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Junji Nishimura

Publications and source records attributed to Junji Nishimura.

29 records · Page 2Linked to original sources
PubMed2003

[Changes in the contractility of the NIH3T3 fibroblast induced by the over-expression of CPI-17].

The role of protein kinase C (PKC) in the regulation of contraction has been controversial. Recently, CPI-17, a PKC-potentiated inhibitor protein of PP1, has been cloned and shown to be specifically expressed in SMC. In this study, we over-expressed CPI-17 and its mutants in NIH3T3 cells, which do not express CPI-17, and examined its effect on the contractile property. For the measurement of tension, NIH3T3 cells were collected by trypsinization, mixed with type I collagen and made into a ring preparation (reconstituted ring: RR). The isometric tension developments were measured using this RR and a force transducer. The application of phorbol dibutyrate (PDBu; 0.3 microM) to RR transfected by CPI-17 induced a contraction that reached 2-3 times greater that the 10% FBS-induced contraction, while PDBu relaxed the RR transfected with vector alone (control) or CPI-17 mutants (T38A and T38E). The PDBu-induced contraction of the CPI-17 transfected RR could be inhibited by 3 microM GF109203X (PKC inhibitor) but not by 3 microM Y27632 (rho kinase inhibitor). The application of PDBu during contraction induced by 1 microM bradykinin induced further contraction in CPI-17 transfected RR, while it induced a complete relaxation in control RR. These results indicated that CPI-17 is a molecular switch that reverses the PKC mediated effect on contraction. The limited expression of CPI-17 to SMC may explain the previous observation that the effects of PKC stimulation were quite different in SMC from those of other cell types.

Animals↗
PubMed2002

Clinical significance of telomerase activity in multiple myeloma.

BACKGROUND: The clinical course of patients with multiple myeloma varies, and therefore it is important to evaluate the disease state. We studied the telomerase activity of myeloma cells as a possible prognostic factor in such patients. METHODS: Twenty five samples from patients with multiple myeloma were studied. We purified myeloma cells in bone marrow samples according to the expression of surface antigens, CD38 and CD45. CD38+/CD45- or dim cells had morphologic characteristics of myeloma cells, with a purity exceeding 95%. The telomerase activity of myeloma cells was determined by a polymerase chain reaction-based telomeric repeat amplification protocol assay. Ki-67 positivity of the purified cells was determined by flow cytometry using anti-Ki-67 antibody. The relationship between telomerase activity and prognostic factors was also examined. RESULTS: A significantly high degree of telomerase activity was detected in subjects with a serum beta2-microglobulin level > or = 6 mg/dL or at Stage III (P = 0.002). The serum C-reactive protein, lactate dehydrogenase, and creatinine levels did not correlate with the telomerase activity, but this activity did significantly correlate with Ki-67 positivity and the percentage of plasma cells in the bone marrow (r = 0.561, P = 0.004, and r = 0.397, P = 0.049, respectively). The patients with high levels of telomerase activity were thus found to have a significantly short survival time after sampling (P = 0.035). CONCLUSIONS: The measurement of the telomerase activity in myeloma cells was found to be a reliable marker for the proliferating capacity and tumor mass in myeloma patients. The telomerase activity of myeloma cells may therefore be useful as a prognostic factor.

Adult↗
PubMed2002

Mechanism of down-regulation of L-type Ca(2+) channel in the proliferating smooth muscle cells of rat aorta.

The mechanism of down-regulation of L-type Ca(2+) channel (L-VOC) was investigated in rat aortic smooth muscle cells in primary culture. On culture days 3-5, the cells actively incorporated the 5-bromo-2'-deoxy-uridine (BrdU), and did not respond to K(+) depolarization nor express alpha(1C) subunit of L-VOC. At confluence on day 8, BrdU incorporation decreased, and the cells up-regulated alpha(1C) subunit mRNA, expressed alpha(1C) subunit protein at cell periphery, and responded to K(+) depolarization. Treating the proliferating cells on day 3 with serum-free media or 10 microM PD98059, a MAP kinase kinase inhibitor, for 2 days induced the expression of alpha(1C) subunit protein and the responsiveness to K(+) depolarization. However, the serum starvation, but not PD98059, decreased the BrdU incorporation and increased the alpha(1C) subunit mRNA. It is concluded that the expression of L-VOC is substantially suppressed in the proliferating cells due to two mechanisms; a MAP kinase-mediated post-transcriptional down-regulation and the transcriptional down-regulation by additional mitogenic signals.

Animals↗
PubMed2002

Eradication of virus-infected T-cells in a case of adult T-cell leukemia/lymphoma by nonmyeloablative peripheral blood stem cell transplantation with conditioning consisting of low-dose total body irradiation and pentostatin.

We describe the case of a 55-year-old man with adult T-cell leukemia/lymphoma (ATL) in first remission who underwent nonmyeloablative allogeneic peripheral blood stem cell transplantation with conditioning consisting of 4 courses of pentostatin and low-dose total body irradiation. Complete chimerism in peripheral blood was achieved on day 42 without severe myelosuppression. Concomitantly, the proviral DNA load for human T-cell leukemia virus I (HTLV-I) in peripheral blood mononuclear cells decreased below detectable limits and was still undetectable on day 270. This fact indicates that eradication of ATL cells is feasible by induction of an alloimmune response without high-dose chemoradiotherapy.

Adult↗
PubMed2002

The mechanisms for tachykinin-induced contractions of the rabbit corpus cavernosum.

1. This study was designed to investigate the mechanisms for the contractions induced by tachykinins (substance P (SP), neurokinin A (NKA) and neurokinin B (NKB)) in the rabbit corpus cavernosum strips, using fura-PE3 fluorimetry and alpha-toxin permeabilization. 2. Tachykinins induced contractions in the rabbit corpus cavernosum in a concentration-dependent manner. The potency order was SP>NKA>NKB. 3. The tachykinin-induced contractions were enhanced by phosphoramidon (PPAD), an endopeptidase inhibitor, but not by N(omega)-nitro-L-arginine methylester (L-NAME). 4. The NK(1) receptor selective antagonist, SR 140333 significantly inhibited the tachykinin-induced contractions. Although the NK(2) receptor selective antagonist, SR 48968 alone did not influence the effects of tachykinins, it potentiated the inhibitory effect of SR 140333. The NK(3) receptor selective antagonist, SR142801 had no effect. 5. In the rabbit corpus cavernosum, tachykinins induced sustained increases in [Ca(2+)](i) and tension in normal PSS, while only small transient increases in [Ca(2+)](i) and tension were observed in Ca(2+)-free solution. 6. In alpha-toxin permeabilized preparations, tachykinins induced an additional force development at a constant [Ca(2+)](i). 7. These results indicated that in the rabbit corpus cavernosum: (1) Tachykinins induced contractions by increasing both the [Ca(2+)](i) and myofilament Ca(2+) sensitivity; (2) The tachykinin-induced [Ca(2+)](i) elevations were mainly due to the Ca(2+) influx; (3) Tachykinin-induced contractions were mainly mediated through the activation of NK(1) receptor expressed in the rabbit corpus cavernosum smooth muscle, and affected by the endopeptidase activity and (4) Tachykinins may thus play a role in controlling the corpus cavernosum tone.

Animals↗
PubMed2002

[Vitamin K2 therapy for myelodysplastic syndrome].

Vitamin K2 is reported to induce apoptosis or differentiation of leukemic cell lines in vitro. We administered a vitamin K2 analog, menatetrenone, at 45 mg daily to 23 patients with myelodysplastic syndrome (MDS): 13 patients with RA, 2 with RARS, 6 with RAEB and 2 with RAEB-T. Good response (GR) and partial response (PR) were defined as an increase of hemoglobin concentration exceeding 2 g/dl and 1-2 g/dl without transfusion, respectively. Six of the RA patients showed improvement of anemia (GR, 3 patients; PR, 3 patients). RA patients who did not have a hypocellular bone marrow and were transfusion-independent tended to be responsive to vitamin K2 therapy in combination with vitamin D3 or anabolic steroids. No adverse effect of vitamin K2 was observed, and the time required to obtain the hematological response was short, being 3 months on average. We believe that vitamin K2 therapy has potential as a treatment for patients with MDS.

Adult↗
PubMed2002

[Acute lymphoblastic leukemia with p190 type bcr/abl chimeric mRNA at relapse].

We describe the case of a 23-year-old man with acute lymphoblastic leukemia in whom the Philadelphia chromosome was first detected in the late stage of the disease. At diagnosis, the patient's leukocyte count was 39,400/microliter and leukemic cells were positive for CD10, 19, 20, 33, 34 and HLA-DR. Karyotypic analysis at diagnosis revealed 46,XY. Complete remission was achieved after the first induction therapy, but the disease recurred after 9 months. The patient underwent allogeneic peripheral blood stem cell transplantation from his HLA identical mother, but relapse occurred on day 80. The proportion of bone marrow lymphoblasts decreased transiently after donor lymphocyte infusion but later increased, and the patient died on day 362. The Philadelphia chromosome was first detected by karyotypic analysis on day 256. p190-type bcr/abl mRNA transcripts were negative following RT-PCR at the initial diagnosis, but became positive from the first relapse through the late stage. Generally, the product of the bcr/abl fusion gene has been thought to play an important role in leukemogenesis, however the present case suggests that this gene product is also related to disease progression.

Adult↗
PubMed2002

[Angioimmunoblastic T cell lymphoma (AITL) with autoimmune thrombocytopenia].

We present a case of angioimmunoblastic T cell lymphoma (AITL) with autoimmune thrombocytopenia. A 85-year-old man was admitted to our hospital with thrombocytopenia, generalized lymphadenopathy, pleural effusion, and splenomegaly in June 2000. Blood chemistry revealed hemoglobin and platelet counts of 8.8 g/dL and 26 x 10(9)/L, respectively. The level of platelet-associate-IgG was 2568.9 ng/10(7) cells. The direct Coombs test was positive. The level of serum IL-6 was 10.2 pg/ml. Megakaryocytes in the bone marrow increased. Lymph node biopsy showed diffuse proliferation of atypical lymphoid cells with a clear cytoplasm accompanied by plasma cells and small vessels. He was diagnosed as having AITL with autoimmune thrombocytopenia and hemolytic anemia. He received repeated platelet transfusion, and a limited effect of prednisolone therapy on his platelet count was observed. Combination chemotherapy lessened the extent of the lymphadenopathy and slightly elongated the interval of platelet transfusion. We next performed splenic irradiation and a slight increase in the platelet count was observed. He died of pneumonia in August 2000. Autoimmune thrombocytopenia associated with AITL is rare and the therapy containing prednisolone and chemotherapy is reported to be partly effective. Our case showed a minor response of autoimmune thrombocytopenia to splenic irradiation. Therapeutic intervention for hypersplenism should be considered if thrombocytopenia is not improved by chemotherapy alone.

Aged↗
PubMed2002

[Persistent T-cell mixed chimerism in a case of malignant lymphoma after nonmyeloablative allogeneic peripheral blood stem cell transplantation].

We describe a 51-year-old woman with recurrent follicular lymphoma from the age of 47 despite chemo-radio therapy, who subsequently underwent nonmyeloablative stem cell transplantation with conditioning consisting of fludarabine and low-dose total body irradiation (2 Gy). Myelosuppression was very mild, so the patient required no transfusions. Chimerism analysis from peripheral blood showed that T-cell mixed chimerism continued over 12 months after stem cell transplantation (the percentage of recipient T-cells was approximately 20%). Despite this, the lymphadenopathy disappeared, and the patient developed grade II acute GVHD (graft versus host disease). It has been considered that the establishment of full donor chimerism is required to induce GVHD and GVM (graft versus malignancy) effects. In this case, however, an allo-response was observed despite the persistence of T-cell mixed chimerism.

Female↗