The tendency toward English-language papers in MEDLINE.
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Authorship↗
Biomedical subjects
S Yamazaki
Publications and source records attributed to S Yamazaki.
Nucleotide sequence of the genes, encoding the pentaheme cytochrome (dmsC) and the transmembrane protein (dmsB), involved in dimethyl sulfoxide respiration from Rhodobacter sphaeroides f. sp. denitrificans.
The nucleotide sequence of the genes encoding a pentaheme cytochrome (dmsC) and a transmembrane protein (dmsB) were determined upstream of the dmsA gene encoding dimethyl sulfoxide reductase from Rhodobacter sphaeroides f. sp. denitrificans. dmsC and dmsB encode proteins of 404 and 226 amino acid residues, which show 40% and 26% identity to the pentaheme cytochrome TorC and the transmembrane protein TorD, respectively, of the trimethylamine N-oxide reduction system in Escherichia coli.
Amino Acid Sequence↗
Genetic and phylogenetic analysis of HIV type 1 env subtypes in Ghana, west Africa.
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Adolescent↗
Acceptance of primary skin graft after treatment with anti-intercellular adhesion molecule-1 and anti-leukocyte function-associated antigen-1 monoclonal antibodies in mice.
Although a short-term blockade of intercellular adhesion molecule-1 (ICAM-1) and leukocyte function-associated antigen-1 (LFA-1) adhesion allows induction of specific tolerance to solid organs, their effect on primary skin allografts is not yet known. Effects of anti-ICAM-1 and anti-LFA-1 monoclonal antibodies (mAb) on primary skin allograft survival were investigated. Recipient mice were treated with either a combination of anti-ICAM-1 and anti-LFA-1 mAbs or a control mAb for the first 22 days. The survival of BALB/c skin in the C3H/He recipient was not prolonged. Subsequently, MHC class I (bm1)- or class II (bm12)-disparate skin grafts were transplanted into C57BL/6 mice. Remarkable prolongation was observed in these combinations. Four of 10 bm12 grafts and 4 of 9 bm1 grafts were accepted for more than 120 days. These results suggest that mouse strain combination is an important factor for skin graft acceptance. We suggest that unique immunogenicity and a lack of vascularization of skin allografts account for the weak immunosuppression produced by anti-adhesion molecule mAbs.
Animals↗
Adenomyoepithelioma of the Breast: A Case Reprot and a Review of Literature.
A 74-year-old woman complained of a small nodule in the outer lower quadrant of her left breast. On physical examination, a 0.9 x 0.8 cm, round-shaped and firmly elastic nodule was palpated. Excisional biopsy was performed. Histologically, the tumor was separated into, with a bicellular pattern, containing both numerous glandular structures and numerous spindle-shaped cells. Immunohistochemical staining for EMA and cytokeratin showed strongly positive immunoreactivity for epithelial cells. Staining for &aipha;-SMA showed strongly positive immunoreactivity for myoepithelial components. Staining for keratin and S-100 protein showed weakly positive immunoreactivity for myoepithelial cells. Microscopically, the tumor was diagnosed as adenomyoepithelioma of the breast. Immunohistochemical examination is needed to distinguish epithelial cell proliferation from myoepithelial cell proliferation. Immunohistochemical examination using antibodies against EMA, alpha-SMA, Keratin, cytokeratin and S-100 protein, is indispensable.
Journal Article↗
Reverse transcription-polymerase chain reaction detection and sequence analysis of small round-structured viruses in Japan.
Between 1985 and 1995, mass outbreaks of acute gastroenteritis caused by small round-structured virus (SRSV), occurred in eight prefectures in Japan. Fecal samples from 59 patients ill during these outbreaks were recently examined in our laboratory by electron microscopy (EM) and by reverse transcription-polymerase chain reaction (RT-PCR). For RT-PCR, we prepared two sets of primers, a set corresponding to the polymerase region of open reading frame 1 (ORF-1) and a set corresponding to the capsid region of ORF-2 of Norwalk virus (NV). The SRSV nucleic acid detection rate with these primers was more than double that achieved with EM. Most samples found by EM to contain virus particles were also positive by PCR. When the two sets of primers were used separately, the virus detection rate differed depending on the primer used, suggesting that the viral strains examined were not genetically not homogeneous. We then selected nine strains of the virus, cloned their PCR products and analyzed their base sequences. The base sequences of these strains were compared with those of reference strains including prototype NV and Snow Mountain agent (SMA). This comparison yielded the following findings: (1) SRSVs that cause mass outbreaks of gastroenteritis in Japan are genetically variable; (2) SRSV strains that are genetically similar to SMA and SRSV-OTH 25/89/J(OTH25) are dominant in Japan, but strains similar to NV are also present in this country; and (3) a strain (MI1/94) which is genetically identical to Southampton virus (SHV) was detected. Detection of SRSV using sensitive RT-PCR and analysis of the sequences of the amplification products seems to provide a useful means of studying the molecular epidemiology of SRSV.
Adult↗
Uptake of radioactive octanoate in astrocytoma cells: basic studies for application of [11C]octanoate as a PET tracer.
Fatty acids are taken up and metabolized in the brain. In vitro uptake experiments on astrocytoma cells were carried out to assess the potential use of [1-11C]octanoate as a positron emission tomography (PET) tracer for astroglial functions. Uptake of [1-14C]octanoate increased in a time-dependent fashion until 60 min after application. The uptake of [1-11C]octanoate showed similar results to that of [1-14C]octanoate until 10 min. As for medium pH, [1-14C]octanoate uptake increased gradually with the decrease in pH. We also examined the effects of glutamate, glucose deprivation and hypoxia on the uptake of octanoate and found that these conditions did not bring about any change in the extent of [1-14C]octanoate uptake. These results show that the octanoate uptake was not influenced by any of several pathological conditions. When the number of astrocytes increases in the area of hypoglycemia or hypoxia near a brain lesion, the amount of octanoate uptake also increases, so this indicates the possibility that 11C-octanoate will detect a brain lesion.
Astrocytoma↗
Production of chemotactic factor(s) of Langerhans cells by lymph node cells in contact sensitivity.
Langerhans cells (LCs) have to leave the epidermis to migrate into the regional lymph node (LN) after receiving immunogenic signals in contact sensitivity. There should be some molecules responsible for migration of LC in this process. In order to determine whether LN cells can generate such regulatory molecules, we made a search of such molecules in the culture supernatant of LN cells obtained from hapten-painted mice by using a modified Boyden chamber method. The molecule of LC chemotaxis appeared in the culture supernatant at 24 h after hapten painting and its production declined with time thereafter. Antibodies against both ICAM-1 and LFA-1 partially inhibited the chemotactic activity, but this was not the case with anti-TNF-alpha antibody, anti-GM-CSF antibody, fibronectin RGDS. RGES peptide or laminin. The molecule was heat labile and appeared as a molecule of 45-68 kDa on high performance liquid chromatography. Our results suggest that LN cells generate one of the chemotactic molecules of LCs, by which LC can migrate to the regional LN in contact sensitivity.
Animals↗
[1-11C]octanoate as a potential PET tracer for studying glial functions: PET evaluation in rats and cats.
To evaluate the ability of [1-11C]octanoate as a PET tracer for imaging the brain, we examined its distribution in the brain and surrounding tissues in rats and cats with PET. In rats, owing to the accumulated radioactivity in the harderian glands, clear brain images were not obtained at rostral levels. In cats, the brain was imaged clearly at every level of the coronal brain slices, suggesting the potential of [1-11C]octanoate for imaging the brain.
Animals↗
Derivation of T-cell receptor alpha-chain double expresser lines from normal murine mature T cells.
Because the T-cell receptor (TCR) alpha-chain locus is known to lack allelic exclusion of rearrangements, and as a recent report revealed the existence of alpha-chain double expressers among normal human peripheral blood lymphocytes (PBL), the possible existence of TCR alpha-chain double expressers among mature murine T cells was examined. Although two-colour staining analysis of normal T-cell populations did not immediately reveal recognizable clusters of V alpha double expressers, alternative in vitro stimulations of normal murine T cells with antibodies to two different TCR V alpha chains reproducibly induced TCR alpha-chain double-expresser lines. TCR complexes with different alpha-chains on such T cells were both shown to be functional. The cell lines were heterogeneous with respect to V beta usage and the ratio of the expressed amounts of the two alpha-chains on the surface. The ratio of the two expressed alpha-chains was found to be very stable over a long period of time. These results are consistent with the earlier report on alpha-chain double expressers among human T cells and also show normal occurrence of TCR alpha-chain double expressers in murine T-cell populations.
Animals↗
Cutaneous myiasis due to Dermatobia hominis in Japan.
A 29-year-old man with a furuncle-like lesion brought in a maggot on the next day after his first visit to our clinic. He said it moved out from the eruption spontaneously. He had previously visited Parana and Sao Paulo in Brazil before he noticed the symptom. The maggot was confirmed to be a third instar larva of Dermatobia hominis. Japanese cases of cutaneous myiasis are reviewed.
Adolescent↗
No proof of HTLV-I/II in intravenous drug abusers with a high rate of HIV-1 infection in central Thailand.
Serum specimens of 1,074 intravenous drug abusers (IVDA) were examined for infection with HIV-1, HTLV-I and HTLV-II in central Thailand. Three hundred and sixty-two of the specimens were seropositive for HIV-1 (33.7%). The HIV-1 seropositive IVDAs exhibited increased seropositivity with age through group 40-44 and significantly decreased seropositivity over the age of 45. In contrast, no seropositivity to either HTLV-I or -II was detected in the samples tested by a particle-agglutination assay for HTLV followed by type-specific Western blotting for HTLV. Reference to previous reports suggested that the rate of HIV infection in IVDAs has decreased with no HTLV-I or HTLV-II in Thailand when compared with that of the HIV infection in 1992.
Adolescent↗
Isolation and characterization of mumps virus strains in a mumps outbreak with a high incidence of aseptic meningitis.
In 1993, mumps with a high incidence of aseptic meningitis became prevalent in Akita prefecture, Japan. Three mumps virus isolates obtained from the nonvaccine-associated cases lacked the BamHI restriction cleavage site of the P gene, like the Urabe strain (Yamada, A. et al, Vaccine 8: 553-557). However, four additional nucleotide substitutions were found in the determined region of 157 bp. Fourteen of 19 cases from which mumps virus showing the Urabe-like RFLP profile was detected were complicated with symptomatic meningitis, whereas there were only four cases of meningitis among 23 individuals infected with the wild type showing no Urabe-like RFLP profile (non-"Urabe-like" wild-type). The incidence of meningitis was over 70% among patients infected with the "Urabe-like" wild-type virus. The "Urabe-like" wild-type. disappeared after February 1994 in the epidemic area and was replaced by the non-"Urabe-like" wild-type. Patients infected with the "Urabe-like" wild-type lived in a closed colony, in which there were two instances of transmission between siblings. Thus this outbreak was transient and narrowly localized.
Base Sequence↗
Human T-lymphotropic virus type II in Japan.
Serum specimens were assayed for human T-lymphotropic virus type II(HTLV-II) infection in 1,500 individuals known to be seropositive for HTLV-I and 30,000 blood donors in Japan. All HTLV-I-positive individuals were negative for HTLV-II. However, one of the blood donors was clearly seropositive for HTLV-II. Further, the donor was shown to be positive for HTLV-IIb. Here we report at least one case with HTLV-II in Japan and discuss the origin of the infection.
Adult↗
Presence in Pieris rapae of cytotoxic activity against human carcinoma cells.
Cytotoxic activity in extracts of pupae and adults of various kinds of butterflies and moths was tested in vitro against the human gastric carcinoma cell line, TMK-1, which was chosen as an example of human carcinoma cells. Among the species examined, cytotoxicity was limited to Pieris rapae, Pieris napi and Pieris brassicae. Activity was found down to a dilution of 1/10(4), while with the other butterflies and moths no activity was observed, even at 1/10(2). When the cytotoxicity of the three developmental stages, larvae, pupae and adults, of Pieris rapae was compared, the pupae showed the strongest activity, the IC50 against TMK-1 cells being at the 1/10(6) dilution. For larvae and adults, the respective IC50 values were at the 1/10(5) and 5/10(5) dilutions. The active principle in the pupae of Pieris rapae was found to be heat-labile and not extractable with organic solvents, but precipitated with ammonium sulfate and digested by proteases, suggesting that it is a protein. This cytotoxic factor was named pierisin.
Animals↗
Hair abnormality of Fabry disease.
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Adult↗
Electron-microscopic study of sclerodermatous chronic graft-versus-host disease.
BACKGROUND: Sclerodermatous chronic graft-versus-host disease (SC-GVHD) resembles systemic scleroderma (SSD) closely, both clinically and histologically. Our purpose was to try to define the morphologic differences of collagen fibers between SC-GVHD and SSD. MATERIALS AND METHODS: Using electron microscopy, we compared the morphology of collagen fibers in a 15-year old girl with SC-GVHD with those of three patients with SSD. RESULTS: In SC-GVHD, sclerosis is located in the superficial dermis and collagen fibers of irregular diameter are seen in the subepidermal area. In SSD, sclerosis is seen in the lower dermis and subcutaneous fatty tissue, and collagen fibers of irregular diameter are located in the deep dermis. Some of the collagen fibers were degenerative in the superficial dermis in SC-GVHD. We observed low-density, round structures in cross sections of collagen fibers. CONCLUSIONS: The difference in initial location and morphologic appearance of collagen fibers may indicate a different pathogenesis in SC-GVHD compared to SSD.
Adolescent↗
Double-lined linear scleroderma.
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Adult↗