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Biomedical subjects

S Ohno

Publications and source records attributed to S Ohno.

At least 865 records · Page 48Linked to original sources

Clinical observations on Behçet's disease in Tianjin, China.

Frequency and clinical manifestations of Behcet's disease were investigated in the Teaching Hospital of Tianjin Medical College, China. Diagnosis of Behcet's disease was made according to the diagnostic criteria proposed by the Japanese Research Committee on Behcet's disease. Forty-two patients, 14 men and 28 women, were found to have Behcet's disease. Fourteen patients belonged to the complete type and 28 to the incomplete type. Frequency of ocular lesions, especially in women patients, was lower and that of genital ulcers higher in China than those in Japan. Epidemiological and anthropological significance for the development of this disease was discussed.

Adolescent↗

Chromosomal translocations activating myc sequences and transduction of v-abl are critical events in the rapid induction of plasmacytomas by pristane and abelson virus.

Plasmacytomas with short latent periods can be induced in BALB/c mice by a single intraperitoneal (i.p.) injection of 0.5 ml pristane followed 20-40 d later by an injection of Abelson virus. The karyotypes of 18 such tumors were determined; 10 of these had rcpt 12;15, 5 had rcpt 6;15 and 3 had no translocations, but two of these have been shown to have interstitial deletions of chromosome 15. The specific breakpoints were the same as described in pristane-induced plasmacytomas, i.e., at 15D2 /3, 6C2 , and 12F2 . Near diploid karyotypes and trisomy of chromosome 11 were frequently seen. All of the Abelson-plus-pristane-induced plasmacytomas (ABPC) were studied as transplanted tumors, contained integrated v- abl sequences, and actively transcribed v- abl mRNA. All but one of these tumors contained abundant myc RNA transcripts. The shortness of the latent periods of the ABPC suggests that the rcpt 12;15 and rcpt 6;15 occur soon after pristane administration and are present at the time Abelson virus is introduced. In this form of plasmacytomagenesis , activated v- abl genes appear to bypass other genetic changes that require a much longer period of time in pristane plasmacytomagenesis . Nonetheless, the consistent finding of chromosome-15 alterations and abundant myc expression in these plasmacytomas emphasize the apparent need for multiple events even in the genesis of some tumors induced by rapid transforming viruses.

Abelson murine leukemia virus↗

Location of human T-cell leukemia virus (HTLV) p19 antigen on virus-producing cells.

Mouse monoclonal antibody to HTLV p19 was used to locate HTLV p19 on the surface of cells and virions by immunofluorescence microscopy (IFM) and immunoelectron microscopy (IEM). When HTLV-producing cells HUT 102 (B2 clone), MT-2 and strain A were used as target cells, HTLV p19 was detected on the surface of cells and virions as spots or small sectors by both IFM and IEM. Cells infected with animal type-C retroviruses, e.g., gibbon ape leukemia virus, simian sarcoma virus, feline leukemia virus, and Gross murine leukemia virus, were completely negative for HTLVp19 expression. Other human T cells not producing HTLV, including HUT78 and HSB2-0, immature or pre-T cells (Molt-3) derived from leukemia patients, and fresh peripheral blood T cells from healthy persons, were also negative. In addition, B cells including Rob-B, IM-9, Raji, and BT-1 did not react with the monoclonal antibody to HTLV p19. In the light of the presence of HTLV p19 in the periphery of acetone-fixed HTLV-producing cells as shown by IFM, it seems most likely that HTLV p19 is an internal antigen of HTLV with part of its structure protruding out of the viral and cell membrane. The monoclonal antibody to HTLV p19 did not lyse HTLV-producing cells in the presence of complement, as expected, because the antibody is an IgG1. Antibody-dependent cell-mediated cytotoxicity was also studied by the 51Cr-release assay. No cytotoxicity was observed. Although HTLV p19 does not contribute to the destruction of malignant T cells for treatment and/or virions for prophylaxis, this protein is an important marker for diagnosis of HTLV infection. The patterns of HTLV p19 expression described above were exactly the same for American HTLV-producing HUT 102 (B2 clone), for strain A cells and for Japanese HTLV-producing MT-2 cells. These results further substantiate the close relationship of the Japanese and American HTLV isolates.

Antibodies, Monoclonal↗

Ocular involvement by a peripheral T-cell lymphoma.

Non-Hodgkin's lymphomas can simulate uveitis. Two patients with non-Hodgkin's lymphoma had anterior uveitis. Material was obtained from the enucleated eye in case 1, and from an inguinal lymph node in case 2. Immunologic evaluation of this material led to the diagnosis of peripheral T-cell lymphoma in both cases. Immunologic evaluation is useful in the examination of patients with lymphoma.

Adult↗

Repeats of base oligomers as the primordial coding sequences of the primeval earth and their vestiges in modern genes.

Three outstanding properties uniquely qualify repeats of base oligomers as the primordial coding sequences of all polypeptide chains. First, when compared with randomly generated base sequences in general, they are more likely to have long open reading frames. Second, periodical polypeptide chains specified by such repeats are more likely to assume either alpha-helical or beta-sheet secondary structures than are polypeptide chains of random sequence. Third, provided that the number of bases in the oligomeric unit is not a multiple of 3, these internally repetitious coding sequences are impervious to randomly sustained base substitutions, deletions, and insertions. This is because the recurring periodicity of their polypeptide chains is given by three consecutive copies of the oligomeric unit translated in three different reading frames. Accordingly, when one reading frame is open, the other two are automatically open as well, all three being capable of coding for polypeptide chains of identical periodicity. Under this circumstance, a frame shift due to the deletion or insertion of a number of bases that is not a multiple of 3 fails to alter the down-stream amino acid sequence, and even a base change causing premature chain-termination can silence only one of the three potential coding units. Newly arisen coding sequences in modern organisms are oligomeric repeats, and most of the older genes retain various vestiges of their original internal repetitions. Some of the genes (e.g., oncogenes) have even inherited the property of being impervious to randomly sustained base changes.

Animals↗

Segmental homology and internal repetitiousness identified in putative nucleic acid polymerase and human hepatitis B surface antigen of human hepatitis B virus.

In a previous paper, it was argued that only those coding sequences descended from oligomeric repeats (the number of bases in the oligomeric unit not being a multiple of 3) can retain sufficiently long alternative open reading frames, and that such alternative open reading frames serve as the reservoir for the sudden generation of new polypeptide chains with novel functions. It was suggested that plasmid-encoded 6-amino hexanoic acid linear oligomer hydrolase that suddenly endowed Flavobacterium sp. K172 with the capacity to live off nylon by-products arose by the above mechanism. A corollary to the above argument is the expectation that those viral base sequences that are known to use two of the three alternative reading frames to encode two different polypeptide chains should invariably contain recognizable remains of the oligomeric tandem repeats, and as a consequence, various oligopeptidic repeats should also be present in the amino acid sequence of each. Furthermore, two polypeptide chains encoded by the same base sequence translated in different reading frames should show segmental homology of the type depicted previously. In the present paper, the base sequence of human hepatitis B virus ayw subtype that encodes an 832 amino acid residue long putative nucleic acid polymerase in one reading frame and a 226 residue long human hepatitis B surface antigen in the other reading frame was examined. All three predictions noted above were satisfied.

Amino Acid Sequence↗

Hemizygous interstitial deletion of chromosome 15 (band D) in three translocation-negative murine plasmacytomas.

Three murine plasmacytomas that were exceptional in lacking the characteristic (12;15) or (6;15) translocations were studied by G banding and high-resolution banding. One of every two chromosomes 15 (two of four in tetraploid tumors) was shortened in all three tumors. High-resolution banding analysis revealed that this was due to an interstitial deletion in the 15D band region. The two breaks responsible for the deletion have been tentatively localized to the interface of bands D2/3' and within band D2. One of the three plasmacytomas, ABPC45, had a rearranged c-myc gene. All three tumors contained a greater abundance of 2.4-kilobase myc RNA transcripts than normal spleen or thymus. The c-myc gene is located in the 15 D2/3 band region. We suggest that it may have joined the centromeric portion in the deletion plasmacytomas. This transposition may have led to its constitutive activation, as in the more frequent translocation-carrying plasmacytomas.

Animals↗

Birth of a unique enzyme from an alternative reading frame of the preexisted, internally repetitious coding sequence.

The mechanism of gene duplication as the means to acquire new genes with previously nonexistent functions is inherently self limiting in that the function possessed by a new protein, in reality, is but a mere variation of the preexisted theme. As the source of a truly unique protein, I suggest an unused open reading frame of the existing coding sequence. Only those coding sequences that started from oligomeric repeats are likely to retain alternative long open reading frames. Analysis of the published base sequence residing in the pOAD2 plasmid of Flavobacterium Sp. K172 indicated that the 392-amino acid-residue-long bacterial enzyme 6-aminohexanoic acid linear oligomer hydrolase involved in degradation of nylon oligomers is specified by an alternative open reading frame of the preexisted coding sequence that originally specified a 472-residue-long arginine-rich protein.

Amidohydrolases↗

Oligo-2',5'-adenylate synthetase activity in peripheral blood mononuclear leukocytes in various diseases.

Interferon induces oligo-2',5'-adenylate synthetase in cells. In various diseases, interferon was detectable in the circulation or was produced spontaneously from peripheral blood mononuclear leukocytes. The oligo-2',5'-adenylate synthetase activity in peripheral blood mononuclear leukocytes was examined in various diseases, including systemic lupus erythematosus, sarcoidosis, Vogt-Koyanagi-Harada disease, and Behcet's disease. The activity of this enzyme was significantly increased in systemic lupus erythematosus (P less than 0.01), sarcoidosis (P less than 0.01), and Vogt-Koyanagi-Harada disease (P less than 0.01) compared with that in controls, but the increase of activity was not significant in Behcet's disease (P greater than 0.05).

2',5'-Oligoadenylate Synthetase↗

Papuloerythroderma.

The main macroscopic features of 4 cases presented here are erythroderma-like lesions and solid papules. The former covers extensive areas over entire trunk and extremities, especially extensor surfaces. The latter is observed mainly on flexor surfaces of extremities and around the former. The axillae, inguinal regions, cubital and popliteal fossae, and big furrows on abdomen are spared from these lesions. Rashes appear first as papules and form erythroderma-like lesions through their assembly and confluence. Histologically, both show almost the same findings. Patients are older males with no general symptoms except itching. Although the course is chronic, lesions improve slowly and heal only after years.

Administration, Topical↗

Argon laser treatment of retinal neovascularization associated with sarcoidosis.

A 22-year-old Japanese woman with systemic sarcoidosis had retinal neovascularizations at seven loci with repeated vitreous hemorrhage in her right eye. Oral administration of prednisone was not effective. However, argon laser photocoagulation to the neovascularizations obliterated the neovascular fronds except at the optic nerve head; three months from the treatment, the neovascularization at the optic nerve head regressed spontaneously. No serious complications have occurred, and the vitreous hemorrhage has not recurred for the past two years. From these results, argon laser photocoagulation was thought to be effective for the treatment of retinal neovascularization in sarcoidosis.

Adult↗

Tumorigenicity of nasopharyngeal carcinoma hybrid cell line.

The spontaneous production of Epstein-Barr virus (EBV) and tumorigenicity in the BALB/c mutant nude mouse were studied with the use of the following 4 cell lines derived from the human nasopharynx: a) Ad-AH, an 8-azahypoxanthine-resistant epithelioid cell line; b) A2L, an EBV-carrying lymphoblastoid cell line; c) A2L/AH, an EBV-carrying epithelioid hybrid cell line established by fusion of Ad-AH cells with A2L cells; and d) NPC-KT, an EBV-carrying epithelioid hybrid cell line established by fusion of Ad-AH cells with nasopharyngeal carcinoma (NPC) primary culture cells. The NPC-KT hybrid cell line was the only cell line to produce EBV antigens of the lytic cycle and virus particles. Cloning efficiency in agarose was clearly related to tumorigenicity in nude mice. Especially high, frequent tumor formation was observed in the heterotransplantation of NPC-KT hybrid cells that presented poorly differentiated carcinoma, and the tumor cells were positive for EBV-associated nuclear antigen. These NPC-KT hybrid cells maintained the characteristics of a histologic type of NPC tumor cells. Thus experimental systems of NPC were established in vitro and in vivo by the application of NPC-KT hybrid cells to NPC model cells.

Animals↗

[Chromosome translocations and the activation of C-myc oncogene in mouse plasmacytomas].

Plasmacytomas can be induced in BALB/c mice by three different agents: (1) Mineral oil, (2) Solid plastics such as diffusion chambers, and (3) Abelson murine leukemia virus plus pristane. We examined chromosome aberrations in mouse plasmacytomas induced by each of the three agents. Most of plasmacytomas showed the specific translocations of chromosomes between either No. 12 and No. 15 or No. 6 and No. 15. These chromosome translocations were common to all plasmacytomas induced by different agents. The specific breakpoints were at 12F2 where IgH genes appear to locate, and 6C2 where kappa light chain genes might be located, and 15D2/3 where c-myc oncogene appears to locate. However, we have found very recently a few plasmacytomas which have no translocations of chromosomes. The subregion (s) of one copy of chromosome 15 which is called D1:D2 appears to be deleted in these plasmacytomas. In the next study, we examined the relationship of chromosomal aberrations to the activation of c-myc oncogene. Not only the plasmacytomas with chromosome translocations, but also the translocation-negative plasmacytomas showed the either rearrangement or germline type of c-myc DNA. Rearranged c-myc transcript was found only in plasmacytomas with the 12;15 translocation. However, not all plasmacytomas belonging to this group expressed the altered c-myc RNA transcript. Our experiments indicated that the germline type c-myc RNA was 2.4 kb and the rearranged c-myc RNA was mostly 1.8 kb in length. Concerning the c-myc DNA, the germline type was 21 kb and the rearranged type of c-myc DNA was estimated, mostly, to be 14 kb by EcoRI digestion.

Animals↗