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Biomedical subjects

S Minoshima

Publications and source records attributed to S Minoshima.

At least 199 records · Page 11Linked to original sources
PubMed1993

Structure, expression and chromosomal localization of the gene encoding human 2',3'-cyclic-nucleotide 3'-phosphodiesterase.

Four human genomic DNA clones for 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNP) were isolated by screening a human genomic library with human CNP cDNA clones as probes. Restriction mapping and sequence analysis revealed that the human CNP gene is about 8.5 kb long and composed of four exons interrupted by three introns. There are two transcription start points and in human brain, two forms of CNP mRNA are produced from a single gene by alternative splicing, similar to mouse. A homology search of the 5'-flanking regions of exon 0 and exon 1 in the human CNP gene indicated the presence of oligodendroglia-specific elements and myelin basic protein transcription element (MBTE) motif, in addition to TATA-box-like sequences. Spot blot hybridization of flow-sorted human chromosomes with the 3'-noncoding region of the human CNP cDNA showed the localization of CNP to chromosome 17.

2',3'-Cyclic Nucleotide 3'-Phosphodiesterase↗
PubMed1993

Spatial working memory in humans as revealed by PET.

The concept of working memory is central to theories of human cognition because working memory is essential to such human skills as language comprehension and deductive reasoning. Working memory is thought to be composed of two parts, a set of buffers that temporarily store information in either a phonological or visuospatial form, and a central executive responsible for various computations such as mental arithmetic. Although most data on working memory come from behavioural studies of normal and brain-injured humans, there is evidence about its physiological basis from invasive studies of monkeys. Here we report positron emission tomography (PET) studies of regional cerebral blood flow in normal humans that reveal activation in right-hemisphere prefrontal, occipital, parietal and premotor cortices accompanying spatial working memory processes. These results begin to uncover the circuitry of a working memory system in humans.

Brain↗
PubMed1993

Structure and chromosomal localization of the gene encoding the human myelin protein zero (MPZ).

We describe the cloning, characterization, and chromosomal mapping of the human myelin protein zero (MPZ) gene. The gene is about 7 kb long and consists of six exons corresponding to the functional domains. All exon-intron junction sequences conform to the GT/AG rule. The 5'-flanking region of the gene has a TA-rich element (TATA-like box), two CAAT boxes, and a single defined transcription initiation site detected by the primer extension method. The gene for human MPZ was assigned to chromosome 1q22-q23 by spot blot hybridization of flow-sorted human chromosomes and fluorescence in situ hybridization. The localization of the MPZ gene coincides with the locus for Charcot-Marie-Tooth disease type 1B, determined by linkage analysis.

Base Sequence↗
PubMed1993

Structure and localization of the gene encoding human peripheral myelin protein 2 (PMP2).

Peripheral myelin protein 2 (PMP2) is a small, basic, and cytoplasmic lipid binding protein of peripheral myelin. In this paper, we describe the cloning, characterization, and chromosomal mapping of the human PMP2 gene. The gene is about 8 kb long and consists of four exons. All exon-intron junction sequences conform to the GT/AG rule. The 5'-flanking region of the gene has a TA-rich element (TATA-like box) and a single defined transcription initiation site detected by the primer extension method. The gene for human PMP2 was assigned to chromosome 8q21.3-q22.1 by spot hybridization of flow-sorted human chromosomes and fluorescence in situ hybridization.

Base Sequence↗
PubMed1993

Precise mapping of the EGF receptor gene on the human chromosome 7p12 using an improved fish technique.

The gene for epidermal growth factor receptor (EGFR) has been localized to the p14-p12 region of human chromosome 7 by somatic cell hybridization and radioisotope in situ hybridization techniques. In this paper, we report the precise mapping of the EGFR gene to the band p12 of chromosome 7 using a novel method in which fluorescence images from in situ hybridization and Q-banding are computer graphically merged. The novel procedure is described in detail.

Cells, Cultured↗
PubMed1993

Optimization of Butterworth filter for brain SPECT imaging.

A method has been described to optimize the cutoff frequency of the Butterworth filter for brain SPECT imaging. Since a computer simulation study has demonstrated that separation between an object signal and the random noise in projection images in a spatial-frequency domain is influenced by the total number of counts, the cutoff frequency of the Butterworth filter should be optimized for individual subjects according to total counts in a study. To reveal the relationship between the optimal cutoff frequencies and total counts in brain SPECT study, we used a normal volunteer and 99mTc hexamethyl-propyleneamine oxime (HMPAO) to obtain projection sets with different total counts. High quality images were created from a projection set with an acquisition time of 300-seconds per projection. The filter was optimized by calculating mean square errors from high quality images visually inspecting filtered reconstructed images. Dependence between total counts and optimal cutoff frequencies was clearly demonstrated in a nonogram. Using this nomogram, the optimal cutoff frequency for each study can be estimated from total counts, maximizing visual image quality. The results suggest that the cutoff frequency of Butterworth filter should be determined by referring to total counts in each study.

Brain↗
PubMed1993

GeneView: multi-language human gene mapping library with a graphical user interface.

GeneView is a newly developed human gene mapping library system that works on an X-Window platform. This system is designed for researchers who routinely utilize gene mapping data in the laboratory but are unfamiliar with computer technology. GeneView offers various features, including friendly user interface, fast operation and visualization facility. Genetic loci are displayed graphically with an idiogram. This system can be operated in multiple languages. A current version supports Japanese and English, and can be easily expanded to include other languages. A prototype of GeneView is now installed on a SPARC (Sun4) workstation. Because of the X-Window platform, GeneView should be compatible with various types of workstations.

Algorithms↗
PubMed1993

Human gene mapping and chromosome sorting by laser technology.

More than 30 human genes have been mapped by a combination of the fluorescent in situ hybridization (FISH) and spot blot hybridization in this laboratory for the past five years. Furthermore, the Keio strategy has been established for the molecular analysis of the human genome using flow-sorted human chromosomes.

Base Sequence↗
PubMed1993

Serum myeloperoxidase and serum cytokines in anti-myeloperoxidase antibody-associated glomerulonephritis.

Anti-MPO antibodies, serum MPO and cytokines were examined in 106 patients with glomerulonephritis. Twenty-three patients had anti-MPO antibodies and crescent formation; 17 had crescentic glomerulonephritis (CRGN) and the remaining 6 had focal segmental necrosis with less than 50% crescent formation in the observed glomeruli. Pauci-immune CRGN accounted for 28 of 43 CRGN cases. Anti-MPO antibody titers were significantly higher in the cellular crescent stage and their titers correlated well with the number of crescents. Clinical observation revealed that 11 of 18 patients with anti-MPO antibody-associated CRGN had a respiratory tract infection prior to the onset of overt glomerulonephritis. Serum MPO was detected in 20 of 23 patients with anti-MPO antibodies and the amounts of MPO were especially high in the cellular crescent stage and correlated with anti-MPO antibodies. TNF-alpha and IL-6 were also detected in the sera in parallel with the anti-MPO antibody titers. These data suggest that anti-MPO antibodies, TNF-alpha and IL-6, induced by the infection, may activate neutrophils and MPO itself released from neutrophils, may play an important pathogenetic role in glomerular capillary necrosis leading to CRGN.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1993

[Correlation 111In-labeled leukocyte scintigraphy with clinical and laboratory findings].

This study was evaluated relationship 111In-labeled leukocyte scintigraphy and clinical information and laboratory findings in twenty-four patients with bone infection and thirty-five patients with abdominal infection. Fifty-nine scintigrams were retrospectively reviewed and classified into positive or negative results. As the laboratory findings, C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR) at sixty minutes, and peripheral blood leukocyte counts (WBCC) were evaluated. Clinical information such as presence of fever and administration of antibiotics was also compared. No significant relationship between the scintigraphic results and clinical as well as laboratory findings was observed in bone infection patients. CRP levels in positive scintigraphic patients were significantly higher than those in negative scintigraphic patients in the abdominal infection group, otherwise the other indices were not correlated with the scintigraphic results. A few patients with slightly increased CRP (mostly chronic cases) did not show positive scintigrams, suggesting an increased false negative rate of leukocyte scintigraphy in such circumstances. These results suggest that it is inappropriate to determine the application of leukocyte scintigraphy depending on clinical as well as laboratory findings, and leukocyte scintigraphy would yield additional information different from other indices when evaluating inflammatory foci.

Abdomen↗
PubMed1993

[Application of the chromosome sorting technique to the human genome analysis].

The flow-sorted human chromosome is an ideal DNA source for genome analysis research, particularly gene mapping and construction of cosmid library. For gene mapping, 50,000 chromosomes each were sorted on a membrane filter and hybridized with a radio-labeled gene probe. Using this Spot Blot Hybridization method in combination with FISH, we have mapped more than 30 new genes including 6 neuron-specific ones. For construction of a chromosome-specific cosmid library, nearly 10 million chromosomes were flow-sorted. The chromosome 21-specific cosmid library consisting of 33,000 clones and the 22pter-q11 region-specific library consisting of 9,200 clones were established. Grouping of cosmid clones from the library using high density replica filters and YAC DNAs to make cosmid contigs within specific regions is under way.

Base Sequence↗
PubMed1993

Automated detection of the intercommissural line for stereotactic localization of functional brain images.

A technique has been developed for automated detection of the intercommissural (AC-PC) line for positron emission tomography (PET). The AC-PC line is estimated from the location of four internal landmarks; the frontal and occipital poles, the inferior aspect of the anterior corpus callosum, and the subthalamic point. The landmarks are detected automatically in PET mid-sagittal slices by combining edge detection, interpolation and profile curve analysis techniques. The anatomical relationships between the true and estimated AC-PC lines from the landmarks was confirmed by analysis of magnetic resonance (MR) images. Accuracy of the automated estimation technique was assessed in co-registered PET and MR images, which showed minimal angular differences and displacements of the estimated from the true AC-PC lines. The automated detection of the AC-PC line in a PET study enables accurate stereotactic localization of functional signals without the need for additional anatomical imaging and provides a basis for objective and reproducible intersubject comparison.

Brain↗
PubMed1993

[A case of frontal lobe syndrome followed by serial 123I-IMP SPECT].

Single photon emission computed tomography (SPECT) studies with N-isopropyl-p-[123I]iodoamphetamine (IMP) were performed in a 58-year-old man with frontal lobe syndrome. He had abulia and personality changes suggesting frontal lobe impairment. Six follow-up SPECT studies were conducted during 18 months from the onset. On the first scan, no abnormal pattern of regional cerebral blood flow (rCBF) was found. On the second scan, a mild reduction of rCBF was observed in bilateral frontal lobes. Through the third to sixth scans, a progressed reduction of rCBF in bilateral frontal lobes was confirmed by a semi-quantitative regions-of-interest analysis. Contrarily, abulia was improved, and personality change was not progressed during that period. Magnetic resonance imaging on admission revealed only a small subdural hematoma and high intensity areas in the right frontal lobe, which were resolved at the time of the sixth SPECT scan. It is suggested that rCBF studies by SPECT is not necessary concordant with psychiatric symptoms, and has possible limitations in pathophysiological evaluation for psychiatric disorders.

Amphetamines↗
PubMed1992

cDNA cloning and chromosome assignment of the gene for human brain 14-3-3 protein eta chain.

We present the nucleotide sequence of a cDNA clone of mRNA encoding human 14-3-3 protein, a protein kinase-dependent activator of tyrosine and tryptophan hydroxylases and an endogenous inhibitor of protein kinase C. The 1,730-nucleotide sequence of the cloned cDNA contains 191 bp of a 5'-noncoding region, the complete 738 bp of coding region, and 801 bp of a 3'-noncoding region containing three canonical polyadenylation signals. The 14-3-3 protein eta chain cDNA encoded a polypeptide of 246 amino acids with a predicted molecular weight 28,196. The predicted amino acid sequence of human 14-3-3 protein eta was highly homologous to that of previously reported bovine and rat 14-3-3 proteins with only two amino acid differences. The sequence carries structural features as putative regions responsible for activation of tyrosine and tryptophan hydroxylases and for inhibition of Ca2+/phospholipid-dependent protein kinase C. Northern blot analysis demonstrated widespread expression of the 14-3-3 protein eta chain in cultured cell lines derived from various human tumors. These findings suggest the conservative functions of the 14-3-3 protein among species. Spot blot hybridization analysis with flow-sorted chromosomes showed that the human 14-3-3 protein eta chain gene is assigned to chromosome 22.

14-3-3 Proteins↗
PubMed1992

Methylation status of ribosomal RNA gene clusters in the flow-sorted human acrocentric chromosomes.

Southern blot analysis of the human acrocentric chromosomes that were flow-sorted from B-lymphoblastoid cell line GM130B revealed that the sensitivity of the ribosomal RNA (rDNA) gene clusters to the restriction enzyme NotI differs among these rDNA-containing chromosomes: the rDNA clusters of Chromosomes (Chr) 13, 14, and 15 are much more sensitive to NotI digestion than those of Chrs 21 and 22 in this particular cell line. Detailed analysis by use of methylation-sensitive enzymes HpaII and HhaI and methylation-insensitive enzyme MspI confirmed the significant variation in the methylation status of rDNA clusters among these chromosomes. Quantitative analysis by fluorescent in situ hybridization (FISH) indicated that copy number of rDNA varies among individual chromosomes, but the average copy number in the acrocentric Chrs 21 and 22 is significantly greater than that of the Chrs 13, 14, and 15 in GM130B cells. Similar analysis reveals that the methylation status of rDNA clusters in another B-lymphoblastoid cell line GM131 was different from that of GM130B. These data together indicate that the copy number and methylation patterns of rDNA clusters differ among individual acrocentric chromosomes in a given cell line, and they are different among cell lines.

Blotting, Southern↗
PubMed1992

Structure and expression of human and rat D2 dopamine receptor genes.

D2 dopamine receptor may be related with the pathogenesis of Parkinson's disease and schizophrenia. Furthermore, the antipsychotic drugs have high affinity for D2 dopamine receptor. We carried out the cloning of the genomic DNA for human D2 dopamine receptor and clarified the structure of this gene. Our isolated gene spans about 15 kbp and consists of seven exons interrupted by six introns. However, putative first exon was not yet identified. Spot blot hybridization analysis of cell sorter fractionated human chromosomal DNA with D2 receptor genomic DNA revealed the localization of this gene in the chromosome 11 fraction. We analyzed human genomic DNA by Southern blot hybridization with D2 dopamine receptor genomic DNA as a probe, but so far we could not find RFLP. Northern blot analyses of brain RNA of several animals and rat brain RNA after various treatments were carried out. Developmental changes of D2 dopamine receptor mRNA were observed in the rat brains.

Aging↗