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Biomedical subjects

K Ohshima

Publications and source records attributed to K Ohshima.

At least 217 records · Page 12Linked to original sources

Human and viral interleukin-10 in Hodgkin's disease, and its influence on CD4+ and CD8+ T lymphocytes.

The Epstein-Barr virus (EBV) is closely related to Hodgkin's disease (HD), while the BCRF-I (viral [v] IL-10) gene of the EBV is highly homologous to the human interleukin-10 (h IL-10) gene. To investigate the relationship of IL-10 and HD, we performed both immunostaining and in situ hybridization (ISH) in 30 cases of HD. The presence of EBV in Hodgkin (H) and Reed-Sternberg (RS) cells was seen in 16 of the 30 cases, by ISH of the EBV EBER-I region and/or immunostaining of latent membrane protein (LMP-I). Of the 16 EBV-positive cases, 12 also showed IL-10 antigen (Ag) in H and RS cells by immunostaining, 5 of the 16 demonstrated hIL-10 RNA by ISH and 14 of the 16 showed vIL-10 RNA. But only 2 of the 14 EBV-negative cases showed IL-10 Ag, and one of them showed hIL-10 RNA, while none demonstrated vIL-10 RNA. The T cells in the HD-involved tissues were found to be mainly CD4-positive T cells, and had no association with EBV infection. However, the lymphocytes surrounding H and RS cells were more frequently CD4 cells and rarely CD8 cells in the EBV-positive cases, in contrast with the EBV-negative cases. The above results indicate that an EBV infection influenced both cytokine synthesis and the response of T cells in HD.

CD4-Positive T-Lymphocytes↗

Molecular cloning and characterization of mouse estradiol 17 beta-dehydrogenase (A-specific), a member of the aldoketoreductase family.

Several mammalian livers contain monomeric 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) with A-stereospecificity in hydrogen transfer, which differs from the B-specific dimeric enzyme of human placenta in its ability to catalyze the oxidoreduction of xenobiotic trans-dihydrodiols of aromatic hydrocarbons and carbonyl compounds. Here, we report the isolation and characterization of a mouse cDNA clone encoding monomeric 17 beta-HSD of the liver. This clone had an entire coding region for a protein of 323 amino acid residues with a molecular weight of 37,055. The deduced sequence of the protein aligned with a high degree of identity with rat and rabbit 20 alpha-HSDs, rat and human 3 alpha-HSD/dihydrodiol dehydrogenases, and bovine prostaglandin F synthase, which are members of the aldoketoreductase family, but was distinct from human 17 beta-HSD and carbonyl reductase, members of the short chain dehydrogenases. The expression of the cDNA in Escherichia coli resulted in synthesis of a protein that was active toward androgens, estrogens, and xenobiotic substrates. The recombinant and mouse liver 17 beta-HSDs also exhibited low 20 alpha-HSD activity toward progestins, which is similar to bifunctional activity of human placental 17 beta-HSD. Therefore, the mouse enzyme was given the designation of estradiol 17 beta-dehydrogenase (A-specific). Northern analysis of mouse tissues revealed the existence of a single 1.7-kilobase 17 beta-HSD mRNA species in the liver, kidney, testis, and stomach. The liver mRNA content was considerably more abundant than those found in the other tissues, as 17 beta-HSD protein was mainly detected in the liver by Western analysis.

Amino Acid Sequence↗

Direct tumorigenic conversion of human gallbladder carcinoma cells by v-src but not by activated c-H-ras oncogene.

The roles of activated ras and src oncogene products in the acquisition of fully neoplastic phenotype by human gallbladder adenocarcinoma cells were investigated by co-transfecting non-tumorigenic HAG-I human gallbladder carcinoma cells with the pSV2neo plasmid and a plasmid carrying either activated c-H-ras or v-src oncogene. G418-resistant clones were isolated and assessed for the acquisition of anchorage-independent growth potential. Neither the 10 established clones transfected with pSV2neo alone nor the 17 clones transfected with activated c-H-ras, including 4 clones expressing the mutated p21H-ras protein, could form colonies in soft agar. By contrast, out of 10 clones transfected with v-src, 2 formed colonies in soft agar and produced tumors in athymic nude mice, the resulting progressive neoplasms being poorly differentiated adenocarcinomas. These tumorigenic clones were shown to have v-src DNA and mRNA levels with p60v-src protein, but there were no significant chromosomal alterations following tumorigenic conversion. Moreover, herbimycin A, a selective src-kinase inhibitor, markedly reduced clonogenic growth of these cells in soft agar rather than monolayer growth, suggesting that anchorage-independent growth of the v-src-transformed HAG-I cells might be driven directly by p60v-src kinase activity. Taken together, our data suggest that the fully neoplastic conversion of HAG-I cells depends on src-related tyrosine-kinase activity, but not solely on the function mediated by activated ras, thus providing evidence of an src-related signaling pathway for the acquisition of tumorigenic potential by human gallbladder adenocarcinoma cells.

Adenocarcinoma↗

Cloning, expression and tissue distribution of mouse tetrameric carbonyl reductase. Identity with an adipocyte 27-kDa protein.

We previously cloned a cDNA for pig lung tetrameric carbonyl reductase which shows significant similarity to a putative 27-kDa protein predicted from the cDNA for murine adipocyte RNA which had been increased in its differentiation [Nakanishi, M., Deyashiki, Y., Nakayama, T., Sato, K. & Hara, A. (1993) Biochem. Biophys. Res. Commun. 194, 1311-1316]. In this investigation, we isolated and sequenced a full-length cDNA for the tetrameric enzyme from a mouse lung cDNA library. It consisted of 984 bp and coded for a protein of 244 amino acid residues, of which 202 residues were identified by protein sequencing. The expression of the cDNA in Escherichia coli resulted in synthesis of a protein structurally and functionally similar to the enzyme purified from mouse lung. The nucleotide sequence of the cDNA was virtually identical to that of the cDNA for the adipocyte 27-kDa protein. Although Northern-blot analysis of mouse tissues showed that enzyme mRNA to be 1.1 kb only in lung, low expression of the mRNA in all the extrapulmonary tissues, including adipose tissue, was demonstrated by a reverse-transcription PCR method. Western-blot analysis also indicated the presence of the enzyme in the adipose tissue. This is the first report on an identification of the putative gene product of adipocytes as tetrameric carbonyl reductase, the expression of which is tissue-specifically regulated.

Adipocytes↗

A megakaryocyte analysis of the bone marrow in patients with myelodysplastic syndrome, myeloproliferative disorder and allied disorders.

A morphometric analysis was performed on aspirate clots of bone marrow to identify the presence of atypical megakaryocytes after immunohistological staining with a monoclonal antibody against Factor VIII. This study included cases of myelodysplastic syndrome (MDS), myeloproliferative disorder (MPD), aplastic anaemia (AA), idiopathic thrombocytopenic purpura (ITP), chronic myelogenous leukaemia (CML), and control cases free from any haematological disease. Quantitative and qualitative abnormalities of megakaryocytes were assessed using an image analyser and a personal computer to perform a morphometric analysis of the number (per mm2), arrangement (microns), nuclear size (microns2), cell size (microns2), nuclear size/cell size (N/C) ratio, and nuclear contour index (NCI). Micromononuclear megakaryocytes were detected in MDS, while in MPD, large over-mature magakaryocytes were observed to increase in number. In AA, the megakaryocytes decreased dramatically in number without showing any morphological abnormality. In CML, the megakaryocytes also increased without any remarkable morphological abnormality. In ITP, only the NCI increased. The above results show that MDS is characterized by the presence of atypical micromegakaryocytes, while MPD is characterized by atypical large over-mature megakaryocytes.

Antibodies, Monoclonal↗

CD30-positive anaplastic large cell lymphoma in a human T-cell lymphotropic virus-I endemic area.

Clinicopathological and cytogenetic studies were performed on specimens from 43 patients with CD30-positive anaplastic large cell lymphoma (ALCL). All patients were born and lived in a human T-cell lymphotropic virus (HTLV)-I endemic area. Twenty-one patients (48.8%) had serum anti-HTLV-I antibody suggesting the presence of adult T-cell leukemia/lymphoma (ATL). Seventeen of them showed a clonal integration of complete HTLV-I proviral DNA by the Southern blot hybridization method in materials obtained by biopsy. Their ages ranged from 37 to 81 years (median, 67.0), and they frequently presented with lymphadenopathy (82.4%) and extranodal tumors with (76.5%) as well as with rare leukemic changes (5.9%). Immunohistologically the lymphoma cells in 15 ATL patients showed a T-cell phenotype. In only one patient (5.9%) was there an expression of epithelial membrane antigen (EMA) in most of the lymphoma cells. Cytogenetically aberration of chromosome band 5q35 was not found in seven patients with HTLV-I proviral DNA. The overall median length of survival was 11.9 months for the patients with HTLV-I proviral DNA, indicating a worse prognosis compared with that of the age-matched patients with negative anti-HTLV-I antibody (P < .01). The specimens of the patients with HTLV-I proviral DNA had unique clinicopathological and cytogenetic features. These findings suggested that T-cell ALCL with HTLV-I proviral DNA should be considered to represent the lymphoma type of ATL.

Adult↗

Angiocentric immunoproliferative lesions of the skin show lobular panniculitis and are mainly disorders of large granular lymphocytes.

Eleven patients with angiocentric immunoproliferative lesion (AIL) of the skin were studied. Histologically, three patients were grouped into AIL grade II (AIL-II), whereas eight showed angiocentric lymphoma (AIL-III). All the patients' specimens exhibited lobular panniculitis. Infiltrating atypical lymphocytes in nine patients possessed electron-dense membrane bound granules in electron microscopy. Phenotypically, the lymphoid cells in the AIL-II patients were positive for CD3 epsilon; two of these showed a positive reaction to CD2, CD7, and CD8, but lacked natural killer-associated (NKa) antigens CD16, CD56, and CD57. In six AIL-III patients, lymphoma cells were positive for CD2 in all patients, CD56 in five, CD3 epsilon in four, CD7 in four, interleukin-2 beta receptor in four, a pore-forming protein in four, and CD30 in three patients. The remaining two AIL-III patients had B-cell lymphoma. By the Southern blot analysis, three patients with AIL-III showed a rearranged T-cell-receptor beta-gene or a deletion of its germline. The preceding results in nine of 11 patients suggest that abnormal or neoplastic large granular lymphocytes with the characteristics of T and NK cells have an important role in producing the angiocentric/angiodestructive features and lobular panniculitis. Clinically, all three patients with AIL-II and four with AIL-III showed liver dysfunction, cytopenia, and abnormal coagulopathy during the clinical course. Five patients with AIL-III died within 8 months. The histological grading of AIL, patients' age, and limited clinical stage of the disease seem to correlate with response to the treatment and prognosis.

Adolescent↗

Long-term follow up of visual acuity in eyes with stage 5 retinopathy of prematurity after closed vitrectomy.

PURPOSE: This study was done to determine the efficacy of closed vitrectomy on long-term visual acuity of stage 5 retinopathy of prematurity. METHODS: We studied the visual acuity of eyes that had undergone retinal reattachment by closed vitrectomy for stage 5 retinopathy of prematurity and were followed up for more than three years. RESULTS: Forty-nine eyes of 31 patients among a total of 71 eyes of 48 consecutive patients were operated on and followed up for more than three years. Retinal reattachment occurred in 29 (59%) of the 49 eyes. Six patients (eight eyes) did not respond to visual acuity testing because of mental retardation or cerebral palsy. Measured visual acuity in the remaining 21 eyes varied from no light perception in one eye, light perception in four eyes, Recognizable hand movement in three eyes, 20/2,000 to 20/200 in seven eyes, 20/200 to 20/25 in five eyes, and 20/25 in one eye. No correlation was seen between visual outcome and factors such as gestational age, birth weight, and configuration of retinal detachment. Markedly better visual acuity was obtained in eyes that underwent initial surgery within four months of birth. CONCLUSIONS: Useful vision can be obtained after reattachment of the retina by closed vitrectomy on some patients who have stage 5 retinopathy of prematurity. Better visual acuity may be obtained by earlier surgery.

Birth Weight↗

Demonstration of Epstein-Barr virus genomes, using polymerase chain reaction in situ hybridization in paraffin-embedded lymphoid tissues.

We used the polymerase chain reaction (PCR) in situ hybridization (ISH) (PCR-ISH) on sections of malignant lymphoma and nonspecific lymphadenitis to detect small amounts of Epstein-Barr virus (EBV), a DNA virus of the herpes virus family. We first surveyed the EBV DNA by Southern blot analysis and PCR, and then compared results of the two PCR/ISH methodologies with the results of simplified/sensitive ISH for the positive cases. The target of the simplified in situ (DNA-ISH) was a few copies of EBV DNA per cell, and the target of the sensitive in situ (RNA-ISH) was as many as 10(7) copies of EBV RNA per cell. When EBV DNA was detected by Southern blot, DNA-ISH, RNA-ISH and PCR-ISH all revealed EBV genomes. When PCR revealed only amplified EBV DNA, DNA-ISH showed no EBV genomes, but PCR-ISH and RNA-ISH showed EBV genomes in a few cells. When PCR showed no detectable amplified EBV DNA, all of DNA-ISH, RNA-ISH and PCR-ISH showed no genomes. These findings indicate that PCR-ISH consistently detected a few copies of the EBV virions. The PCR-ISH was as sensitive as RNA-ISH. The RNA-ISH could not detect virus if RNA was not expressed, but the PCR-ISH could detect virus without such expression. The ability to detect a single copy of a specific gene in situ has many advantages and multiple applications in molecular biology, pathology, and cell biology.

Base Sequence↗

Limited TCR V beta usage of infiltrating T cells in synovial tissues from patients with HTLV-I associated arthropathy.

Human T cell lymphotropic virus type-I (HTLV-I) is the etiologic agent of adult T cell leukemia/lymphoma and recently has also been suggested to be involved in chronic arthritis. The synovia of patients with rheumatoid arthritis (RA) contains activated T lymphocytes, with a restricted expression of T cell receptor (TCR) variable (V) beta gene segments. To characterize the T-cell populations of RA among HTLV-I carriers and noncarriers, we performed the immunohistochemical staining of CD4 and CDB, as well as a reverse transcription polymerase chain reaction (RT-PCR) to estimate the proportion of TCR beta RNA containing any particular V elements on the synovial specimens. In all but one HTLV-I carrier, the proviral DNA and/or RNA expression of HTLV-I was detected in the synovium. The CD4-positive cells proliferated markedly in the HTLV-I carriers compared with the noncarriers. In contrast to mononuclear cells in the peripheral blood, synovial T cells expressed only a few V beta transcripts, and no definite difference was observed between the carriers and the noncarriers. These results suggest that a common major antigen associated with the pathogenesis of RA may thus selectively interact with the V beta component of the TCR. Using RT-PCR, we studied the expression of the recombination-activating gene-1 (RAG-1), which was used in the V(D)J recombination of immunoglobulin and TCR genes. In all cases, RAG-1 was transcripted. The results supported the possibility that the extrathymic development of the selected TCR V beta T cells occurred in the synovia.

Adult↗

Expansion and deletion of CTG repeats from human disease genes are determined by the direction of replication in E. coli.

Several human hereditary neurological and neurodegenerative disease genes are associated with the expansion of CTG repeats. Here we show that the frequency of genetic expansions or deletions in Escherichia coli depends on the direction of replication. Large expansions occur predominantly when the CTGs are in the leading strand template rather than the lagging strand. However, deletions are more prominent when the CTGs are in the opposite orientation. Most deletions generated products of defined size classes. Strand slippage coupled with non-classical DNA structures may account for these observations and relate to expansion-deletion mechanisms in eukaryotic chromosomes for disease genes.

Base Sequence↗

The antisense homology box: a new motif within proteins that encodes biologically active peptides.

Amphiphilic peptides approximately fifteen amino acids in length and their corresponding antisense peptides exist within protein molecules. These regions (termed antisense homology boxes) are separated by approximately fifty amino acids. Because many sense-antisense peptide pairs have been reported to recognize and bind to each other, antisense homology boxes may be involved in folding, chaperoning and oligomer formation of proteins. The antisense homology box-derived peptide CALSVDRYRAVASW, a fragment of human endothelin A receptor, proved to be a specific inhibitor of endothelin peptide (ET-1) in a smooth muscle relaxation assay. The peptide was able to block endotoxin-induced shock in rats as well. Our finding of endothelin receptor inhibitor among antisense homology box-derived peptides indicates that searching proteins for this new motif may be useful in finding biologically active peptides.

Amino Acid Sequence↗

CD30 (Ki-1) expression in adult T-cell leukaemia/lymphoma is associated with distinctive immunohistological and clinical characteristics.

Twenty-one patients with CD30 (Ki-1) positive lymphoma were studied from a group of 91 patients with adult T-cell leukaemia/lymphoma. The patients were grouped into three types: diffuse CD30 positive anaplastic large cell lymphoma in 11 patients (group 1); pleomorphic type lymphoma with diffuse CD30 expression in five patients (group 2); and pleomorphic type lymphoma with positive CD30 expression in large cells but negative in medium-sized and small cells in five patients (group 3). The patients with diffuse CD30 positive lymphomas (groups 1, 2) frequently presented with extranodal tumours (68.8%) and lymph node enlargement greater than 2 cm in diameter (50%), and rarely with leukaemic changes, bone marrow involvement and hypercalcaemia (one case of each). Patients in group 3 rarely had extranodal tumours, but had frequent leukaemic changes. Expression of intercellular adhesion molecule (ICAM-1; CD54) by the lymphoma cells in 13 patients (81.3%) with diffuse CD30 positive lymphomas, was significantly higher than that in 33 patients (9.1%) with CD30 negative adult T-cell leukaemia/ lymphomas. No positive reaction for epithelial membrane antigen (EMA) was found in the lymphoma cells of CD30 positive cases. The overall survival in patients with diffuse CD30 positive lymphomas was better than that of CD30 negative adult T-cell leukaemia/lymphoma patients, but showed no significant difference. These findings suggest that diffuse CD30 positive adult T-cell leukaemia/lymphoma has unusual clinical and immunohistological findings. It is also speculated that local tumour formation and leukaemic changes in such diffuse CD30 positive cases are influenced by CD54 (ICAM-1) expression by the lymphoma cells.

Adult↗

Apoptosis in histiocytic necrotizing lymphadenitis.

Cell death can now be divided into necrosis and apoptosis, which are different in their morphology, biochemistry and biological significance. The present study was designed to investigate cell death in histiocytic necrotizing lymphadenitis (HNL). The features of cell death in 10 cases of HNL were analyzed using histiomorphology, ultrastructure and in situ apoptosis detection (ApopTag) methods. Two patterns of cell death were discerned. One was apoptosis of individual cells and the other was necrosis. The first pattern could be observed in all cases and the morphological features of the dead cells were consistent with those of apoptosis, which included distinctive cell volume shrinking and chromatin condensation. The apoptotic cells and bodies could frequently be found to be phagocytosed by the histiocytes. ApopTag was positively stained in most of the morphologically apoptotic cells. By double staining, most ApopTag positive cells were found to be T lymphocytes. A previous report showed that the majority of the proliferative cells were T lymphocytes. Based on those results, if was speculated that the main pathological characteristics of HNL therefore consisted of apoptosis and the proliferation of T lymphocytes.

Adolescent↗

A case of human herpesvirus-6 lymphadenitis with infectious mononucleosis-like syndrome.

The findings of a 20 year old woman with lymphadenopathy that was probably caused by an acute human herpesvirus-6 (HHV-6) infection are reported. She clinically demonstrated various signs of acute infection such as a high fever, skin rash, liver dysfunction, leukocytosis, an elevation of the erythrocyte sedimentation rate, and a positive change of C reactive protein, which mimicked the symptoms of infectious mononucleosis, but no positive titers for an Epstein-Barr virus infection were observed. HHV-6 DNA was detected using Southern blot analysis, polymerase chain reaction, and in situ hybridization in the affected node. Histologically, the lymph node showed an enlarged paracortex and infiltration of transformed lymphocytes and immunoblast-like cells with some histiocytes and eosinophils. Almost all the transformed lymphocytes and immunoblasts were positive for UCHL-1 (CD45RO), MT-1 (CD43), and OPD-4 (CD4), and some of these positive cells demonstrated HHV-6 DNA.

Adult↗

Detection of the Epstein-Barr virus in primary gastric lymphoma by in situ hybridization.

The Epstein-Barr virus (EBV) has been shown to be associated with numerous human malignancies including Burkitt's lymphoma and nasopharyngeal lymphoepithelioma. In addition, some typical gastric adenocarcinomas were also recently reported to demonstrate EBV relevance. The present study was designed to detect EBV in primary gastric lymphoma, using the in situ hybridization (ISH) method, in which oligonucleotide probes for the EBER1 RNA and the EBV DNA W region have been used. Of the 49 cases of primary gastric lymphoma studied, which all showed B cell immunophenotype, EBER1 sequences could only be found in four cases, including two low-grade cases and two high-grade cases of histological subtypes while the number of positive cells was less than 50% of the tumor cells. In one case of low-grade mucosa associated lymphoid tissue (MALT) lymphoma, the EBER1-positive neoplastic cells were found in the regional lymph node, but the primary site of the stomach showed no positive signals. The EBV presence was further confirmed by the EBV DNA ISH. Using the ISH method, rare or occasional positive lymphoid cells (probably non-tumorous bystander cells) could be detected in 10 other cases including all histological subtypes. The present study shows that only a small proportion of primary gastric lymphoma is associated with EBV, and such positive cases could be found in both high- and low-grade histological subtypes. It is also suggested that the EBV presence in the neoplastic cells of some cases of primary gastric lymphoma is most likely a secondary phenomenon.

Adult↗

Immunohistologic studies on subpopulations of lymphocytes in cattle with enzootic bovine leukosis.

The distribution of subpopulations of lymphocytes in lymph nodes and tumors from cattle with enzootic bovine leukosis (EBL) was examined by immunohistochemistry using a panel of monclonal antibodies against leukocyte differentiation molecules of EBL. The lesions in lymph nodes could be divided into three types based on the extent of infiltration and proliferation of neoplastic cells with provirus and differential expression of leukocyte differentiation molecules. The number of B-B2+, sIgM+ cells was reduced in frequency in follicles during the neoplastic cell proliferation. CD4- and CD8-positive alpha/beta T cells and gamma/delta T cells positive for WC1 (workshop cluster designation) were also reduced in frequency in areas infiltrated with neoplastic cells. Almost all neoplastic cells were B-B2- and IgM-positive. However, there were a few B-B2- and/or IgM-negative cells or cells stained faintly in all cases. WC1+ cells were not observed in tumor tissues. However, CD4+ and CD8+ cells were observed throughout tumor tissues, suggesting a role for these cells in tumor immunity.

Animals↗

Leukomyelopathy in ataxic calves.

Seventy-three fattening calves ranging from 6 to 15 months old on a farm were affected by ataxia over a period of four months. About 10 ataxic animals recovered after the administration of various kinds of vitamins and needle puncture therapy. The principal lesions in 14 ataxic animals examined were characterized by bilateral vacuolation with axonal degeneration confined to the spinal white matter. Ultrastructurally, the vacuoles were present in the periaxonal areas and bounded by dissociated myelin lamellae. No pathogen was isolated from the visceral organs of the animals. The serum copper remained within the normal range. Possible etiological factors remain unknown in the ataxic disease.

Animals↗