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Biomedical subjects

I Nakano

Publications and source records attributed to I Nakano.

At least 109 records · Page 6Linked to original sources

[A case report of dementia with cluttering-like speech disorder and apraxia of gait].

A 57-year-old woman presented with a slowly progressive gait disturbance in 1992 (53 years of age). Over the next year, she gradually began to talk less, but her speech itself became more rapid than before. He speech was frequently too fast even for family members to understand. In 1997, she was admitted to our hospital. On admission, the patient was disoriented but able to follow simple verbal commands, to name things, and to write simple words. Neither apraxia, aphasia, hemispatial neglect, nor a corpus callosum disconnection syndrome was observed. There was no muscle weakness or atrophy. She showed a positive Babinski sign with mild spasticity in the legs and Gegenhalten, but no rigidity. Her speech was monotonous and abnormally fast (cluttering-like speech). Her speech became faster and faster toward the end of sentences, skipping several syllables or even words. She was unable to speak slowly and clearly, even when efforts were made to pace her speech to the speed set by the examiner. She was able to stand only with a wide base of support and body flexion. When standing, she was unable to place one foot directly beside the other; as she tried to have one foot near the other, the former repelled the latter. She had great difficulties in taking her first step forward, and showed rapid freezing of gait even when she managed to succeed in starting. She was able to imitate walking or bicycling with her legs unloaded, indicating that her gait disturbance was a kind of apraxia of gait. Her intelligence was somehow difficult to assess because of her peculiar speech disturbance. However, her family members had noticed her memory disturbance and personality change (offensiveness) since 3 to 4 years before the admission. Moreover, she was defective not only on Hasegawa Damentia Scale-Revised but also on Raven's Colored Progressive Matrices which estimates non-verbal intelligence. It was also noted that she was inattentive and lazy in thinking on questionnaires. Thus we considered that she was at least mildly demented and the type of dementia was of frontal pathology. Laboratory data were all normal except for the head MRI, which demonstrated prominent and thinness of the corpus callosum from the anterior part of the body to splenium without any other brain lesions that could cause the thinness secondarily. Our case resembles two cases reported by Sunohara et al in 1985, together comprising a unique clinical feature. Although Sunohara et al did not refer to the thinness of the corpus callosum in their cases, the clinical profiles in our case and theirs raise the possibility that they form a new disease entity. A further study in a large number of similar cases, including autopsies will provide a conclusion.

Apraxias↗

[Polymicrogyria].

Explore the source record for details and available documents.

Cerebral Cortex↗

[A case of abulia without memory disturbance due to infarction of the bilateral genua of the internal capsules].

A 68-year-old right handed man with treated hypertension presented with acute-onset somnolence without hemiparesis, dysarthria or sensory disturbance. Although he became laconic and his verbal responses were only in short terms, his replies were accurate and judgmental. A cranial MRI in axial, coronal, and sagittal section revealed small hemorrhagic infarcts essentially limited to the bilateral capsular genua without involvement of the inferior thalamic peduncles. A 123I-IMP single photon emission CT disclosed remarkable hypoperfusion in the bilateral frontal cortex. After a week of somnolence, he gradually became wakeful, but was still abulic. Neuropsychological examinations revealed no memory disturbance. We consider that disconnection of the thalamo-frontal projection at the genua of the internal capsules caused somnolence, apathy, and abulia in our case. The hitherto reported cases of the genu infarcts that showed memory disturbance had the lesion involving both the inferior thalamic peduncle and its nearby mamillothalamic tract. In contrast, our case without memory disturbance had infarcts confined to the genua apparently sparing the two tracts, implicating that memory function may be preserved when such structures are intact.

Aged↗

[Habitual mandibular dislocation in two patients with Parkinson's disease].

There have been few case reports of mandibular dislocation in Parkinson's disease (PD) so far. We experienced habitual mandibular dislocation in two PD patients. They were a 74-year-old woman and a 56-year-old man, who were both graded V by Hoehn and Yahr's staging and had a 13- and 14-year history of PD, respectively. Remarkable retroflexion and rigidity of the neck was observed in both patients. Anterior dislocation of the jaw occurred without any special cause. Once the jaw was dislocated, it required unexpected power to reduce the dislocation against the rigidity. In a case of postencephalitic parkinsonism, continuous parkinsonian tremors of the mandible over a long period was indicated as a cause of the recurrent dislocation seen in the patient. No mandibular tremor, however, was observed in the present cases. The common feature of our two patients was retroflexion of the neck, which was assumed to make the suprahyoid muscles stretched and the mouth opened widely, causing the recurrent mandibular dislocation. Since the recurrence was prevented by chin cap, early chin cap therapy for the mandibular dislocation in parkinsonian patients is recommended.

Aged↗

[Neuropathology of amyotrophic lateral sclerosis--from basic findings to topics].

Amyotrophic lateral sclerosis (ALS) is a relentlessly progressive neurodegenerative disease that selectively affects upper and low motor neurons (UMNs and LMNs). The remaining LMNs show, in addition to normal appearance, a variety of cell pathology such as central chromatolysis, atrophy of the cell body and processes, Bunina bodies, and ubiquitinated hyaline and skein-like inclusions. Ultrastructural studies of the last two profiles indicate their processing by lysosomes. Whether apoptosis is responsible for motoneuronal death in ALS or not remains to be determined. In Klüver-Barrera (KB) staining, the pyramidal tracts in ALS usually appear normal at the pons in spite of their obvious pallor at the lower levels, leading to the dying-back hypothesis. However, axonal staining in such cases reveals obvious loss of large axons in the pontine pyramidal tracts, a finding inconsistent with the hypothesis. Similarly, in cases of motoneuron disease with the pyramidal tracts well stained by KB method, therefore, 'spinal progressive muscular atrophy (SPMA)', axonal staining demonstrated patent loss of large axons there. Thus, reappraisal seems to be required for previously reported SPMA cases, whose pathological diagnosis used to be made by KB staining alone.

Amyotrophic Lateral Sclerosis↗

Is endothelin-1 an aggravating factor in the development of acute pancreatitis?

OBJECTIVE: We have reported previously that cerulein-induced edematous pancreatitis would transform into hemorrhagic pancreatitis by administration of endothelin-1 in rats. In the present study, we tried to protect rat model from developing into hemorrhagic pancreatitis with BQ123 (an ETA receptor antagonist). METHODS: The rat model was made by 5-hour restraint water-immersion stress and two intraperitoneal injections of cerulein (40 micrograms/kg) at hourly interval. BQ123 (3 or 6 mg/kg) was administered intravenously 30 minutes before and 2 hours after the first cerulein injection. RESULTS: Acute hemorrhagic pancreatitis was induced in all rats treated with cerulin + stress. The score for pancreatic hemorrhage was 2.4 +/- 0.2 in this group. In the rats pretreated with BQ123, the score was reduced to 1.0 +/- 0.0, pancreas wet weight and serum amylase activity were significantly reduced, and histologic alterations in the pancreas lightened, also the local pancreatic blood flow improved without affecting the systemic blood pressure. CONCLUSIONS: These results suggest that endothelin-1 should play a role in aggravating the development of acute hemorrhagic pancreatitis, through its action on the pancreatic microcirculation.

Acute Disease↗

Behavioral recovery in 6-hydroxydopamine-lesioned rats by cotransduction of striatum with tyrosine hydroxylase and aromatic L-amino acid decarboxylase genes using two separate adeno-associated virus vectors.

Parkinson's disease (PD) is characterized by the progressive loss of the dopaminergic neurons in the substantia nigra and a severe decrease in dopamine in the striatum. A promising approach to the gene therapy of PD is intrastriatal expression of enzymes in the biosynthetic pathway for dopamine. Tyrosine hydroxylase (TH) catalyzes the synthesis of L-dopa, which must be converted to dopamine by aromatic L-amino acid decarboxylase (AADC). Since the endogenous AADC activity in the striatum is considered to be low, coexpression of both TH and AADC in the same striatal cells would increase the dopamine production and thereby augment the therapeutic effects. In the present study, the TH gene and also the AADC gene were simultaneously transduced into rat striatal cells, using two separate adeno-associated virus (AAV) vectors, AAV-TH and AAV-AADC. Immunostaining showed that TH and AADC were coexpressed efficiently in the same striatal cells in vitro and in vivo. Moreover, cotransduction with these two AAV vectors resulted in more effective dopamine production and more remarkable behavioral recovery in 6-hydroxydopamine (6-OHDA)-lesioned rats, compared with rats receiving AAV-TH alone (p < 0.01). These findings suggest an alternative strategy for gene therapy of PD and indicate that the simultaneous transduction with two AAV vectors can extend their utility for potential gene therapy applications.

Animals↗

Characterization of human monoclonal antibodies specific to the hepatitis C virus glycoprotein E2 with in vitro binding neutralization properties.

Both linear and conformational determinants of hepatitis C virus (HCV) are believed to be involved in viral neutralization. After immortalization of B cells from HCV chronically infected patients with Epstein-Barr virus, we obtained two polyclonal lymphoblastoid cell lines (LCL) secreting human monoclonal antibodies (HMabs). One clone was derived from a patient infected with a genotype 4 isolate while the second was isolated from a genotype 1b-infected patient. Immunoprecipitation studies, Western blot, and immunofluorescence analysis, peptide scanning, and ELISA studies indicated that the HMabs (1) recognized conformation-dependent determinant(s), (2) were capable of recognizing genotype 1a and 1b derived antigens, and (3) were able to precipitate noncovalently associated E1E2 complexes believed to exist on the surface of virion particles. The HMab derived from the genotype 4-infected patient was in addition shown to neutralize the in vitro binding of recombinant E2 protein onto susceptible cells suggesting a potential for in vivo neutralization. These data indicate that anti-E2 antibodies directed at conserved conformational-dependent determinant(s) exist in chronic HCV infection.

Antibodies, Monoclonal↗

A Japanese family with spinocerebellar ataxia type 6 which includes three individuals homozygous for an expanded CAG repeat in the SCA6/CACNL1A4 gene.

We describe a Japanese family which includes 13 patients in five generations who have dominantly inherited ataxia. Molecular testing revealed that in these patients the SCA6/CACNL1A4 gene carries the smallest known expanded CAG repeat (21 repeat units). The clinical features of these patients exhibited predominantly cerebellar ataxia with onset late in adult life and a very slowly progressive disease course. In addition, this SCA6 family showed some characteristic clinical and genetic features, including (1) apparent lack of genetic anticipation, with an intergenerationally stable CAG repeat size and (2) down-beat nystagmus and diabetes mellitus in some of the SCA6 patients. We identified three individuals homozygous for an expanded CAG repeat (21/21) in the SCA6/CACNL1A4 gene, two of whom were symptomatic. There were no apparent differences in clinical phenotype between the individuals homozygous and those heterozygous for an expanded CAG repeat in the SCA6/CACNL1A4 gene.

Aged↗

Effects of repeated systemic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to mice on interleukin-1beta and nerve growth factor in the striatum.

Interleukin (IL)-1beta and nerve growth factor (NGF) were measured for the first time in the brain (caudate nucleus and putamen, and frontal cortex) from control mice and mice treated with a parkinsonism-inducing neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), by highly-sensitive sandwich enzyme-linked immunosorbent assays (ELISAs) The concentrations of interleukin (IL)-1beta in the striatal regions were significantly higher in MPTP-treated mice than those in control mice treated with saline (P < 0.005), whereas those in the frontal cortex did not show significant differences between MPTP-treated and control mice. The present results agreed with our previous data on increased IL-1beta in the postmortem striatum from patients with Parkinson's disease (PD). In contrast, the concentrations of nerve growth factor (NGF) in the striatal regions were significantly lower in MPTP-treated mice, down to a 54% level of control mice (P < 0.05), but those in the frontal cortex did not show significant differences between MPTP-treated and control mice. Since NGF may play important roles as neurotrophic factors in the brain, the present results suggest that both the elevation of pro-inflammatory cytokine IL-1beta and the decrease of NGF in the dopaminergic striatal region of MPTP- treated mice may be related to neuronal cell death.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗

Prevention of dopaminergic neuron death by adeno-associated virus vector-mediated GDNF gene transfer in rat mesencephalic cells in vitro.

Glial cell line-derived neurotrophic factor (GDNF) is known as a potent neurotrophic factor for dopaminergic neurons. Since adeno-associated virus (AAV) vector is a suitable vehicle for gene transfer into neurons, rat E14 mesencephalic cells were transduced with an AAV vector expressing GDNF. When compared with mock transduction, a larger number of dopaminergic neurons survived in AAV-GDNF-transduced cultures (234% and 325% of controls at 1 and 2 weeks, respectively; P < 0.01). Furthermore, the dopaminergic neurons in the latter cultures grew more prominent neurites than those in the former. These findings suggest that AAV vector-mediated GDNF gene transfer may prevent dopaminergic neuron death, and is therefore a logical approach for the treatment of Parkinson's disease.

Animals↗

Maternal anticipation in Machado-Joseph disease (MJD): some maternal factors independent of the number of CAG repeat units may play a role in genetic anticipation in a Japanese MJD family.

We studied the relationship between the number of CAG repeat units in the MJD1 gene and clinical features of Machado-Joseph disease (MJD) in eight patients from two generations of a Japanese MJD family. Because of lack of characteristic clinical signs of MJD such as dystonia, bulging eyes or facial myokymia, clinical diagnosis of MJD in this family was difficult to make prior to molecular testing for the CAG repeat expansion in the MJD1 gene. All the patients exhibited maternal transmission of MJD, and the intergenerational change in the number of CAG repeat units in the MJD1 gene was very small (+0.5+/-0.3, mean+/-S.E.M., n=4) in spite of marked genetic anticipation (-17.0 years/generation). In the present family, the degree of anticipation per repeat unit in maternal transmissions was much larger than that in maternal transmissions in the other six MJD families. This indicates that some maternal factors other than the increase of the number of CAG repeat units, which is known to be the basis of anticipation, may play a role in genetic anticipation in this MJD family.

Adult↗

Modulation of immune responses to hepatitis C virus envelope E2 protein following injection of plasmid DNA using single or combined delivery routes.

Different delivery routes of plasmid DNA may result in the induction of differential humoral and cellular immunity. We have studied the influence of two main routes of plasmid injection, performed intramuscularly and intraepidermally using a gene gun, for the induction of immune responses specific to hepatitis C virus (HCV) envelope protein E2. Three plasmids expressing different immunogenic domains of E2 (amino acids [aa] 384443, aa 504-555, and aa 384-746) were injected into BALB/c mice according to five different protocols using various combinations of intramuscular (i.m.) or intraepidermal (i.e.) primary and booster injections. Seroconversion rates, antibody titers and isotypes, epitope recognition, and T-helper (Th) release cytokine profiles were analyzed. Antibody titers and epitope recognition were linked to either or both the nature of the immunogen expressed and the delivery route chosen. In all cases, the lowest antibody titers were obtained using single i.m.-based protocols. Independently of the antibody titers generated, only some specific i.e.-combined delivery routes induced antibodies able to recognize determinants located in the N-terminal of E2 (aa 384411 and aa 411437) and mimicked by synthetic peptides. By contrast, the antibody isotypes and the splenic cytokine production identified were independent of the plasmids used and the delivery route implemented. All conditions resulted in Th-1 like responses suggested by the exclusive detection of IgG2a and 2b antibodies and the production of interferon gamma (INF-gamma) but no interleukin-4 (IL-4). Overall, our results suggest that the combination of i.m. and i.e. delivery routes provides the most efficient way to induce a broad immune response against HCV-E2.

Animals↗

Loss of the dentate nucleus neurons is associated with torpedo formation: a morphometric study in progressive supranuclear palsy and dentatorubro-pallidoluysian atrophy.

Cerebellar torpedoes can be induced by direct damage to Purkinje cell axons. This raises the possibility that the loss of dentate nucleus neurons (DNNs) may also cause torpedo formation through synaptic detachment between DNNs and Purkinje cell axon terminals. To investigate this possibility, we conducted a morphometric study with an image analyzer in progressive supranuclear palsy (PSP) and dentatorubro-pallidoluysian atrophy (DRPLA). Using horizontal and sagittal sections of the cerebellar hemispheres containing the greatest proportion of the dentate nucleus, we determined the line densities of torpedoes, Purkinje cells, and DNNs. In PSP and DRPLA, the densities of DNNs were significantly lower, and the densities of torpedoes much greater than in controls, while those of Purkinje cells were normal in both diseases. In addition, the torpedo densities in PSP and DRPLA showed a strong negative correlation with the DNN densities. Thus, this study clearly demonstrated that torpedoes are formed in association with the loss of DNNs, suggesting that they may occur in consequence of synaptic disconnection of Purkinje cells from DNNs.

Adult↗

Assessment and treatment of liver disease in Japanese haemophilia patients.

We studied the prevalence of the hepatitis C virus (HCV), human immunodeficiency virus (HIV) and GB virus C or hepatitis G virus (GBV-C/HGV), and characteristics of infections in Japanese haemophilia patients. Haemophilia patients were highly infected with HCV (88.2%) because of frequent use of unheated blood concentrates. Analysis for HCV genotypes revealed characteristics of HCV infection in haemophilia patients. Japanese haemophilia patients were highly infected with rare genotypes in Japan: genotype 1a (26.5%), genotype 3 (14.5%) and genotype 4 (2.4%). HIV infection was observed in 32.3% of haemophilia patients. HCV quasispecies (clones) and direct sequencing were investigated in patients with a single HCV genotype in the hypervariable region 1 of HCV, which resulted in a high degree of diversity. This indicates that even a single genotype of HCV might have multiple origins. GBV-C/HGV infection was noted in 20.9% of Japanese haemophilia patients. Over 40 haemophilia patients with chronic hepatitis C have been treated with interferon alpha for 6 months at total doses of 480-720 million units. About 38% showed clearance of HCV RNA from serum. Six patients with HIV infection were included in the study and they did not show eradication of HCV from the serum. This might derive from that they had high serum HCV RNA titers and genotype 1a or 1b. Histologic assessment was performed in 36 haemophilia patients with HCV. No case showed a histologically normal liver. Hepatic fibrosis in the biopsy specimens was classified into five stages of fibrosis and compared with serum hepatic fibrosis markers. Serum hyaluronic acid mostly correlated with hepatic fibrosis (r = 0.78, P < 0.0001) followed by type IV collagen (r = 0.38, P < 0.05). This suggests that estimation of serum fibrosis markers might be substituted for liver biopsy in haemophilia patients.

HIV Infections↗