Search PubMed⌕ Search

Biomedical subjects

N Yamagata

Publications and source records attributed to N Yamagata.

At least 37 records · Page 2Linked to original sources

Analysis of HLA-DM polymorphisms in sarcoidosis.

Sarcoidosis is a multisystemic granulomatous disorder showing significant increases in the HLA-DRB1*11, *12, *14 and *08 alleles in the Japanese population. To evaluate the role of polymorphism in the DMA and DMB genes in predisposition to sarcoidosis, seventy Japanese patients with sarcoidosis and 95 unrelated healthy controls were analyzed in the third exon polymorphisms within the DMA and DMB genes by the PCR-RFLP method. There were no differences in the distribution of DMA alleles between the patient and control groups. The frequency of DMB*0102 was higher (p < 0.05) and that of DMB*0101 was lower (p < 0.05) in the patients than in the healthy controls. However, this association and negative association could be explained by linkage disequilibrium with the disease-associated DRB1 alleles. The DMA and DMB genes do not primarily confer the susceptibility to sarcoidosis.

Adult↗

t(7;11) and trilineage myelodysplasia in acute myelomonocytic leukemia.

A 48-year-old Japanese man was admitted to our hospital because of general fatigue, nasal bleeding, and petechiae on his extremities. He was diagnosed with acute myelomonocytic leukemia with trilineage myelodysplasia (T-MDS). Chromosomal analysis of bone marrow cells revealed t(7;11)(p15;p15), which has been rarely reported but known to be characteristic of Japanese patients. Although t(7;11)(p15;p15) has been reported mainly in acute myelogenous leukemia (AML), it can be occasionally found in so-called stem cell diseases such as chronic myelogenous leukemia or chronic myeloproliferative disorders. Therefore, t(7;11)(p15;p15) might affect trilineage progenitors or stem cells as well as myeloid lineage cells, subsequently resulting in AML with T-MDS, as in our case reported here.

Antineoplastic Combined Chemotherapy Protocols↗

Genetic polymorphisms of the major histocompatibility complex-encoded antigen-processing genes TAP and LMP in sarcoidosis.

Sarcoidosis is a granulomatous disease showing a significant increase in the HLA-DR5, -DR6, and -DR8 associated alleles in Japanese. To investigate whether the class I antigen-processing genes, encoded within the MHC class II region between the HLA-DP and -DQ loci, are involved in determining the susceptibility to sarcoidosis, TAP1, TAP2, and LMP2 alleles were analyzed by the PCR-RFLP method in 85 Japanese patients with sarcoidosis and 91 healthy controls. There were no significant differences in the distribution of TAP1 and LMP2 alleles between the subgroups of the patients and controls positive or negative for DR5, DR6, and DR8. A significant decrease in the frequency of TAP2*0201 was found among the patients negative for DR5, DR6, and DR8 as compared to the DR-matched controls (p < 0.05), but this could be explained by its linkage disequilibrium to the negatively associated allele DR1. These findings suggest that the TAP or LMP2 gene is not primarily involved in the susceptibility to sarcoidosis. In the course of this study, a linkage disequilibrium was observed in the Japanese population between TAP1 and TAP2 alleles, TAP1*0201 and TAP2*0102.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

LMP7 polymorphism in Japanese patients with sarcoidosis and Behçet's disease.

To evaluate the influence of the MHC-linked LMP7 gene on disease susceptibility in HLA class I and class II-associated diseases, the distribution of LMP7 alleles was determined using the PCR-RFLP method in 69 Japanese patients with Behçet's disease, 65 patients with sarcoidosis, and 100 unrelated healthy controls. No differences were found between either of the patient groups and the healthy control group, indicating that LMP7 allelic variation may not contribute to the pathogenesis of either Behçet's disease or sarcoidosis. We also analyzed linkage disequilibria between LMP7 and HLA class II alleles in Japanese populations.

Alleles↗

Expression of adhesion molecules on myeloma cells.

We investigated the expression of adhesion molecules including LFA-1 alpha (CD11a), Mac-1 (CD11b), LFA-1 beta (CD18), VLA-beta 1 (CD29), H-CAM (CD44), VLA-4 (CD49d), VLA-5 (CD49e), ICAM-1 (CD54), N-CAM (CD56), LFA-3 (CD58), VNR-beta (CD61), and LECAM-1 (CD62L) on fresh myeloma cells and human myeloma cell lines. By two-color flow cytometric analysis with anti-CD38 antibody, we demonstrated that myeloma cells were located in the strongly CD38-positive (CD38++) fractions. Fresh myeloma cells were obtained from 28 patients with multiple myeloma (MM) and 3 patients with plasma cell leukemia (PCL). All myeloma cells expressed VLA-4 on their surface. Most of the myeloma cells also expressed VLA-5, ICAM-1, and LFA-3, H-CAM was strongly expressed in 3 cases of PCL and 2 cases of aggressive myeloma, and moderately expressed in other MMs. N-CAM was expressed in 68% of MMs, but none of the 3 PCLs. LFA-1 was expressed in two cases of aggressive myeloma, but not expressed in other non-aggressive myelomas. Most of the myeloma cells did not express Mac-1, VNR-beta, or LECAM-1. These results suggest that VLA-4, VLA-5, ICAM-1, LFA-3, and H-CAM are involved in cellular interaction and migration in MM, and that the expression of N-CAM and LFA-1 varies with disease activity in MM.

ADP-ribosyl Cyclase↗

Genetic polymorphisms in the keratin-like S gene within the human major histocompatibility complex and association analysis on the susceptibility to psoriasis vulgaris.

Psoriasis vulgaris is associated with the HLA-Cw6 and Cw7 antigens. However, it has not yet been clarified if the HLA-Cw6 and Cw7 genes themselves are the susceptible gene related to this disease or if it is some other non-HLA gene in a linkage disequilibrium with these HLA-C alleles. The S gene, recently identified in the HLA class I region 160 kb telomeric of HLA-C, encodes a keratin-like protein and is expressed specifically in the granular layer of the epidermis. Therefore, it is tempting to speculate that the S gene is one of the strong candidate genes responsible for the pathogenesis of psoriasis vulgaris. Direct sequencing of the first and second exon of the S gene after polymerase chain reaction (PCR) amplification has allowed the identification of two diallelic polymorphic sites in exon I and seven diallelic polymorphic sites in exon 2, three among which result in amino acid exchanges, a Ser-Phe substitution at amino acid position 186, a Gly-Val substitution at position 393 and a Ser-Leu substitution at position 394. No significant difference in the dimorphic distributions of the S gene was observed between the patients with psoriasis vulgaris and healthy controls, suggesting that the susceptible gene for psoriasis is not the S gene itself.

Disease Susceptibility↗

Effect of egg white on serum cholesterol concentration in young women.

In a previous study we observed favorable effects of egg white on serum lipids in rats and mice. The present study was designed to elucidate these effects in 24 female university students with moderate hypercholesterolemia. About 30% of total protein was supplied with egg white, tofu or cheese. The experiment was conducted for a complete menstruation cycle of each subject. Lipid intake was about 30% of total energy intake. The energy intake of each subject was constant throughout the experiment. Body weight was measured every morning. Daily activity was measured by a pedometer. Blood was withdrawn after an overnight fast on the first, 15th and last days and serum lipids were measured. Body weight was measured every morning. Daily activity was measured by a pedometer. Blood was withdrawn after an overnight fast on the first, 15th and last days and serum lipids were measured. Body weight and daily activity were maintained in all the groups throughout the experiment. The egg white group showed a similar decrease in the total cholesterol (Total-C) concentration but a greater increase of high-density lipoprotein cholesterol (HDL-C) concentration as compared to the tofu group and a greater decrease in Total-C and low-density lipoprotein cholesterol (LDL-C) concentrations and a greater increase in the HDL-C concentration as compared to the cheese group (p < 0.05). The results indicate the favorable effects of egg white in the control of hypercholesterolemia.

Adult↗

[Natural killer cell lymphoma having a nodular shadow in the lung as an initial finding, developed to leukemia complicated with hemophagocytic syndrome at the time of relapse].

A 57-year-old female was admitted to Uji hospital for the further evaluation of nodular shadow on her right lung. During the period of admission, she developed cervical lymph node swelling. She was diagnosed as having malignant lymphoma (diffuse, small cleaved cell) by lymph node biopsy. She received combined chemotherapy and obtained partial remission for seven months until she developed fever and pancytopenia. Laboratory data showed increased number of large granular lymphocytes (LGLs) in blood. Bone marrow revealed increased number of LGLs with hemophagocytosis by macrophage. Surface marker analysis revealed LGLs were positive for CD2 CD16, and CD56 and negative for CD3, CD4, CD8, and CD20. T-cell receptor genes beta and gamma were in germ line configuration. Analysis of Epstein-Barr virus genome using termini probe indicated a monoclonal proliferation of LGLs. Reexamination of the biopsy specimen of lymph node revealed LGLs which was negative for CD3 and CD20. The patient was diagnosed as a leukemic phase of natural killer (NK) cell lymphoma complicated with hemophagocytic syndrome (HPS). Serum levels of interferon-gamma, macrophage colony-stimulating factor, granulocyte colony-stimulating factor, and interleukin-6 increased, which might be related to HPS.

Antigens, CD↗

[Three cases of secondary acute myeloid leukemia after long-term treatment with oral etoposide].

Three cases of secondary acute myeloid leukemia (AML) that developed after long term treatment with oral etoposide were reported. Case 1 was a 72-year-old male in whom small cell lung cancer was diagnosed in January 1987. He developed AML (M4) in February 1993 after long-term treatment with oral etoposide (total dose 14,650 mg) t(9; 11) (p21; q23) with rearrangement of MLL genes was recognized. Case 2 was a 68-year-old female non-Hodgkin's lymphoma (NHL) was diagnosed in February 1989. AML (M4Eo) with inv(16) (p13q22) developed in March 1994 after long-term treatment with oral etoposide (total dose 5,100 mg). Case 3 was a 39-year-old male in whom NHL was diagnosed in January 1991. He developed AML(M2) with t(11; 19) (q23; p13) in May 1994 after long-term treatment with oral etoposide (total dose 20,450 mg). These three cases suggest that long-term treatment with oral etoposide may be associated with a risk of developing a secondary AML in patient with malignancies.

Administration, Oral↗

Mobilization of peripheral blood progenitor cells by high-dose Ara C, VP-16 and recombinant human granulocyte colony-stimulating factor: factors affecting progenitor cell yields.

Forty seven patients with hematological malignancies were treated with high doses of cytosine arabinoside (Ara C; 12 g/m2) and etoposide (VP-16), followed by recombinant human granulocyte colony-stimulating factor (rhG-CSF; 50 micrograms/m2). Peripheral blood progenitor cells (PBPC) were collected during rapid leukocyte recovery using a CS-3000 blood cell separator. A blood volume of 9 liters was processed in each apheresis, with 162 apheresis procedures performed. The mean numbers of mononuclear cells (MNC) and colony-forming unit granulocyte-macrophage (CFU-GM) harvested per apheresis were 4.4 x 10(8)/kg and 142.5 x 10(4)/kg, respectively. A sufficient number of CFU-GM for engraftment (> 30 x 10(4)/kg) could be harvested by a single apheresis in 35 of 47 patients (74%). Various factors that influence the collection of progenitor cells were analyzed by univariate and multivariate analyses. The number and duration of previous chemotherapy cycles were the most significant factors affecting CFU-GM yield. In patients with malignant lymphoma, age also had an influence in addition to these two factors. MNC harvested had an impact on CFU-GM yields by univariate analysis. These observations suggest that high-dose Ara C plus VP-16 followed by G-CSF is an effective regimen for harvesting PBPC. PBPC should be collected in the early stage of first-line chemotherapy.

Adolescent↗

Establishment of a novel myeloma cell line KPMM2 carrying t(3;14)(q21;q32), which proliferates specifically in response to interleukin-6 through an autocrine mechanism.

We established a new human myeloma cell line, KPMM2, which proliferates specifically in response to IL-6 via an autocrine mechanism. The proliferative response of KPMM2 cells to exogenous IL-6 was significantly stimulated in a dose-dependent manner. The growth was markedly inhibited by an anti-IL-6 mAb and an anti-IL-6 receptor (IL-6R) mAb in a dose-dependent manner. KPMM2 cells expressed IL-6 and IL-6R mRNA by RT-PCR. Flow cytometric analysis showed cell surface expression of IL-6R. IL-6 protein was detected in the culture supernatant by ELISA. IL-11, oncostatin M and leukemia inhibitory factor had no effect on the proliferation of KPMM2 cells although interferon-alpha and interferon-gamma inhibited the growth. Furthermore, KPMM2 cells bore a t(3;14)(q21;q32) translocation and this finding is of potential interest for future studies in the light of the nuclear protein BM28 (CDCL1, for cdc-like 1) mapped on 3q21, which plays an important role in the cell cycle. In this report, we demonstrated completely an IL-6-dependent autocrine growth mechanism in KPMM2 cell line. This cell line may be useful to investigate the pathogenesis of multiple myeloma and to evaluate the therapeutic potential of IL-6 blocking agents in vitro and in vivo.

Aged↗

Structure of the most superficial layer of articular cartilage.

We studied the most superficial layer of macroscopically normal articular cartilage obtained from human femoral heads, using polarising microscopy and SEM. The most superficial layer, 4 to 8 microns thick, was acellular consisting of collagen fibrils. This layer could be peeled away as a thin film, with no broken collagen fibrils on its inferior surface or on the surface of subjacent cartilage layers. The orientation and diameter of collagen fibrils were different on these two surfaces. Our findings suggest that the most superficial layer is an independent one which is only loosely connected to the fibrous structure in the layer deep to it.

Cartilage, Articular↗