PubMed Health⌕ Search

Biomedical subjects

A Ochi

Publications and source records attributed to A Ochi.

71 records · Page 4Linked to original sources
PubMed1987

[Siblings of familial adenomatosis coli with gastric cancer--case report].

Adenomatosis coli is recently regarded as a systemic disease with a predisposition to multiple tumor formation. We report siblings of familial adenomatosis coli with gastric cancers. Case 1 was a 58 year-old elder brother. His diagnosis was familial adenomatosis coli accompanied with colon cancer and simultaneous early gastric cancer. Total colectomy and partial gastrectomy were carried out on Mar. 13, 1984 at our hospital. Numerous polyps over the whole colon and an ulcerative tumor in the hepatic flexure were found in the resected colon. Histologically tubular adenocarcinoma were demonstrated in the ulcerative tumor, and all other polyps were adenomas. In the resected gastric specimen, there were two shallow, depressed lesions on the each anterior and posterior wall of the antrum. Histologically both of them were adenocarcinoma confined within the mucosa. Postoperative course was satisfactory and he is quite healthy 2 and a half years after surgery. Case 2 was a 56 year-old younger brother. He received a partial gastrectomy for advanced gastric cancer at another hospital on May 20, 1982. In one and a half year from the surgery, a large lung tumor (probably metastasis of the gastric cancer) was found and he received chemotherapy. He also received radiation therapy in June, 1984 and during this admission barium enema study was performed. It revealed numerous polyps over the whole colon. No cancerous lesions were found. He died of lung tumor on Dec. 8, 1985. The similar siblings were first reported by Kokaji et al. in 1984, and our cases seem to be the second ones.

Adenocarcinoma↗
PubMed1986

Functional reconstitution of class II major histocompatibility complex molecules, I-A alpha k and I-A beta k.

Genomic DNA fragments carrying the genes, I-A alpha k and I-A beta k, encoding the class II major histocompatibility complex (MHC) molecule I-Ak were inserted into a transducing vector pRSVneo. This vector was introduced into a B lymphoma line expressing the class II molecules (H-2d). The resultant transformants expressed I-Ak molecules on the membrane surface. These transformants were capable of presenting antigen to I-Ak restricted helper T (Th) cells and were susceptible to lysis by class II specific killer T cells. The vector pR-A alpha kA beta k which contains both I-A alpha k and I-A beta k genes will provide a useful tool to analyze function of Ia molecules in cellular interaction, recognition, regulations and stimulation.

Animals↗
PubMed1986

Enhanced transcription in a pre-B-like cell line transformed with cloned antibody genes after antigen-specific stimulation.

The transducing vector, pSV2-neo, carrying the rearranged immunoglobulin (Ig) heavy (mu) and light (kappa) chain genes specific for the hapten 2,4,6-trinitrophenyl (TNP) was introduced into a pre-B cell line. The transformants expressed the TNP-specific IgM receptor on the surface. Furthermore, the addition of TNP-bovine serum albumin (hapten-carrier conjugate) to the culture media activated the expression of the transferred Ig genes and several endogenous genes such as v-abl and beta-tubulin. However, expression of the beta2-microglobulin gene was not affected. The results presented in this paper show that transfection of cloned Ig genes into B cells is a useful system for establishing monoclonal B cell lines expressing functional Ig receptor molecules with defined hapten specificity.

Animals↗
PubMed1986

Immunoglobulin synthesis in non-B cell lines.

A recombinant vector carrying rearranged immunoglobulin heavy (mu) and light (kappa) chain genes was introduced into several cell lines of non-B lineage including T cell (EL4) and two fibroblast lines (CV-1 and L cells). Our results indicated that intracytoplasmic mu-chains, both secretory and membrane types, were expressed in the recipient cell lines. Small amounts of kappa-chain transcripts, corresponding in size to authentic kappa-chain mRNA, were detected in EL4 and L cell transformants, whereas CV-1 transformants did not express the authentic kappa-chain RNA. EL4 and L cell transformants produced kappa-chain. This system will be quite useful for the analysis of regulatory mechanisms involved in immunoglobulin synthesis in non-B cells.

Animals↗
PubMed1986

Antigen presentation by a B-cell line transfected with cloned immunoglobulin heavy- and light-chain genes specific for a defined hapten.

The rearranged genes encoding immunoglobulin heavy (mu) and light (kappa) chains specific for the hapten 2,4,6-trinitrophenyl (Tnp) were introduced into a B-lymphoma line that bears surface IgG with an unknown specificity and expresses surface Ia molecules. A transformant expressing surface IgM specific for Tnp was obtained. The transformant was found to present Tnp-proteins to antigen (protein)-specific T cells far more efficiently than the parenteral B-lymphoma line. This artificial system, utilizing recombinant DNA technology and gene transfer, provides several approaches for the study of T-cell-B-cell interactions.

Animals↗
PubMed1986

[Saccular aneurysm arising from the basilar artery fenestration: a case report].

This patient, 29-year-old female, had an attack of subarachnoid hemorrhage. On admission a cerebral angiogram showed a saccular aneurysm arising from the proximal origin of the fenestrated basilar artery (Fig. 1). The aneurysm was clipped successfully with two steps under a right retromastoidal suboccipital craniectomy (Fig. 2). Association of the fenestrated basilar artery and saccular aneurysm is rare. To our knowledge, 9 cases have been found in the literature and only 4 cases were operated. The authors discussed the pathogenesis and treatment of such aneurysms.

Adult↗
PubMed1984

Biochemical genetics of the mouse IgM system.

Using a mouse hybridoma system, we have developed methods of isolating a variety of mutant cell lines in which immunoglobulin function or synthesis is defective. The analysis of mutants defective in kappa chain synthesis has defined a class of murine transposons. The deletion mutants produce immunoglobulin M (IgM) bearing mu heavy chain fragments and provide information on the requirements of IgM assembly and mu gene expression. We also describe a transfer system for the mu and kappa genes which will be useful in analyzing the structural basis of IgM function.

Animals↗
PubMed1983

Presence of IgT-C and I-A subregion-encoded determinants on distinct chains of monoclonal antigen-specific augmenting factor derived from a T cell hybridoma.

Monoclonal antibodies specific for mouse T cell alloantigens, Tindd and Tsud, linked to the Igh-1 locus on chromosome 12, were used to directly define the antigen-binding molecule produced by a cloned hybridoma. The T cell hybridoma, FL10, was established from antigen-binding T cells of A/J mice. FL10 produces an antigen-specific augmenting T cell factor (TaF) that bears a unique I region-controlled determinant (I-A) and has antigen-binding capacity. The Tindd, but not the Tsud, determinant was detected on the surface of FL10. The presence of both Tindd and I-A subregion-controlled determinants on FL10-derived TaF was directly demonstrated by the adsorption of TaF with immunoadsorbents prepared with monoclonal antibodies. The Igh-1-linked T cell alloantigen, Tsud, was not found on TaF. Further experiments indicated that Tindd is present on the antigen-binding polypeptide chain and not on the second chain bearing the I-A determinant. Despite the presence of the Tindd determinant on hybridoma-derived TaF, augmentation induced by TaF was restricted by the H-2 type of the responding mice and not by the Igh-1 allotype.

Animals↗
PubMed1983

Functional immunoglobulin M production after transfection of cloned immunoglobulin heavy and light chain genes into lymphoid cells.

The rearranged immunoglobulin heavy (mu) and light (kappa) chain genes cloned from the Sp6 hybridoma cell line producing immunoglobulin M specific for the hapten 2,4, 6-trinitrophenyl were inserted into the transfer vector pSV2-neo and introduced into various plasmacytoma and hybridoma cell lines. The transfer of the mu and kappa genes resulted in the production of pentameric, hapten-specific, functional IgM.

Animals↗
PubMed1982

Two loci in I-J subregion of the H-2 complex controlling molecules selectively expressed on suppressor and helper T cells.

Different batches of alloantiserum directed at the I-J subregion products of the H-2 major histocompatibility complex (anti-I-J) induced either suppression or augmentation of the in vitro secondary antibody response when added in a minute quantity to the culture of primed spleen cells. The suppressive or augmenting effect of the individual antiserum was found to be determined by its predominant specificity for either one of the two different molecules, both encoded in the I-J subregion, that were selectively expressed on functionally different subsets of T cells, i.e., suppressor (Ts) and helper (Th2) T cells. This was determined by the differential absorption of antiserum with Lyt-1+ and Lyt-2+ T cells as well as with suppressor hybridomas that express an I-Jk product. It was found that the absorption of an anti-I-J antiserum with Lyt-1+ T cells resulted in the loss of activity to eliminate a set of helper T cells (Th2) while leaving the ability to affect antigen-specific suppressor T cells (Ts). The absorption of the same antiserum with either Lyt-2+ T cells or suppressor hybridomas eliminated the activity to kill Ts but not Th2. Thus, the results indicate that the I-J subregion accommodates two or more loci that code for discrete molecules expressed on functionally different subsets of T cells. Because the simple addition of a minute quantity of antisera to the culture resulted in the modulation of antibody response presumably by affecting these two sets of T cells, it is suggested that I-J subregion products act as functional molecules in regulatory cell interactions.

Animals↗
PubMedDate not supplied

Transfer of a cloned immunoglobulin light-chain gene to mutant hybridoma cells restores specific antibody production.

The expression of immunoglobulin (Ig) genes is regulated at several levels. For example, although kappa-chain production requires a DNA rearrangement that juxtaposes variable and joining segments, this rearrangement is not sufficient for kappa-chain gene expression; that is, some cell types do not permit immunoglobulin production. The mechanisms responsible for the regulation of the expression of rearranged immunoglobulin genes are poorly understood. The technique of modifying cloned genes in vitro and transferring the modified genes to cells in culture provides a tool for identifying the structural features required for gene expression. To analyse immunoglobulin genes in this manner, however, it is first necessary to use, as recipients, cells that normally permit immunoglobulin production. We report here that a cloned kappa-chain gene is expressed in immunoglobulin-producing hybridoma cells. Furthermore, the product of the transferred kappa-chain gene is capable of restoring specific antibody production to the transformed cells.

Animals↗