10% of pigmented neurons in the substantia nigra and more than 50% of those in the locus ceruleus in PD. Recent studies have suggested that oligomers and protofibrils of α-synuclein are cytotoxic, and that pale bodies and LBs may represent a cytoprotective mechanism in PD.

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To explore pathogenesis of synucleinopathy including Parkinson's disease and multiple system atrophy, we developed cellular model for synucleinopathy. In this experimental model, α-synuclein was overexpressed in SH-SY5Y cells, which were then exposed to mitochondrial toxins. The data thus obtained suggested the followings.
1) By the treatment with rotenone, wild type α-synuclein overexpressing cells demonstrated intracellular aggregations, which shared a number of features with Lewy bodies.
2) The aggregate formation of α-synuclein may be cytoprotective.
3) The catechol-derived quinones are candidate molecules to facilitate the oligomer formation of α-synuclein.
4) The cells overexpressing S129A mutant showed few aggregations. It is suggested that phosphorylation at serine 129 is essential for aggregate formation.
5) In wild-type α-synuclein cells treated with rotenone, unfolded protein response (UPR) markers were induced prior to the induction of mitochondrial disruption and caspase-3 activation.
6) On the other hand, the S129A mutant failed to activate these UPRs. Thus it seems plausible that α-synuclein toxicity is dependent on the phosphorylation at S129.

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The prognosis of Parkinson's disease (PD) has been improved with developing anti-parkinsonian agents. Recently the re-evaluation of L-dopa and dopamine agonists is the topic in the world based on focusing non motor side effects of dopamine agonists such as sudden uncontrollable somnolence and valvulopathy in place of motor complication. The development of anti-parkinsonian drugs based on the new mechanism has been progressed such as CEP-1347, AAV-neuturin, AAV-GAD, and AAV-DDC. The most reliable new drug is zonisamide which is originally synthesized in Japan for epilepsy. A nation-wide randomized double blind study showed that Zonisamide improves motor function of advanced PD patients. Long-term efficacy was also shown. The mechanism of zonisamide for PD is the increase of dopamine synthesis and moderate inhibition of monoamine oxydase B activity. Inhibitatory effects of sodium channel and T-type calcium channel may also affects. Zonisamide has neuroprotective effects though inhibition of quinoprotein and increasing the levels of GSH and Mn SOD. Up to now we have no agents with clinically evidenced neuroprotective effects for PD. Base on the results of ELLDOPA study and "delayed start" clinical trials the most important concept for neuroprotection may be the early dopaminergic support for the degenerating dopaminergic system.

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Research on familial frontotemporal lobar degeneration (FTLD) has led to the discovery of disease-causing genes: microtubule-associated protein tau (MAPT), progranulin (PGRN) and valosin-containing protein (VCP). TAR DNA-binding protein of 43kDa (TDP-43) has been identified as a major component of tau-negative ubiquitin-positive inclusions in familial and sporadic FTLD and amyotrophic lateral sclerosis (ALS), which are now referred to as TDP-43 proteinopathy. Recent findings of mutations in TDP-43 gene in familial and sporadic ALS cases confirm the pathogenetic role for TDP-43 in neurodegeneration.
TDP-43 proteinopathies have been classified into 4 pathological subtypes. Type 1 is characterized by numerous dystrophic neurites (DNs), Type 2 has numerous neuronal cytoplasmic inclusions (NCIs), Type 3 has NCIs and DNs and Type 4 has neuronal intranuclear inclusions (NIIs) and DNs. There is a close relationship between such pathological subtypes of TDP-43 proteinopathy and the immunoblot pattern of C-terminal fragments of accumulated TDP-43. These results parallel our earlier findings of differing C-terminal tau fragments in progressive supranuclear palsy and corticobasal degeneration, despite identical composition of tau isoforms. Taken together, these results suggest that elucidating the mechanism of C-terminal fragment origination may shed light on the pathogenesis of several neurodegenerative disorders involving TDP-43 proteinopathy and tauopathy.

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Tau-negative and ubiquitin-positive inclusions (UPI) are the pathological hallmarks of frontotemporal lobar degeneration (FTLD-U) and amyotrophic lateral sclerosis (ALS). Recently, TDP-43, a heterogeneous nuclear ribonucleoprotein was identified as a component of these UPI. However, it remains to be determined whether TDP-43 is the major component of UPI, because only antibodies recognizing both normal and abnormal TDP-43 have been available. We raised antibodies to phosphopeptides representing 36 out of 64 candidate phosphorylation sites of human TDP-43. Of the generated antibodies, pS379, pS403/404, pS409, pS410 and pS409/410 clearly labeled UPI and glial cytoplasmic inclusions but not the nuclei. Immunoblot analyses of sarkosyl insoluble fractions demonstrated that the phosphorylation-specific antibodies recognized TDP-43 at -45kDa, smearing substances and the -25kDa fragment, all of which were present in the brains of FTLD-U and ALS but not controls. These antibodies did not recognize normal TDP-43 at 43kDa. These results clearly indicate that abnormally phosphorylated full-length TDP-43 and the C-terminal fragments are the major component of UPI in FTLD-U and ALS. These findings together with recent discovery of mutations in the TDP-43 gene in ALS strongly suggest that TDP-43 is the key molecule responsible for neurodegeneration in FTLD-U and ALS.

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Frontotemporal dementia (FTD) is a clinical phenotype of dementia, characterized by complex of clinical symptoms, including disinhibition, character change, increased appetite, sexual misconduct and language problems. Frontotemporal lobar degeneration (FTLD) is a pathological classification of neurodegenerative disorder and its core consists of Pick's disease (PiD). Historically, PiD was morphologically subclassified into three types, but recent immunocytochemical investigations defined type I as PiD with Pick bodies (three repeat tauopathy), type II as corticobasal degeneration (CBD, four repeat tauopathy) and type III as FTLD with ubiquitinated inclusions (FTLD-U). The recent progress provided an evidence that the majority of FTLD-U represented primary TDP 43 proteionopathy. Three major clinical phenotypes of FTLD consist of FTD, semantic dementia (SD) and progressive non-fluent aphasia (PNFA). Clinical and pathological correlative studies demonstrated that majority of the background pathology of FTD is PiD with Pick bodies, that of SD is FTLD-U and that of PNFA is CBD, although there are too many exceptions. Although FTD is one of the major clinical manifestations of FTLD, the most frequent pathological background of FTD is Alzheimer disease (AD). The degenerative processes causing FTD symptoms include dementia with Lewy bodies (DLB), progressive supranuclear palsy (PSP) and argyrophilic grain disease. Moreover, vascular process such as Binswanger disease and inflammatory process such as neurosyphilis could also present with FTD symptoms. Since FTD requires special clinical care distinct from AD, clinical diagnosis of FTD is quite important. But for the fundamental treatment based on background pathological processes, surrogate biomarkers, including structural and functional neuroimages and findings of cerebrospinal fluid, blood and urine, should be pursued for future progress in FTD research.

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Frontotemporal lobar degeneration (FTLD) is the third most common cause of cortical dementia, following Alzheimer disease and dementia with Lewy body.
Clinical criteria of FTLD were reviewed, and the initial symptoms, early neuropsychological and behavioral characteristics were also reviewed.
In our own 205 ALS patients, 20 patients were dementia with ALS. In those cases, early and progressive loss of social awareness and insight and paragraphia were frequently observed. In ALS patients, especially patients with bulbar symptoms, we must carefully examine the mental functions and study the brains with MRI and SPECT/PET for detection of frontotemporal dysfunction.

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Behavioral changes in patients with FTD can be interpreted by considering damage to the frontal lobes themselves and considering the interaction between the frontal lobes and other neural systems such as the posterior association cortices, the limbic system, and basal ganglia. Loss of insight and apathy primarily result from frontal lobes involvement. The latter is probably correlated with the severity of medial frontal-anterior cingulate involvement. Stimulus-bound behavior such as imitation behavior, utilization behavior and environmental dependency syndrome is caused by an imbalance between the activities of the frontal and parietal lobes. Frontal lobe damage, particularly damage to the medial frontal area, result in liberation of the parietal lobe activity, leaving the patient subject to any stimuli from the external environment. Disinhibition such as antisocial behavior is produced by an imbalance between the activities of the frontal and limbic lobes. Namely, loss of control of the frontal lobe, especially the orbitofrontal area, over the limbic system results in acts led by instinctive desires and uncontrolled by reason. Stereotypic behavior is due to an imbalance between the activities of the frontal cortex and basal ganglia. These behaviors range from simple stereotypies to complex repeated actions such as roaming, clock-watching or adherence to a strict daily timetable.

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Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a distinct clinical syndrome caused by mutations in mitochondrial DNA. Crucial molecular mechanism includes a lack of taurine modification at the wobble uridine of the mutant tRNA^{Leu (UUR)}, causing UUG condon-specific translational defect and mitochondrial protein synthesis failure. However, the pathogenesis of stroke-like episodes remains unknown.
We previously reported that stroke-like episodes were more likely non-ischemic events, characterized by increased capillary permeability, hyperperfusion, neuronal vulnerability and neuronal hyperexcitability, in which neuronal hyperexcitability plays an important role in initiation of the cascades of stroke-like events by increasing energy demand. We also emphasized a role of prolonged epileptic activities in progressive spread of stroke-like lesions, and then proposed a non-ischemic neurovascular cellular mechanism. Once neuronal hyperexcitability developed in a localized region as a result from either mitochondrial dysfunction in capillary endothelial cells, or in neurons or astrocytes, epileptic activities depolarize adjacent neurons, leading to propagation of epileptic activities in surrounding cortex. Increased capillary permeability in the presence of mitochondrial capillary angiopathy may cause unique edematous lesions predominantly involving the cortex. As a consequence, most susceptible layers of the cortex may result in neuronal loss. Therapeutic targets include each ongoing process of the disease.

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MELAS is the most dominant clinical features among mitochondrial disorders. However the natural course of MELAS has not been clarified yet. In order to elucidate the natural course of MELAS, we have done the Japanese Cohort study on MELAS. By the age of onset, we divided MELAS into two subgroups, a juvenile form (onset is less than 18 years of age) and an adult form (onset is more than 18 years of age). Juvenile form is significantly different from adult form not only in the mean age of onset, but the mean age of death and survival rate (juvenile has 3.2 times higher chance of death than adult). Our date indicate that juvenile form of MELAS is more severe and poor prognosis than those seen in adult form. Based on the hypothesis that MELAS is caused by impaired vasodilation in an intracerebral artery, we evaluated the effects of administering L-arginine, a nitric oxide precursor. Patients were administered L-arginine intravenously at acute phase, or per orally at interictal phase. L-arginine infusions significantly improved all stroke-like symptoms suggesting stroke within 30 min, and oral administration significantly decreased frequency and severity of stroke-like episodes. L-arginine therapy showed promise in treating stroke-like episodes in MELAS.

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Patient studies suggested that accumulation of pathogenic mitochondrial (mt) DNAs having large-scale deletion or point mutation and the resultant mitochondrial respiratory abnormalities are associated with a wide variety of disorders, such as mitochondrial diseases, neurodegenerative diseases, diabetes, and aging. Although the pathogenicities of these mtDNA mutations were proved by co-transmission of the mutant mtDNAs and respiration defects to human mtDNA-less cells, there is as yet no convincing reverse genetic evidence to explain whether accumulation of these pathogenic mutant mtDNAs in tissues is responsible for the expressions of various clinical phenotypes. In such situation, we have succeeded in generating mice with pathogenic deletion mutant mtDNA, named "mito-mice", by introduction of mitochondria with mtDNA which is deleted 4,696 bp (nt 7,759-12,454) including 6 tRNA genes and 7 structural genes (del-mtDNA). In the mito-mice, del-mtDNA was transmitted maternally, and its accumulation induced mitochondrial dysfunction in various tissues, resulting in mitochondrial disease phenotypes, such as low body weight, lactic acidosis, ischemia, myopathy, hart block, deafness, male infertility, and renal failure. Thus, mito-mice are the first model animal for mtDNA-based diseases, and the mice should be valuable for screening effective drugs and testing therapies.

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Mitochondrial diseases have a peculiar character of variability that expands from DNA, cell and tissue/organ levels to family/society level. These kinds of variability seem an obstacle to prevent us from developing new and effective therapies for this disease. Selective delivery system to mitochondria can make us get a promising new strategy to treat and prevent the disease. MITO-Porter may be a powerful system in which we can introduce a various kind of materials including DNA, RNA, enzyme and drugs to mitochondria in vivo.

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Hereditary neuropathies are classified into Charcot-Marie-Tooth disease (CMT), familial amyloid polyneuropathy (FAP), hereditary motor neuropathies (HMN) and hereditary sensory (and autonomic) neuropathies (HSAN). CMTs are furthermore classified into demyelinating neuropathies (CMT1), axonal neuropathies (CMT2) and intermediate form. Duplication of PMP22 (CMT1A) accounts for about 70% of CMT1 and MFN2 mutations account for 25% of CMT2. Genes involved in phosphoinositide regulation cause CMT4; MTMR2 mutation in CMT4B1 and MTMR13/SBF2 mutation in CMT4B2. In addition to these genes, FIG4, which is a causative gene of pale tremor mouse, is newly identified as a gene for CMT4J. MFN2 and GDAP1 cause CMT2 or CMT4. These genes regulate mitochondrial fusion and fission. Altered axonal mitochondrial transport is suggested as the pathogenesis of the CMT. In animal model with pmp22 duplication, ascorbic acid seems to be effective to prevent disease progression. Nationwide trial of ascorbic acid therapy for CMT1A is now ongoing by the intractable neuropathy study group. Curcumin treatment educes apoptosis of cells that express PMP22 point mutation and partially mitigates the severe neuropathy phenotype of Trembler-J mouse model in a dose-dependent manner. Curcumin treatment may have a potential therapeutic role in CMT with PMP22 point mutation in humans. The high throughput system of diagnosis for CMT has been developed by employing a resequencing array system.

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Guillain-Barré syndrome (GBS) has two types; acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). Recently, a nation-wide retrospective study showed that the rate of AMAN is higher in Japan than in western countries. A prospective study is now in progress. Elevated titers of serum anti-ganglioside antibodies are characteristic of GBS. Complement system has been shown to be involved in the anti-ganglioside antibody-mediated pathogenetic mechanisms. Some GBS patients have antibodies specific to a conformational epitope formed by two different gangliosides. Among such anti-ganglioside complex antibodies, anti-GD1a/GD1b IgG antibodies are shown to be associated with severe GBS requiring artificial ventilation. In contrast, antibodies highly specific to GD1b are associated with GBS with ataxia. Sensory ataxic neuropathy is induced by sensitization of rabbits with GD1b. An apoptotic mechanism has recently been shown to be involved in the pathogenesis of this animal model. Most of the patients with Fisher syndrome have anti-GQ1b IgG antibodies. Recent investigation on anti-ganglioside complex antibody showed that antibodies in Fisher syndrome can be subdivided into the three groups; GQ1b-specific, GQ1b/GM1-specific, and GQ1b/GD1a-specific. Research on antibodies to gangliosides and ganglioside complexes will provide us with a clue to develop a novel treatment of GBS.

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We assessed whether postgastrectomy polyneuropathy associated with thiamine deficiency is clinicopathologically identical to beriberi neuropathy, including a biochemical determination of thiamine status. The typical presentation for the two etiologies was as a symmetric sensorimotor polyneuropathy predominantly involving the lower limbs. In both groups, the main electrophysiologic findings were those of axonal neuropathy, most prominently in the lower limbs. Sural nerve biopsy specimens also indicated axonal degeneration in both groups. Subperineurial edema was commonly observed. Thiamine-deficiency neuropathies due to gastrectomy and dietary imbalance are identical despite variability in their clinicopathologic features and suggested that thiamine deficiency can be a major cause of postgastrectomy polyneuropathy. Characteristics of alcoholic neuropathy have been obscured by difficulty in isolating them from features of thiamine-deficiency neuropathy. We assessed 64 patients with alcoholic neuropathy including subgroups without and with coexisting thiamine deficiency. Thirty-two patients with nonalcoholic thiamine-deficiency neuropathy also were investigated for comparison. We concluded that pure-form of alcoholic neuropathy was distinct from pure-form of thiamine-deficiency neuropathy, supporting the view that alcoholic neuropathy can be caused by direct toxic effect of ethanol or its metabolites. However, features of alcoholic neuropathy is influenced by concomitant thiamine-deficiency state, having so far caused the obscure clinicopathological entity of alcoholic neuropathy.

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The blood-nerve barrier (BNB) is one of the functional barriers sheltering the nervous system from systemic blood. Although BNB is effective in controlling the endoneurial environment in normal condition, it may interfere the entrance of beneficial substances including various growth factors into the endoneurial space and inhibit the axonal regeneration in peripheral neuropathy. Since endothelial cells and pericytes of endoneurial microvascular origin are structural basis of BNB, investigation of the characteristics of these two cells using cell culture technique may provide novel strategies to modify BNB functions to promote peripheral nerve regeneration; however, no adequate cell lines possessing in vivo BNB characteristics were present so far. Recently we successfully established cell lines of endothelial cells and pericytes of endoneurial microvessel origin using transgenic rats harboring the temperature-sensitive simian virus 40 large T antigen. We also obtained immortal endothelial and pericyte cell lines originating from human BNB. Analyses of physiological characteristics and protein profiles in these BNB-forming cells are underway in our laboratory.

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