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Biomedical subjects

S Nagata

Publications and source records attributed to S Nagata.

At least 631 records · Page 35Linked to original sources
PubMed1987

[Optimum time for surgical intervention in pure mitral regurgitation: serial echocardiographic evaluations].

To determine the optimum time for surgical intervention in pure mitral regurgitation, 39 patients were studied by echocardiography before and after surgery. Pure mitral regurgitation included mitral valve prolapse with or without ruptured chordae tendineae. Twenty-two patients had mitral valve replacement and 17 had mitral valve reconstruction. Serial echocardiograms were obtained from all 39 patients (average follow-up: 40 months). Two of the 39 patients died suddenly at home on 26 and 62 months after surgery. One of the 39 patients now suffers from congestive heart failure. These three patients had preoperative left ventricular end-diastolic dimensions greater than 70 mm and left ventricular end-systolic dimension greater than 50 mm. Operation is recommended for patients with end-diastolic dimension less than 70 mm and end-systolic dimension less than 50 mm.

Echocardiography↗
PubMed1987

[Relationship of two-dimensional echocardiographic mitral valve prolapse to mitral regurgitation assessed by color Doppler flow imaging].

Although two-dimensional echocardiography is a standard for diagnosing mitral valve prolapse, the diagnostic criteria are controversial. Regardless of valve ballooning we have used our criteria which are based on the dislocation of the mitral valve coaptation. The purpose of this study was to clarify the relationship between the location and the degree of mitral valve prolapse assessed by two-dimensional echocardiography and those of mitral regurgitation evaluated by color Doppler flow imaging, which enables us detailed analysis of regurgitation. Twenty-three patients with idiopathic mitral valve prolapse diagnosed by our criteria were studied. They were 14 men and nine women, ranging in age from 19 to 72 years (mean 44.7). In any patients, prolapse of either the anterior or posterior leaflet does not satisfy the Gilbert's criteria. Twenty of the 23 patients had mitral regurgitation by color Doppler flow imaging, and the grade was II, III or IV in 16 of these 20 patients. In 19 of 20 patients, the localization of the regurgitant jet flow from the mitral orifice coincided with the two-dimensional echocardiographic site of dislocation of mitral valve coaptation. Therefore, it was concluded that the dislocation of mitral leaflet coaptation detected by two-dimensional echocardiography is an abnormal finding regardless of the protrusion of the valve beyond the mitral ring.

Adult↗
PubMed1987

[Papillary muscle infarction: echocardiographic features and genetic factors].

To study the pathogenesis of papillary muscle infarction, its echocardiographic features were examined in 60 patients with old inferior infarction. Sixty-three healthy elderly persons served as the controls. 1. The papillary muscles were echocardiographically classified as fingerlike and non-fingerlike in configuration whose frequencies were 43% and 57%, respectively. In healthy subjects, the papillary muscles were less echogenic than the left ventricular wall. 2. In five patients, the posteromedial papillary muscle exhibited enhanced echo intensity and no contraction. The papillary muscles in two of these five patients were histologically examined and the diagnosis of papillary muscle infarction was verified. In these five patients, the papillary muscles were echocardiographically classified as fingerlike, and left ventricular infarction was observed to involve the attachment of the posteromedial papillary muscle. All five patients had mitral valve prolapse; posterior in four and anterior in one. Inferior infarction extended to the region just beneath the mitral annulus in the former four patients, but not in the latter one. 3. The echocardiographic features of papillary muscle infarction consisted of enhanced echo intensity of the papillary muscle and mitral valve prolapse, especially that of the posterior leaflet at the posteromedial commissural side, and extension of the asynergy region to the attachment portion of the papillary muscle. The fingerlike morphology of the papillary muscle and involvement of the attachment within the infarcted region are predispositions to the development of papillary muscle infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

The vestibulothalamic connections in the rat: a morphological analysis using wheat germ agglutinin-horseradish peroxidase.

The vestibulothalamic connections were studied in the rat using wheat germ agglutinin-horseradish peroxidase (WGA-HRP). The distributions of anterograde labelling of fibers and terminals in the brainstem and the thalamus were analyzed by injecting WGA-HRP into the superior (SVN) and lateral (LVN) vestibular nuclei, and the medial (MVN) and inferior (IVN) vestibular nuclei. The distributions of retrograde labelling of cells were analyzed in the vestibular nuclear complex by injecting WGA-HRP into the thalamus centered in the central lateral nucleus (CL), ventral posterolateral nucleus (VPL), and rostral part of the dorsal medial geniculate nucleus (rMGd). The vestibular projection to the CL via the medial longitudinal fasciculus (MLF) and the ascending tract of Deiters (ATD) originates mainly in the contralateral MVN and ipsilateral SVN. The vestibular projections to the VPL and the ventral lateral nucleus (VL) via MLF, ATD and superior cerebellar peduncle (SCP) originate mainly in the MVN and SVN, bilaterally. The projection to the rMGd via the lateral lemniscus-inferior collicular brachium, and MLF (and SCP) originates in the contralateral IVN.

Animals↗
PubMed1986

Undermethylation of interferon-gamma gene in human T cell lines and normal T lymphocytes.

The relative levels of DNA methylation at CCGG sequences within and around the interferon-gamma (IFN-gamma) gene in normal human tissues and cell lines were examined by Southern blot analysis using isoschizomeric restriction enzymes, HpaII and MspI. On the test of normal tissues, the IFN-gamma gene was undermethylated only in a small population of T lymphocyte, whereas the gene was fully methylated in T cell-depleted lymphocytes and uterus cells. In TCL-Fuj cell line which is a T cell line producing a high level of IFN-gamma spontaneously, the IFN-gamma gene was undermethylated. Moreover, the extent of DNA methylation was inversely correlated to the level of expression of the IFN-gamma gene in several T cell lines including sublines derived from TCL-Fuj cells. However, partial or complete unmethylation at the CCGG sites of IFN-gamma gene was observed in a promyelocytic leukemia cell line and two epithelial cell lines that fail to produce IFN-gamma irrespective of induction. These results suggest that undermethylation of IFN-gamma gene is necessary but not sufficient for its efficient expression.

Cell Line↗
PubMed1986

The chromosomal gene structure and two mRNAs for human granulocyte colony-stimulating factor.

Two different cDNAs for human granulocyte colony-stimulating factor (G-CSF) were isolated from a cDNA library constructed with mRNA prepared from human squamous carcinoma cells, which produce G-CSF constitutively. The nucleotide sequence analysis of both cDNAs indicated that two polypeptides coded by these cDNAs are different at one position where three amino acids are deleted/inserted. When the two cDNAs were introduced into monkey COS cells under the SV40 early promoter, both of them produced proteins having authentic G-CSF activity and some difference in the specific activity was suggested. A human gene library was then screened with the G-CSF cDNA and the DNA fragment containing the G-CSF chromosomal gene was characterized by the nucleotide sequence analysis. The human G-CSF gene is interrupted by four introns and a comparison of the structures of the two G-CSF cDNAs with that of the chromosomal gene indicated that the two mRNAs are generated by alternative use of two 5' splice donor sequences in the second intron of the G-CSF gene. When the G-CSF chromosomal gene was expressed in monkey COS cells by using the SV40 enhancer two mRNAs were detected by S1 mapping analysis.

Amino Acid Sequence↗
PubMed1986

Accordion flap.

The accordion flap is proposed as a means of covering a rhombic defect. A prominent feature of the method presented is in the preparation of a flap on one side of the skin defect, resulting in little dog ear.

Adult↗
PubMed1986

The Z in Z-plasty must have a long trunk.

Erroneous thinking in regard to Z-plasty, which is a fundamental technique in plastic surgery, has been pointed out. In most cases of Z-plasty, the trunk of the Z should be designed longer than the two limbs.

Adolescent↗
PubMed1986

Chondrosarcoma arising from the falx cerebri.

A chondrosarcoma arising from the falx cerebri in a 15-year-old boy is reported. The patient had been suffering from convulsive seizures and weakness of the limbs on the left side for about 7 months prior to admission. A high-density mass attached to the falx was demonstrated by computed tomographic scan. Clinically it was very similar to a falx meningioma, and the final diagnosis was obtained from histopathological examination. The tumor was completely excised at operation, which is extremely important to prevent both local recurrence and distant metastasis.

Adolescent↗
PubMed1986

Structure of the two genes coding for polypeptide chain elongation factor 1 alpha (EF-1 alpha) from Saccharomyces cerevisiae.

Polypeptide chain elongation factor 1 alpha (EF-1 alpha) of Saccharomyces cerevisiae is encoded by two distinct genes designated EF1 alpha A and EF1 alpha B [Nagata et al., EMBO J. 3 (1984) 1825-1830]. Both genes were cloned, and their nucleotide (nt) sequences were determined [see also Schirmaier and Philippsen, EMBO J. 3 (1984) 3311-3315, and Cottrelle et al., J. Biol. Chem. 260 (1985) 3090-3096]. They contain an open reading frame of 1374 nt coding for an identical protein of 458 amino acid residues, although their nt sequences differed at two positions. In this paper, we determined their 5'- and 3'-flanking sequences which were considerably different each other. From the S1 nuclease mapping of mRNA, both genes are found to be expressed almost to the same extent in exponentially growing cells. The transcription start points for EF1 alpha A and EF1 alpha B mRNAs were precisely located by primer extension procedure at 32 and 23 nt upstream of the start codons, respectively. The sequence which commonly exists in the 5'-flanking regions of ribosomal protein genes of S. cerevisiae was also present in the two EF1 alpha genes.

Amino Acid Sequence↗
PubMed1986

Molecular cloning and sequence determination of cDNAs for alpha subunits of the guanine nucleotide-binding proteins Gs, Gi, and Go from rat brain.

We have cloned cDNAs encoding alpha subunits of the guanine nucleotide-binding proteins Gs, Gi, and Go and determined their nucleotide sequences. Purified preparations of Gi and Go alpha subunits (Gi alpha and Go alpha) from rat brain were completely digested with trypsin, and peptides were subjected to amino acid sequence analysis. By screening of a cDNA library from rat C6 glioma cells with a synthetic probe corresponding to a 17 amino acid sequence, a clone encoding the sequence of Go alpha was obtained. Then, the library was rescreened with a Go alpha cDNA probe to isolate several strongly or weakly hybridizing clones. cDNAs encoding the complete sequences of Gi alpha and Gs alpha were thus obtained. From nucleotide sequence analysis, the amino acid sequences of Gs alpha and Gi alpha were deduced; they contain 394 and 355 amino acid residues (including the initiator methionine), respectively. The calculated molecular weights for Gs alpha and Gi alpha were 45,663 and 40,499, respectively. The Go alpha clone encoded a sequence of 310 amino acid residues that lacked the NH2 terminus. The homology of the alpha subunits of Gs, Gi, Go, transducin, and ras-encoded protein is discussed.

Animals↗
PubMed1986

Isolation and characterization of the cDNA for murine granulocyte colony-stimulating factor.

A cDNA sequence coding for murine granulocyte colony-stimulating factor (G-CSF) has been isolated from a cDNA library prepared with mRNA derived from murine fibrosarcoma NFSA cells, which produce G-CSF constitutively. Identification of murine G-CSF cDNA was based on the cross-hybridization with human G-CSF cDNA under a low-stringency condition. The cDNA can encode a polypeptide consisting of a 30-amino acid signal sequence, followed by a mature G-CSF sequence of 178 amino acids with a calculated Mr of 19,061. The nucleotide sequence and the deduced amino acid sequence of murine G-CSF cDNA were 69.3% and 72.6% homologous, respectively, to the corresponding sequences of human G-CSF cDNA. The murine G-CSF cDNA, when introduced into monkey COS cells under the simian virus 40 promoter, could direct the synthesis of a protein that can stimulate the granulocyte colony formation from mouse bone marrow cells and support the proliferation of murine NFS-60 myeloid leukemia cells.

Amino Acid Sequence↗
PubMed1986

Reconstruction of the columella with bilateral nasolabial flaps.

Nasolabial flaps are beneficial in the reconstruction of total defects of the columella. Two nasolabial flaps were used in a one-stage reconstruction of the columella. Both flaps were simultaneously transposed as subcutaneous pedicle flaps and set up in a sandwich shape. We could reconstruct a well-shaped and balanced columella.

Humans↗
PubMed1986

Primary osteoma cutis of the back.

A case of primary osteoma cutis on the back is reported. This case showed an unusual form of calcification on soft x-ray. Histologic examination disclosed mature bone in the subcutis. There was no history or evidence of any skin disease prior to the development of the osteoma. The literature is reviewed and discussed.

Back↗
PubMed1986

Two monoclonal antibodies distinguish between human recombinant interferon-alpha 5s produced by Escherichia coli and by mouse cells.

Two monoclonal antibodies against human IFN-alpha--one against natural leukocyte IFN-alpha and the other against recombinant human IFN-alpha 2 produced in E. coli--were prepared, and designated as HT-1, and 104-5-f, respectively. These monoclonal antibodies were used to examine the antigenicities of recombinant human IFN-alpha 5s produced by E. coli and by mouse cells. The HT-1 antibody could bind and neutralize recombinant human IFN-alpha 5 synthesized in mouse cells, but not recombinant human IFN-alpha 5 synthesized in E. coli. On the other hand, the 104-5-f antibody could bind and neutralize recombinant human IFN-alpha 5 synthesized in E. coli but not recombinant human IFN-alpha 5 synthesized in mouse cells. Then these monoclonal antibodies or sheep polyclonal antibody against human IFN-alpha were used to immunoprecipitate the radioactively labeled recombinant human IFN-alpha 5 synthesized either in E. coli or mouse cells, and analysed on polyacrylamide gel electrophoresis in the presence of NaDodSO4. The labeled recombinant human IFN-alpha 5 produced by mouse cells could be immunoprecipitated with the HT-1 monoclonal antibody or sheep anti-(human IFN-alpha) polyclonal antibody but not with the 104-5-f monoclonal antibody and showed a band of Mr. 17,500 on polyacrylamide gel electrophoresis in the presence of NaDodSO4. On the other hand, the labeled recombinant human IFN-alpha 5 produced by E. coli could be immunoprecipitated with the 104-5-f monoclonal antibody but not with the HT-1 monoclonal antibody and showed a band of similar Mr. on polyacrylamide gel electrophoresis.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗