Biomedical subjects

E Mori

Publications and source records attributed to E Mori.

At least 73 records · Page 4Linked to original sources

PubMed1999

A new beta subtype-specific interaction in alpha1A subunit controls P/Q-type Ca2+ channel activation.

The cytoplasmic beta subunit of voltage-dependent calcium channels modulates channel properties in a subtype-specific manner and is important in channel targeting. A high affinity interaction site between the alpha1 interaction domain (AID) in the I-II cytoplasmic loop of alpha1 and the beta interaction domain (BID) of the beta subunit is highly conserved among subunit subtypes. We describe a new subtype-specific interaction (Ss1) between the amino-terminal cytoplasmic domain of alpha1A (BI-2) and the carboxyl terminus of beta4. Like the interaction identified previously () between the carboxyl termini of alpha1A and beta4 (Ss2), the affinity of this interaction is lower than AID-BID, suggesting that these are secondary interactions. Ss1 and Ss2 involve overlapping sites on beta4 and are competitive, but neither inhibits the interaction with AID. The interaction with the amino terminus of alpha1 is isoform-dependent, suggesting a role in the specificity of alpha1-beta pairing. Coexpression of beta4 in Xenopus oocytes produces a reduced hyperpolarizing shift in the I-V curve of the alpha1A channel compared with beta3 (not exhibiting this interaction). Replacing the amino terminus of alpha1A with that of alpha1C abolishes this difference. Our data contribute to our understanding of the molecular organization of calcium channels, providing a functional basis for variation in subunit composition of native P/Q-type channels.

Amino Acid Sequence↗

PubMed1999

Diffusion-weighted magnetic resonance imaging: detection of ischemic injury 39 minutes after onset in a stroke patient.

A neurologist witnessed the in-hospital onset of an ischemic stroke in a 71-year-old right-handed male who suddenly developed global aphasia and right hemiplegia. Diffusion-weighted magnetic resonance imaging (DWI) 39 minutes after the ictus demonstrated high signals in the left internal carotid artery territory. T1- and T2-weighted images failed to detect this change. Magnetic resonance angiography showed occlusions in branches of the left anterior and middle cerebral arteries and an atheromatous stenotic lesion in the ipsilateral proximal internal carotid artery. The patient was treated with intravenous heparin and low molecular dextran solution. Repeated magnetic resonance imagings identified an infarction slightly smaller than the abnormality demonstrated by the initial DWI. DWI detects hyperacute ischemic injury within 1 hour of symptom onset in human ischemic stroke.

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PubMed1999

Molecular nature of RAPD markers from Haemophilus influenzae Rd genome.

Despite the widespread application of the random amplified polymorphic DNA (RAPD) technique, there is no experimental evidence of the molecular mechanism of random amplification starting from a complex template. To investigate this mechanism, we cloned and sequenced 23 selected RAPD bands amplified from Haemophilus influenzae Rd genomic DNA using eight decamer primers different in GC content and/or nucleotide sequence. As the whole genome sequence of H. influenzae Rd has been reported, the exact nucleotide sequence of each primer-template annealing site was identified. Results showed that, on an average, a homology of eight base pairs was involved in priming events and that the number of nonhomologous base pairings declined exponentially from the 5' end of the primer to its 3' end. The interaction between the primer and the template DNA was stabilized by the formation of secondary structures, and a perfect match of the 3' terminal region of the primer was not necessary for successful amplification. The complexity of the annealing process suggested that, in the studied reaction conditions, many primer-template annealing sites were extended in the first cycles and that differences in the efficiency of priming and replication processes led to amplification of RAPD fragments. Moreover, the distribution of the amplified regions on the H. influenzae chromosome was analyzed.

Base Sequence↗

PubMed1999

Hereditary sensory neuropathy with deafness and dementia: a clinical and neuroimaging study.

We describe three sibling patients with autosomal dominantly inherited sensory neuropathy, sensorineural hearing loss and dementia. The features of cognitive-behavioral deficits in the patients, including executive dysfunction, apathy, indifference and inattention, were consistent with a frontal lobe dysfunction. Magnetic resonance imaging showed a diffuse brain atrophy. A fluorodeoxyglucose positron emission tomography in one patient and a single photon emission computed tomography in another demonstrated a glucose hypometabolism or a hypoperfusion in the medial frontal and thalamic regions. Primary frontal involvement or frontal dysfunction secondary to thalamic lesions may contribute to the nature of dementia in these patients.

Deafness↗

PubMed1999

Tc-99m ethyl cysteinate dimer SPECT and 2-[F-18]fluoro-2-deoxy-D-glucose PET in Alzheimer's disease. Comparison of perfusion and metabolic patterns.

PURPOSE: This study compared Tc-99m ethyl cysteinate dimer (ECD) SPECT images with 2-[F-18]fluoro-2-deoxy-D-glucose (FDG) PET images in the same patients with Alzheimer's disease and determined whether ECD SPECT is as useful as FDG PET clinically. METHODS: Ten patients with probable Alzheimer's disease (mean +/- SD: age, 71 +/- 5.2 years; 6 women and 4 men; Mini-Mental State Examination score, 19.2 +/- 5.3) were evaluated in this study. Both ECD SPECT and FDG PET were performed within 1.5 months in each patient. RESULTS: ECD SPECT showed a reduction in parieto-temporal perfusion in 8 of the 10 patients, whereas FDG PET showed a reduction in temporoparietal metabolism in 9. The ECD images showed greater radiotracer uptake in the cerebellum and occipital lobe than did FDG images. The contrast between the radiotracer uptake in the sensorimotor area and that in the parietotemporal region was not as great in the ECD images as it was in the FDG images. CONCLUSION: Although ECD SPECT may not be superior to FDG PET, it is useful for the clinical evaluation of patients with Alzheimer's disease.

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PubMed1999

Violence and epilepsy: a close relation between violence and postictal psychosis.

PURPOSE: We investigated the incidence of well-directed violent behavior and suicide attempts in patients with temporal lobe epilepsy, with special attention to postictal psychosis. METHODS: We compared 57 episodes of postictal psychosis with 62 episodes of acute interictal (or alternative) psychosis and with 134 complex partial seizures. All patients were matched for age and for age at onset of seizures. RESULTS: The incidence of well-directed violent behavior against human beings was significantly higher (23%) during postictal psychotic episodes than during acute interictal episodes (5%) and postictal confusion (1%). Suicide attempts were also more frequent during postictal psychosis (7%) than during either acute interictal psychosis (2%) or postictal confusion (0%). CONCLUSIONS: Our study showed that well-directed violent and self-destructive behavior was not a feature of epileptic psychosis in general but a specific hallmark of postictal psychosis.

Adult↗

PubMed1999

Expression of Fas-Fas ligand in murine testis.

PROBLEM: During spermatogenesis, it has been suggested that the number of germ cells to be matured is regulated and restricted through the apoptotic mechanism. In the present study, we investigated the expression and apoptotic role of Fas and Fas ligand (L) in the murine testis. METHOD OF STUDY: The expression of Fas-FasL in the murine testis was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR)-Southern blot hybridization, in situ hybridization, and Western blot methods. The terminal deoxynucleotide transferase mediated dUTP-nick end label (TUNEL) and DNA fragmentation methods were applied to detect the generation of apoptosis in germ cells. RESULTS: By means of RT-PCR-Southern blot hybridization, we demonstrated the positive expression of Fas in testicular germ cells, and of FasL in testicular cells. supporting the findings with in situ hybridization that Fas was localized in germ cells, whereas FasL was localized in Sertoli cells of murine testis. A specific band at 45 kDa was obtained in the lysates from testis and germ cells with Western blot analysis. Then, the co-incubation of germ cells with Spodoptera frugiperda (Sf9)-FasL cells in vitro resulted in the induction of apoptosis in germ cells detected by the TUNEL method. Furthermore, DNA fragmented ladders were also demonstrated in germ cells co-incubated with Sf9-FasL cells. CONCLUSION: Fas-FasL system seemed to play an apoptotic role in spermatogenesis by the molecular interaction between FasL on Sertoli cells and Fas on germ cells.

Animals↗

PubMed1999

A randomly amplified polymorphic DNA marker specific for the Bacillus cereus group is diagnostic for Bacillus anthracis.

Aiming to develop a DNA marker specific for Bacillus anthracis and able to discriminate this species from Bacillus cereus, Bacillus thuringiensis, and Bacillus mycoides, we applied the randomly amplified polymorphic DNA (RAPD) fingerprinting technique to a collection of 101 strains of the genus Bacillus, including 61 strains of the B. cereus group. An 838-bp RAPD marker (SG-850) specific for B. cereus, B. thuringiensis, B. anthracis, and B. mycoides was identified. This fragment included a putative (366-nucleotide) open reading frame highly homologous to the ypuA gene of Bacillus subtilis. The restriction analysis of the SG-850 fragment with AluI distinguished B. anthracis from the other species of the B. cereus group.

Amino Acid Sequence↗

PubMed1999

p38 mitogen-activated protein kinase can be involved in transforming growth factor beta superfamily signal transduction in Drosophila wing morphogenesis.

p38 mitogen-activated protein kinase (p38) has been extensively studied as a stress-responsive kinase, but its role in development remains unknown. The fruit fly, Drosophila melanogaster, has two p38 genes, D-p38a and D-p38b. To elucidate the developmental function of the Drosophila p38's, we used various genetic and pharmacological manipulations to interfere with their functions: expression of a dominant-negative form of D-p38b, expression of antisense D-p38b RNA, reduction of the D-p38 gene dosage, and treatment with the p38 inhibitor SB203580. Expression of a dominant-negative D-p38b in the wing imaginal disc caused a decapentaplegic (dpp)-like phenotype and enhanced the phenotype of a dpp mutant. Dpp is a secretory ligand belonging to the transforming growth factor beta superfamily which triggers various morphogenetic processes through interaction with the receptor Thick veins (Tkv). Inhibition of D-p38b function also caused the suppression of the wing phenotype induced by constitutively active Tkv (TkvCA). Mosaic analysis revealed that D-p38b regulates the Tkv-dependent transcription of the optomotor-blind (omb) gene in non-Dpp-producing cells, indicating that the site of D-p38b action is downstream of Tkv. Furthermore, forced expression of TkvCA induced an increase in the phosphorylated active form(s) of D-p38(s). These results demonstrate that p38, in addition to its role as a transducer of emergency stress signaling, may function to modulate Dpp signaling.

Animals↗

PubMed1999

Case-control study of presenilin-1 intronic polymorphism in sporadic early and late onset Alzheimer's disease.

OBJECTIVE: Presenilin-1 is a major causative gene for early onset familial Alzheimer's disease, and the apolipoprotein E epsilon4 allele is a major genetic risk factor known to influence late onset and sporadic early onset Alzheimer's disease. The presenilin-1 1/1 genotype has recently been reported to be associated with sporadic Alzheimer's disease. The purpose of this study is to determine whether Alzheimer's disease is associated with presenilin-1 gene polymorphism and the apolipoprotein E genotype in an extended case-control study. METHODS: An examination was conducted on 217 patients with Alzheimer's disease, along with an equal number of age and sex matched controls derived from the same community in a Japanese population, by using a chi2 test for homogeneity and a logistic regression analysis. A meta-analysis of data from the literature on allele frequencies in Alzheimer's disease and control populations was used for comparison with the Japanese allele frequencies obtained in this study. RESULTS: The presenilin-1 allele-1 frequencies were similar in patients with early onset Alzheimer's disease (0.61) and younger controls (0.61), and in those with late onset Alzheimer's disease (0.63) and elderly controls (0. 63). We found no evidence for a possible association between the presenilin-1 polymorphism and the apolipoprotein E epsilon4 allele. However, the meta-analysis showed that the association between the presenilin-1 1/1 genotype and Alzheimer's disease was significant (Peto odds ratio=1.16, 95% confidence interval=1.04-1.31). CONCLUSIONS: These results suggest a subtle but positive association of presenilin-1 gene polymorphism with Alzheimer's disease, although Japanese data in this study which failed to support such a relation would indicate an ethnic variation.

Adult↗

PubMed1999

Failure to confirm a synergistic effect between the K-variant of the butyrylcholinesterase gene and the epsilon4 allele of the apolipoprotein gene in Japanese patients with Alzheimer's disease.

To confirm a synergistic effect between the polymorphic K variant of the butyrylcholinesterase (BChE-K) gene and the epsilon4 allele of the apolipoprotein E (APOE) gene in Alzheimer's disease, the frequency of the BChE-K allele was re-examined in a large series of Japanese patients with Alzheimer's disease and controls. Two hundred and three patients with Alzheimer's disease and 288 age and sex matched controls were genotyped by polymerase chain reaction and restriction fragment length polymorphism for BChE-K and APOE. No changes were found in the frequency of BChE-K, either in the Alzheimer's disease group as a whole (0.17 v 0.14; p=0.36) or in early (0.16 v 0.16; p=0.98) or late (0.17 v 0.13; p=0.24) onset patients compared with age matched controls. The study failed to confirm the findings of a previous study which found a significantly higher incidence of BChE-K in patients with Alzheimer's disease with APOE epsilon4 allele than in controls. In the Japanese population studied here, there was no association between BChE-K and Alzheimer's disease, nor an interaction between BChE-K and APOE epsilon4 allele.

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PubMed1999

Risk factors for silent cerebral infarcts in subcortical white matter and basal ganglia.

BACKGROUND AND PURPOSE: The purpose of this study was to clarify whether the relevant risk factors for silent cerebral infarcts (SCIs) in subcortical white matter (WM) are different from those in the basal ganglia (BG). METHODS: Subjects of this study were 219 adults without a history of stroke or transient ischemic attack and without any abnormality on a neurological examination who consecutively visited the neurology service in our hospital between January 1994 and November 1997 requesting medical evaluation for possible cerebrovascular diseases. Subjects included 141 men and 78 women ranging in age from 33 to 83 years (mean+/-SD, 63.2+/-9.5 years). We performed brain MRIs and cervical/cranial MR angiographies on all subjects. In this study, SCI was defined as a focal lesion >5 mm in diameter that was prolonged on both T2-weighted and proton density images. RESULTS: SCIs in the WM and/or BG were detected in 88 (40.2%) of the 219 subjects. No SCI >15 mm was observed in this series. Fifty of the subjects had SCIs only in the WM, 32 subjects had SCIs in both the WM and BG, and 6 subjects had SCIs only in the BG. Thus, 82 (93.2%) of 88 subjects with SCIs had lesions in the WM. Most subjects with SCIs in the BG also had SCIs in the WM. Multiple logistic regression analyses revealed that age, female sex, and hypertension were significant and independent predictors of SCIs in the WM, and that age, a history of ischemic heart disease, and carotid artery stenosis were significant and independent predictors of SCIs in the BG. CONCLUSIONS: The present study indicated that the relevant risk factors for SCIs in the WM and those for SCI in the BG were different. Our results suggest that SCIs are prone to first appear in the WM in association with aging and hypertension, and the additional appearance of SCIs in the BG predicts a progression of generalized atherosclerosis that is manifested in the carotid and coronary arteries.

Adult↗

PubMed1999

Amygdalar volume and emotional memory in Alzheimer's disease.

OBJECTIVE: Everyday experience suggests that highly emotional events are often the most memorable. Experimental work in animals and humans has demonstrated that the amygdaloid complex plays a crucial role in emotional memory, i.e., memory of events arousing strong emotions. The aim of this study was to elucidate the relationship between medial temporal damage and impaired memory of real-life emotional events in patients with Alzheimer's disease. METHOD: In 36 patients with probable Alzheimer's disease who experienced the 1995 earthquake in Kobe, Japan, memories of events surrounding the earthquake were examined as an index of emotional memory with the use of a semistructured interview, and amygdalar and hippocampal volumes were quantified by magnetic resonance imaging. The effects of the atrophy of these structures on recall performance were determined by multiple regression analysis. RESULTS: Irrespective of generalized brain atrophy and cognitive impairments, emotional memory was correlated more with normalized amygdalar volume (right and left averaged) than with normalized hippocampal volume. General knowledge of the earthquake was correlated with neither amygdalar nor hippocampal volume. CONCLUSIONS: The results indicate that impairment of emotional event memory in patients with Alzheimer's disease is related to intensity of amygdalar damage and provide evidence of the amygdala's involvement in emotional memory in humans.

Aged↗

PubMed1999

Lack of effect of apolipoprotein E E4 allele on neuropsychiatric manifestations in Alzheimer's disease.

The association between the apolipoprotein E epsilon 4 (APOE E4) allele and a wide spectrum of behavioral symptoms of Alzheimer's disease (AD) was investigated. Neither the severity nor the presence of any behavioral changes was associated with the number of APOE E4 alleles, even after controlling for the effects of age at onset, sex, education level, duration of illness, and severity of dementia. The findings do not support the hypothesis that neuropsychiatric manifestations of AD are different in patients with the APOE E4 allele.

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PubMed1999

Distinctive neurobehavioral features among neurodegenerative dementias.

The distinctive neuropsychiatric features of Alzheimer's disease (AD), dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD) were investigated by using the Neuropsychiatric Inventory. The patients with FTD had significantly more euphoria, aberrant motor activity, and disinhibition and significantly fewer delusions compared with the patients with AD or DLB. The patients with DLB had significantly more hallucinations compared with the AD or FTD patients. The findings clearly demonstrate that AD, DLB, and FTD have distinctive neuropsychiatric features, which may correspond to different patterns of cerebral involvement characteristic of these three major degenerative dementias.

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PubMed1999

Apoptotic cell death of human gastric tumor induced by nucleosides from CD57+HLA-DRbright natural suppressor cell line.

CD57+HLA-DRbright natural suppressor (57.DR-NS) cell line derived from human decidual tissue generated apoptosis in a human gastric carcinoma cell line (GCIY) but not in a human diploid normal cell line (WI-38). The factors released from 57.DR-NS cells were purified by thin-layer-chromatography (TLC) and separated by high performance liquid chromatography (HPLC) into six components. The physicochemical structures of the six components were determined as a series of nucleosides and their modified forms collectively termed in a previous study. They could generate apoptotic cell death of GCIY malignant target cells, but not disturb the viability of WI-38 normal target cells. The administration of AINs into GCIY tumor bearing SCID mice resulted in drastic suppression of tumor growth followed by the decrease in tumor size due to the occurrence of apoptosis in tumor tissues.

Animals↗

PubMed1999

Regional cerebral glucose metabolism and blood flow in a patient with Marchiafava-Bignami disease.

We report functional neuroimaging studies of a 54-year-old man with Marchiafava-Bignami disease (MBD). Glucose metabolic images obtained by [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography showed diffusely reduced whole brain metabolism and strongly decreased metabolism in the frontal and parietal lobes, orbital gyrus, and thalamus. Cerebral perfusion images showed a similarly decreased radioactivity pattern as the metabolic images. Functional neuroimages would be useful for understanding the pathophysiologic processes of MBD.

Alcohol-Related Disorders↗

PubMed1999

[Usefulness of endovascular grafting for abdominal aortic aneurysm].

The purpose of this study was to determine the usefulness of endovascular grafting for abdominal aortic aneurysm (AAA) compared to conventional open repair. During the period from May 1998 through to April 1999, 16 patients (control group) with AAA underwent conventional open surgery and 6 patients (stent group) underwent endovascular grafting. Surgical data including operative time and intraoperative blood loss did not differ between the two groups. However, the postoperative parameters including the initiation of oral intake, the onset of flatus and the permission to walk were significantly sooner in the stent group than the control group. The postoperative changes of coagulopathy-fibrinolytic factor were comparable between the two groups. We conclude that the endovascular grafting is minimally invasive compared to conventional open surgery. In addition, there was no consumption coagulopathy in the endovascular grafting. However, it was necessary to develop new approach with new devices in order to perform endovascular grafting more safely.

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