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O Onodera

Publications and source records attributed to O Onodera.

At least 55 records · Page 3Linked to original sources
PubMed1996

Association study between schizophrenia and dopamine D3 receptor gene polymorphism.

Crocq et al. [1992: J Med Genet 29:858-860] reported the existence of an association between schizophrenia and homozygosity of a BalI polymorphism in the first exon of the dopamine D3 receptor (DRD3) gene. In response to this report, further studies were conducted; however, these studies yielded conflicting results. In the present study, we examined 100 unrelated Japanese schizophrenics and 100 normal controls to determine any association between this polymorphism and schizophrenia. Results suggest that neither allele nor genotype frequencies of the DRD3 gene in the schizophrenics as a whole are significantly different from those of the controls. Further, we found no association between any allele or genotype and any clinical subtype based on family history of schizophrenia and age-at-onset. A significantly high frequency of homozygosity of a dopamine D3 receptor gene allele was not observed in the schizophrenics as a whole, or in clinical subtypes. Our results suggest that an association between the dopamine D3 receptor gene and schizophrenia is unlikely to exist.

Adolescent↗
PubMed1996

Lack of association between dopamine D2 receptor gene Cys311 variant and schizophrenia.

Itokawa et al. [1993] reported identifying one missense nucleotide mutation from C to G resulting in a substitution of serine with cysteine at codon 311 in the third intracellular loop of the dopamine D2 receptor in schizophrenics. Arinami et al. [1994] reported finding a positive association between the Cys311 variant and schizophrenia. In response to the report by Arinami et al. [1994] we examined 106 unrelated Japanese schizophrenics and 106 normal controls to determine if there is any association of the Cys311 variant with schizophrenia. However, we found no statistically significant differences in allelic frequencies of Cys311 between schizophrenia and normal controls. The present results as well as those of all previous studies except for that of Arinami et al. [1994] indicated that an association between the dopamine D2 receptor gene and schizophrenia is unlikely to exist.

Adolescent↗
PubMed1996

Lack of association of very low density lipoprotein receptor gene polymorphism with Caucasian Alzheimer's disease.

To determine whether the association of the very low density lipoprotein receptor (VLDL-R) gene with Alzheimer's disease (AD), which has recently been identified in Japanese AD patients, is commonly observed in AD patients of other ethnic backgrounds, we have investigated the allele frequency of the polymorphic CGG repeat in the 5'-UTR of the VLDL-R gene using a data set of 84 Caucasian AD patients with 104 Caucasian controls. Although the allele frequency of the 8-repeat allele was slightly lower, and that of 9-repeat allele was slightly higher, in the Caucasian AD patients than in Caucasian controls, the differences were not statistically significant. Multiple logistic regression analysis using apolipoprotein E4 (APOE4) allele, 5, 8-, or 9-repeat allele of the VLDL-R gene, sex, and age at onset as the predictors revealed that only the APOE4 allele was significantly associated with AD in the data set of the Caucasian AD patients and controls.

Aged↗
PubMed1996

Non-Mendelian transmission in dentatorubral-pallidoluysian atrophy and Machado-Joseph disease: the mutant allele is preferentially transmitted in male meiosis.

Autosomal dominant dentatorubral-pallidoluysian atrophy (DRPLA) and Machado-Joseph disease (MJD) are neurodegenerative disorders caused by CAG trinucleotide repeat expansions. An inverse correlation of age at onset with the length of the expanded CAG trinucleotide repeats has been demonstrated, and the intergenerational instability of the length of the CAG trinucleotide repeats, which is more prominent in paternal than in maternal transmissions, has been shown to underlie the basic mechanisms of anticipation in DRPLA and MJD. Our previous observations on DRPLA and MJD pedigrees, as well as a review of the literature, have suggested that the numbers of affected offspring exceed those of unaffected offspring, which is difficult to explain by the Mendelian principle of random segregation of alleles. In the present study, we analyzed the segregation patterns in 211 transmissions in 24 DRPLA pedigrees and 80 transmissions in 7 MJD pedigrees, with the diagnoses confirmed by molecular testing. Significant distortions in favor of transmission of the mutant alleles were found in male meiosis, where the mutant alleles were transmitted to 62% of all offspring in DRPLA (chi2 = 7.69; P<.01) and 73% in MJD (chi2 = 6.82; P<.01). The results were consistent with meiotic drive in DRPLA and MJD. Since more prominent meiotic instability of the length of the CAG trinucleotide repeats is observed in male meiosis than in female meiosis and meiotic drive is observed only in male meiosis, these results raise the possibility that a common molecular mechanism underlies the meiotic drive and the meiotic instability in male meiosis.

Adolescent↗
PubMed1996

Somatic mosaicism of expanded CAG repeats in brains of patients with dentatorubral-pallidoluysian atrophy: cellular population-dependent dynamics of mitotic instability.

Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disease caused by unstable expansion of a CAG repeat in the DRPLA gene. We performed detailed quantitative analysis of the size and the size distribution (range) of the expanded CAG repeats in various regions of the CNS of eight autopsied patients with DRPLA. Expanded alleles (AE) showed considerable variations in size, as well as in range, depending on the region of the CNS, whereas normal alleles did not show such variations, which indicates the occurrence of somatic mosaicism of AE in the CNS. The AE in the cerebellar cortex were consistently smaller by two to five repeat units than those in the cerebellar white matter. Moreover, the AE in the cerebral cortex were smaller by one to four repeat units than those in the cerebral white matter. These results suggest that the smaller AE in the cerebellar and cerebral cortices represent those of neuronal cells. The ranges of the AE in the cerebral cortex, cerebral white matter, and cerebellar white matter showed considerable variation ranging from 9 to 23 repeat units, whereas those in the cerebellar cortex showed little variance and were approximately 7 repeat units. The ranges of the AE in the cerebral cortex, cerebral white matter, and cerebellar white matter were much broader in patients with higher ages at death than they were in patients with lower ages at death, raising the possibility that the range of AE increases with time, as the result of mitotic instability of AE.

Adult↗
PubMed1995

Lack of association between dopamine D4 receptor gene and schizophrenia.

An intriguing property of the dopamine D4 receptor gene is a hypervariable segment in the coding region characterized by a varying number of direct imperfect 48 bp repeats (2-8 or 10 repeats) in the third exon of the gene [Lichter et al., 1993: Hum Mol Genet 2:767-773]. The authors analyzed 70 unrelated schizophrenics and 70 normal controls to determine the allele and genotype frequencies created by length polymorphism of dopamine D4 receptor gene. All patients and controls were unrelated and from the Japanese population. Patients were divided into three groups with regard to age at onset, familial loading, and severity of symptoms assessed strictly with Manchester scale. There were no statistically significant differences if the distributions of alleles and genotypes were analyzed for schizophrenia as a whole or analyzed in consideration of those clinical subtypes. Lichter and colleagues [1993] have reported that at least 25 haplotypes exist for this polymorphic region of the dopamine receptor D4 gene. In this study only the alleles created by length polymorphism were analyzed, and further investigation to determine the haplotypes of patients and controls on using a much larger sample size will be required.

Adolescent↗
PubMed1995

Dentatorubral-pallidoluysian atrophy: clinical features are closely related to unstable expansions of trinucleotide (CAG) repeat.

Dentatorubral-pallidoluysian atrophy is an autosomal dominant neurodegenerative disease characterized by various combinations of ataxia, choreoathetosis, myoclonus, epilepsy, and dementia as well as a wide range of ages at onset. A specific unstable trinucleotide repeat expansion in a gene on the short arm of chromosome 12 was recently identified as the pathogenic mutation for this disease. We investigated how the degree of expansion of the CAG repeat effects the clinical manifestations of dentatorubral-pallidoluysian atrophy. The size of the expanded alleles was well correlated with the age at onset (r = -0.696, p < 0.001). Patients with the progressive myoclonus epilepsy phenotype had larger expansions (62-79 repeats) and an earlier age at onset (onset before age 21). Furthermore, most of the patients with the progressive myoclonus epilepsy phenotype inherited their expanded alleles from their affected fathers. On the other hand, patients with the non-progressive myoclonus epilepsy phenotype showed smaller expansions (54-67 repeats) and a later age at onset (onset at or after age 21). Detailed analyses of clinical features demonstrated that ataxia, involuntary movement of either myoclonus or choreoathetosis, and intellectual decline are cardinal features of dentatorubral-pallidoluysian atrophy, with myoclonus and epilepsy being observed more frequently in patients with an earlier age at onset. Thus the wide variation in clinical manifestations of dentatorubral-pallidoluysian atrophy can now be clearly explained based on the degree of CAG repeat expansion, which strongly indicates that the expanded alleles are intimately involved in the neuronal degeneration in dentatofugal and pallidofugal systems.

Adolescent↗
PubMed1995

Trial to establish an animal model of paraneoplastic cerebellar degeneration with anti-Yo antibody. 1. Mouse strains bearing different MHC molecules produce antibodies on immunization with recombinant Yo protein, but do not cause Purkinje cell loss.

Passive transfer of anti-Yo antibody from patients with paraneoplastic cerebellar degeneration (PCD) associated with gynecological or breast carcinoma has not been successful in inducing an animal model. We used active immunization with recombinant Yo protein of four strains of mice bearing different MHC molecules: BALB/c (H-2d), C3H (H-2k), C57BL/6 (H-2b), SJL/J (H-2s). All the strains produced high anti-Yo antibody titer but none developed cerebellar ataxia or showed Purkinje cell loss. Spleen cells from the immunized mice also reacted with recombinant protein. Because C57BL/6(nu/nu) mice produce no anti-Yo antibody, mature helper T cells are required for its production. Results suggest that antibody production in peripheral blood alone is not sufficient for the development of PCD and that MHC class II molecules function in the activation of T cells to help B cells to help B cells produce antibodies.

Animals↗
PubMed1995

Trial to establish an animal model of paraneoplastic cerebellar degeneration with anti-Yo antibody. 2. Passive transfer of murine mononuclear cells activated with recombinant Yo protein to paraneoplastic cerebellar degeneration lymphocytes in severe combined immunodeficiency mice.

Passive transfer of serum IgG or mononuclear cells from peripheral blood of a patient with paraneoplastic cerebellar degeneration (PCD) to rodents was carried out in order to examine the role of anti-Purkinje cell antibody (anti-Yo antibody) present in serum and cerebrospinal fluid of PCD patients. After a single injection of IgG into mouse brain, it was taken up by Purkinje cells and remained there for more than 36 h without Purkinje cell loss. Injection of PCD IgG together with complement or lipopolysaccharide-activated human macrophages or rat mononuclear cells into rat ventricles did not cause Purkinje cell loss. We also studied passive transfer of the PCD patient's lymphocytes to mice with severe combined immunodeficiency (SCID). We constructed a recombinant Yo fusion protein that has the leucine-zipper protein (Yo protein), the common epitope for anti-Yo antibody for immunizing mice, and that resulted in production of significant amounts of anti-Yo antibody. Spleen cells from these Yo protein immunized mice were injected intravenously or intracerebrally into naive mice that subsequently showed no neurological symptoms or loss of Purkinje cells. We conclude that the anti-Yo antibody, either in combination with or without complement or activated mononuclear cells, cannot be the sole cause of Purkinje cell loss.

Adenocarcinoma↗
PubMed1995

Dentatorubral-pallidoluysian atrophy (DRPLA): close correlation of CAG repeat expansions with the wide spectrum of clinical presentations and prominent anticipation.

Dentatorubral-pallidoluysian atrophy (DRPLA) is a rare autosomal dominant neurodegenerative disease characterized by various combinations of ataxia, choreoathetosis, myoclonus, epilepsy and dementia as well as various ages of onset. We have identified a specific unstable trinucleotide repeat expansion in a gene on the short arm of chromosome 12 as the pathogenic mutation for DRPLA. We investigated how the degree of the expansion of the CAG repeat affects the clinical manifestations of DRPLA. The sizes of the expanded alleles were well correlated with the ages of onset (r = -0.6955, P < 0.001). Patients with progressive myoclonus epilepsy (PME) phenotype had larger expansions (62-79 repeats) and earlier ages of onset (onset before age 20). Furthermore, most of the patients with PME phenotype inherited their expanded alleles from their affected fathers. On the other hand, patients with non-PME phenotype showed later ages of onset (onset after age 20) and smaller expansions (54-67 repeats). When ages of onset of each clinical symptoms are compared with sizes of the CAG repeat, there is again a remarkably high correlation of the sizes of CAG repeat with each of the clinical symptoms. Thus the wide variation in clinical manifestations of DRPLA can now be clearly explained based on the degree of CAG repeat expansion, which strongly indicates that the expanded alleles are intimately involved in the neuronal degeneration in dentatofugal and pallidofugal systems.

Adult↗
PubMed1995

Genetic association of the very low density lipoprotein (VLDL) receptor gene with sporadic Alzheimer's disease.

A specific isoform of apolipoprotein E has been associated with the accelerated rate of disease expression of sporadic Alzheimer's disease (AD) and late-onset familial AD (FAD). An earlier age at onset has also been demonstrated in familial AD patients with mutations in the amyloid precursor protein (APP) gene (APP717 and APP670/671)13 carrying the APOE epsilon-4 allele compared to those who do not, but not in familial AD patients with APP692 or 693 mutations, or in chromosome 14-linked familial AD patients. Hypothesizing that receptors for apoE-containing lipoproteins act as a potential risk factor for AD, we performed an association study using a polymorphic triplet (CGG) repeat in the gene for the VLDL receptor (VLDL-R), a receptor for apoE-containing lipoproteins. The frequency of the 5-repeat allele was significantly higher in all of the Japanese sporadic AD patients (P < 0.02) than in the Japanese controls. Moreover, the odds ratio was significantly increased in the AD patients homozygous for the 5-repeat allele (OR = 2.1, 95% CI = [1.1-4.2]). Multiple logistic regression analysis reveals that the relative risk conferred by the presence of two copies of the 5-repeat allele and at least one copy of the APOE epsilon-4 allele is 8.7 (95% CI = [2.9-25.8]). Our results suggest that the VLDL-R gene is a susceptibility gene for AD.

Alleles↗
PubMed1995

Molecular cloning of a full-length cDNA for dentatorubral-pallidoluysian atrophy and regional expressions of the expanded alleles in the CNS.

Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disorder characterized by genetic anticipation and variable combinations of symptoms including myoclonus, epilepsy, cerebellar ataxia, choreoathetosis, and dementia. Recently, we discovered that DRPLA is caused by unstable expansion of a CAG repeat of a gene on the short arm of chromosome 12. We determined the consensus DRPLA cDNA sequence containing the complete coding region for 1,185 amino acids. The CAG repeat, which is expanded in DRPLA, is located 1,462 bp downstream from the putative methionine initiation codon and encodes a poly-glutamine tract. Although poly-serine and proline tracts exist near the CAG repeats, these polyserine or proline tracts did not show any polymorphisms, which is in strong contrast to the high heterogeneity in the length of the CAG repeat. Northern blot analysis revealed a 4.7-kb transcript that is widely expressed in various tissues including heart, lung, kidney, placenta, skeletal muscle, and brain. Reverse transcription-PCR analysis revealed that the expanded alleles are transcribed to levels comparable to those of normal alleles. These results indicate that there is no difference in transcriptional efficiency between expanded and normal alleles. Furthermore, mRNA from cerebellar hemispheres of DRPLA patients showed smaller sizes of CAG repeats compared with other regions of the brain, which reflects somatic mosaicism of the expanded alleles of the DRPLA gene.

Alleles↗
PubMed1995

[Auditory comprehension in transcortical motor aphasia due to a medial lesions of the left frontal lobe].

We assessed the anatomical findings and auditory comprehension of six patients with transcortical motor aphasia due to medical lesions of the left frontal lobe. All patients were right-handed and were initially mute for several hours after the onset, and they exhibited mild paresis of the right lower extremity. Their spontaneous speech was sparse and not fluent, and sometimes accompanied by echolalia, but their articulation was normal and repetition was excellent. They had difficulty in recalling words. A diagnosis of transcortical motor aphasia was made on the basis of their clinical symptoms. All patients were found to have an infarct in the left medial frontal region by MRI and/or CT. We administered the Western Aphasia Battery and 50 line drawing pointing task in order to evaluate auditory comprehension. Based on the results we concluded that there is no impairment of auditory comprehension of single words when lesions are limited to the superior frontal gyrus, but that lesions extending to the middle frontal gyrus interfere with auditory comprehension of single words. Our observations indicate that the middle frontal gyrus plays an important role in auditory comprehension of single words. All of the patients displayed impaired auditory comprehension of sentences even when their lesions were strictly limited to the medial frontal lobe. This suggests that the medial frontal lobe plays some role in the auditory comprehension of sentences.

Aged↗
PubMed1995

Dentatorubral-pallidoluysian atrophy (DRPLA). Molecular basis for wide clinical features of DRPLA.

Dentatorubral-pallidoluysian atrophy (DRPLA) is a rare autosomal dominant neurodegenerative disorder characterized clinically by various combinations of myoclonus, epilepsy, cerebellar ataxia, choreoathetosis, dementia and psychiatric symptoms. Based on the phenomenon of anticipation, the gene for DRPLA was recently identified. DRPLA is caused by unstable expansion of a CAG repeat in the gene located on the short arm of chromosome 12. As have been observed in Huntington's disease and SCA1, there is a strong correlation between the age of onset and the size of CAG repeats. Furthermore, patients with larger repeats tend to show a PME (progressive myoclonus epilepsy) phenotype as well as earlier ages of onset. More prominent anticipation and larger intergenerational increase of CAG repeats in paternal transmission can be accounted for by the meiotic instability of CAG repeats in male gametogenesis. Comparison of size distributions of CAG repeats in Japanese, African-American and white populations revealed that 7.4% of the Japanese alleles had greater than 19 repeats, whereas none of the whites and 1% of the African-American alleles were of this size. The results may account for the ethnic predilection of DRPLA.

Adult↗
PubMed1995

[Paraneoplastic cerebellar degeneration--characterization of anti-Yo antibody and underlying cancer].

A group of patients with paraneoplastic cerebellar degeneration (PCD) have shown to produce autoantibody to both neurons and tumor cells (anti-Yo antibody). More than 60% of these patients have shown neurological symptoms and anti-Yo antibody production before the underlying cancers were found, which suggests that the test for anti-Yo antibody is important for the early detection and treatment of cancer. Originally, anti-Yo antibody has been characterized as 1) labelling the cytoplasm of cerebellar Purkinje cells immunohistochemically, 2) binding to the 62 and 34kDa bands on immunoblots of Purkinje cell extracts, 3) being present in female patients with gynecological or breast cancers. Recently, the common binding-epitope of anti-Yo antibody has been reported as leucine-zipper protein. In order to detect the anti-Yo antibody precisely, we examined the immunohistochemical and western blot characters of the recombinant leucine-zipper protein-reactive (anti-Yo) antibody. The results were, 1) sera containing leucine-zipper protein-reactive antibody labels both cerebellar Purkinje cells but some sera might contain other antibodies together with anti-Yo that confuse the immunostaining character of anti-Yo antibody, 2) the antibody binds to 58 kDa band and sometimes co-binds to 34kDa on immunoblots of cerebellar tissue extracts. The underlying cancers are mainly adenocarcinoma in the ovary, fallopian tube, uterus, or breast but occasionally large cel lung and bile duct cancers have been found. Interestingly, a male patient had an antibody similar in character to be anti-Yo antibody immunohistochemically and on immunoblots, that did not recognize leucine-zipper protein and the underlying carcinoma was small cell lung cancer. These results suggest that 1) the diagnosis of anti-Yo antibody should be based on the antibody's reactivity with leucine-zipper protein, 2) some sera with the anti-Yo antibody label other tissues besides the Purkinje cell cytoplasm because of the co-existence of other antibodies seen immunohistochemically and on immunoblots, 3) the search for underlying cancers should not be limited to gynecological or breast carcinomas.

Adenocarcinoma↗
PubMed1994

Passive transfer and active immunization with the recombinant leucine-zipper (Yo) protein as an attempt to establish an animal model of paraneoplastic cerebellar degeneration.

Passive transfer of paraneoplastic cerebellar degeneration (PCD) IgG to rodents as well as active immunization with recombinant Yo fusion protein were tried in order to examine the roles of anti-Purkinje cell antibody (anti-Yo antibody) present in the sera and cerebrospinal fluid of patients with PCD in Purkinje cell loss, the hall mark of PCD pathology. On a single injection of PCD IgG to mouse brain, IgG was taken into Purkinje cells and remained there for more than 36 h without Purkinje cell loss. Injection of PCD IgG together with complement or lipopolysaccharide-activated human macrophages or rat mononuclear cells to rats ventricles did not cause Purkinje cell loss. We made a recombinant Yo fusion protein that has the leucine-zipper protein (Yo protein), the common epitope for anti-Yo antibody. Mice immunized with this Yo protein produced high titer antibody against it for more than 3 months, during which time neither neurological symptoms nor Purkinje cell loss occurred. The anti-Yo antibody, with or without complement or activated mononuclear cells, therefore could not be the sole cause of Purkinje cell loss.

Aged↗