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T Uchiyama

Publications and source records attributed to T Uchiyama.

At least 19 recordsLinked to original sources
PubMed1992

Pseudo-high affinity interleukin 2 (IL-2) receptor lacks the third component that is essential for functional IL-2 binding and signaling.

Functional studies of the interleukin 2 receptor (IL-2R) of two (ED515-D and Kit225) IL-2-dependent and three (ED515-I, 3T3-alpha beta 11, and Hut102) IL-2-independent cell lines were done. All of these cell lines appeared to express high as well as low affinity IL-2R. However, ED515-I and 3T3-alpha beta 11, which expressed the IL-2R beta chain, did not bind IL-2 at all when IL-2 binding to their IL-2R alpha chain was blocked with anti-Tac monoclonal antibody, whereas the intermediate affinity binding in ED515-D, Kit225, and Hut102 cells remained. We tentatively called the high affinity IL-2R of the former cells pseudo-high affinity IL-2R. The dissociation constant of pseudo-high affinity IL-2R was higher than that of ordinary high affinity IL-2R. Internalization of cell-bound 125I-IL-2 into ED515-I and 3T3-alpha beta 11 cells was less efficient than that into ED515-D cells. The addition of IL-2 neither promoted cell growth nor upregulated IL-2R alpha chain expression in ED515-I and 3T3-alpha beta 11 cells. Furthermore, tyrosine phosphorylation of the cellular proteins (p120, p98, p96, p54, and p38) was induced or enhanced in response to the addition of IL-2 in ED515-D and Kit225 cells, but not in the cell lines expressing pseudo-high affinity IL-2R. Finally, 125I-IL-2 crosslinking followed by SDS-PAGE analysis showed an 80-kD band corresponding to p65 + IL-2, in addition to bands corresponding to IL-2R alpha and beta chain + IL-2 in cells bearing ordinary high affinity IL-2R but not in cells with pseudo-high affinity IL-2R. Taken together, we consider that another protein whose molecular mass is approximately 65 kD is functionally important in IL-2 binding and subsequent signal transduction and may be the third component of IL-2R.

3T3 Cells↗
PubMed1992

Interleukin-2 (IL-2) induces erythroid differentiation and tyrosine phosphorylation in ELM-I-1 cells transfected with a human IL-2 receptor beta chain cDNA.

The molecular mechanism of erythroid differentiation has been still ill-defined. In this study, we introduced a human interleukin-2 receptor (IL-2R) beta chain cDNA into ELM-I-1 cells which differentiated into hemoglobin-positive cells in the presence of erythropoietin (Epo), and established the transformant which expressed IL-2R beta chain. In this transformant, we revealed that IL-2 induced erythroid differentiation and the same pattern of tyrosine phosphorylation as Epo. These data suggest that tyrosine phosphorylation is involved in signal transduction pathway of erythroid differentiation. It is also implicated that the Epo and IL-2 receptor system share a common signal transduction pathway.

Animals↗
PubMed1992

Report of a patient with POEMS/Takatsuki/Crow-Fukase syndrome associated with focal spinal pachymeningeal amyloidosis.

The authors present the results of an autopsy of a 67-year-old Japanese man with POEMS/Takatsuki/Crow-Fukase syndrome (P/T/CFS) diagnosed in 1972. Each component of the syndrome was gradually recognized after the resection of lumbar vertebral solitary plasmacytoma in 1967. The patient died in 1989 of generalized infection and renal failure. Autopsy revealed in the vertebral canal between the fifth and seventh thoracic vertebrae dorsal pachymeningeal fibrosis, with prominent amyloid deposition that oppressed the spinal cord. This condition was consistent with the final neurologic manifestation of the patient, bilateral motor and sensory disturbance below the sixth thoracic level. Myelopathy remained clinically unnoticed because neurologic disturbance had begun as peripheral polyneuropathy. Normocellular marrow with heterogeneously scattered lambda light chain-positive plasma cells and degeneration of the myelinated fibers of sciatic nerve also were observed. This is the first report of focal spinal amyloidosis associated with P/T/CFS.

Adult↗
PubMed1992

The third molecule associated with interleukin 2 receptor alpha and beta chain.

It is known that the affinity cross-linking study of the human high-affinity Interleukin 2 (IL-2) receptor reveals triplet bands consisting of 70 kDa alpha chain(Tac)-IL-2 and the 90/80 kDa doublet. We found the cell lines lacking the lower band of the doublet in spite of the expression of both alpha and beta chains. No IL-2 binding was detectable in the presence of anti-Tac antibody in these cells. Immunoprecipitation from the cell extract of [125 I] IL-2-cross-linked T cells with anti-beta chain polyclonal IgG detected the upper band, but not lower band of the doublet. These data suggest that the lower band of the doublet represents an unknown IL-2-binding protein (p65) distinct from the beta chain and this molecule may be involved in the intermediate-affinity IL-2 binding together with the beta chain.

3T3 Cells↗
PubMed1992

Signal transduction by interleukin 2 in human T cells: activation of tyrosine and ribosomal S6 kinases and cell-cycle regulatory genes.

The early events of signal transduction associated with interleukin-2 (IL-2) binding to its receptor were examined using a human IL-2 dependent T-cell line, Kit225. Cell cycle analysis showed that 90% of Kit225 cells were in the G0/G1 phase after a 72-hr incubation in the absence of exogenous IL-2. At this point, stimulation of the cells with IL-2 resulted in the rapid initiation of RNA and DNA synthesis by 9 and 20 hr, respectively. Within 5 min after addition of IL-2, rapid activation of tyrosine and ribosomal S6 kinases was detected. Addition of IL-2 also increased mRNA levels for c-fos, c-myc, IL-2 receptor alpha, and IL-2 receptor beta chain. These events increased in the absence of detectable changes in free cytosolic [Ca2+]i, inositol phosphate metabolism, or the activity of several kinases including cAMP-dependent protein kinase, Ca2+/calmodulin-dependent protein kinase, or protein kinase C. These findings demonstrate that the signals triggered by IL-2 binding to its receptors are quickly transduced into the nucleus with increased mRNA transcription of activation-associated genes. Furthermore, the data indicate that tyrosine and ribosomal S6 kinases may be important for IL-2-induced cell growth.

Calcium↗
PubMed1992

Diseases associated with HTLV-I: virus, IL-2 receptor dysregulation and redox regulation.

HTLV-I, the etiological agent in adult T-cell leukemia, has also been strongly implicated in a number of non-neoplastic T-cell-associated diseases. Here, Junji Yodoi and Takashi Uchiyama review these associations and focus on the emerging concepts of IL-2R dysregulation and redox regulation by adult T-cell leukemia-derived factor in the pathogenesis of HTLV-I-related diseases.

Gene Products, tax↗
PubMed1992

Chemotactic factor in the pregnant rabbit uterine cervix.

OBJECTIVE: Neutrophil accumulation is one of the characteristic changes observed in uterine cervical stroma at term pregnancy, but chemotactic activity in the tissue is obscure. Our study examined the existence and production of chemotactic factor in the rabbit uterine cervix. STUDY DESIGN: Uterine cervical explants of rabbits at term pregnancy and nonpregnant rabbits were cultured with and without interleukin-1 alpha. Rat neutrophilic chemotaxis in culture media was evaluated with a Boyden chamber. RESULTS: Tissue extract from the pregnant rabbit uterine cervix at term pregnancy contained more chemoattractive activity than the nonpregnant cervix. Production of chemoattractant from cultured rabbit cervical explants at term pregnancy was also higher than that from nonpregnant explants. The addition of interleukin-1 alpha to the culture system promoted its production. This chemoattractant was characterized as a true chemotactic factor and heat-stable and trypsin-sensitive protein with an apparent relative molecular mass of 16,200. So far, these properties are very similar to those of the interleukin-8 family. Rabbit uterine cervical fibroblast is characterized as a chemotactic factor-producing cell in the rabbit uterine cervix. CONCLUSION: These results indicate that interleukin-8-like chemotactic factor participates in the cervical ripening at term pregnancy and that the production of this factor is controlled effectively by interleukin-1.

Animals↗
PubMed1992

Rickettsia japonica sp. nov., the etiological agent of spotted fever group rickettsiosis in Japan.

We propose the name Rickettsia japonica sp. nov. (with type strain YH [= ATCC VR-1363]) for a serologically specific species of spotted fever group rickettsiae that are pathogenic for humans (J. Infect. Dis. 159:1122-1126, 1989; J. Clin. Microbiol. 28:1177-1180, 1990). The biologic and genomic characteristics of the organism (G+C content, 31.2 +/- 0.7 mol%) are essentially the same as those of other pathogenic spotted fever group rickettsiae, although the R. japonica isolates cause a persistent infection in Vero cells for many subcultures.

Animals↗
PubMed1992

Involvement of HLA class II molecules in acquisition of staphylococcal enterotoxin A-binding activity and accessory cell activity in activation of human T cells by related toxins in vascular endothelial cells.

Human umbilical vascular endothelial cells (HUVEC) express HLA class II molecules upon stimulation with recombinant human interferon-gamma (IFN-gamma). Staphylococcal enterotoxin (SE) A (SEA)-binding assay using [125I]-SEA showed the presence of specific SEA binding in HUVEC stimulated with IFN-gamma but not in unstimulated HUVEC. Levels of HLA class II expression and SEA-binding increased as the IFN-gamma concentration and the period of stimulation were increased. Binding of [125I]-SEA to the IFN-gamma-stimulated HUVEC was reduced markedly by an anti-DR/DP MoAb. T cells produced IL-2 upon stimulation with a group of SEs (SEA, SEB, SEC, SED and SEE) in the presence HUVEC stimulated with IFN-gamma but not in the presence of control HUVEC. The level of accessory cell activity in the IFN-gamma-stimulated HUVEC was related to the level of HLA class II expression and SEA-binding activity. Antibodies to HLA class II molecules almost completely inhibited the response. These results indicate that HLA class II molecules are directly involved in the acquisition of these activities in HUVEC.

Antigen-Presenting Cells↗
PubMed1992

Relative abilities of distinct isotypes of human major histocompatibility complex class II molecules to bind streptococcal pyrogenic exotoxin types A and B.

The relative ability of distinct isotypes of human leukocyte antigen class II molecules to bind streptococcal pyrogenic exotoxins A and B (SPE A and SPE B, respectively) was investigated by a direct-binding assay with 125I-labeled toxin for SPE A and by a functional assay system measuring the accessory cell activity of human leukocyte antigen class II transfectants in toxin-induced T-cell activation for SPE A and SPE B. SPE A binding was observed in L cells transfected with DQw1 genes. By contrast, it was not detected in L cells transfected with DR2, DR4, DPw4 or DP(Cp63) genes. All the transfectants supported SPE-induced interleukin-2 production by human T cells except the DP transfectants for SPE B. Levels of accessory cell activity were low in the DP transfectants induced by stimulation with SPE A and in the DR and DP transfectants induced by SPE B. The results indicate that SPE A and SPE B bind well to DQ molecules, less well to DR molecules, and very weakly to DP molecules.

Animals↗
PubMed1992

Production and epidemiological application of monoclonal antibody specific for Salmonella O5-antigen.

Salmonella typhimurium is an important causative agent of acute gastroenteritis (food poisoning), and the decision of the source of infection urgently requires epidemiological investigation. There are two types of S. typhimurium, O5-antigen-carrier type (O5(+)-antigen type) and noncarrier type (Copenhagen antigen type). On the assumption that serological differentiation of the types is effective for epidemiological exploration for the source of infection, we produced a monoclonal antibody, TMY1, specific for the O5-antigen. We classified S. typhimurium identified as the causative agent of mass outbreaks of acute Salmonella gastroenteritis according to the O5-antigen type, by using the TMY1. As a result, the bacterium in each outbreak was classified as the O5(+)-antigen type or the Copenhagen antigen type based on the difference in reactivity with TMY1. S. typhimurium isolated from calves in mass outbreaks of diarrhea and from animals with various diseases were also classified by TMY1 according to the O5-antigen type, and TMY1 was found to be as useful as in human cases. From this confirmation, TMY1 was demonstrated to be useful as a marker for epidemiological investigation of the source of infection by the O5-antigen type of S. typhimurium.

Agglutination Tests↗
PubMed1992

[Anthracycline cardiotoxicity evaluated by digitized M-mode echocardiography].

Ten patients with malignant diseases whose mean age was 20.0 +/- 13.2 years received anthracycline derivatives therapy and were evaluated for their left ventricular systolic and diastolic functions by computer-assisted digitized M-mode echocardiography. Fractional shortening (%FS), a parameter of systolic function, was measured. The first derivative of left ventricular dimension change (peak LV dD/dt), posterior wall thinning (peak LVPW thinning rate) and interventricular septum thinning (peak IVS thinning rate) were used as indices of diastolic function. Blood pressure (BP) was measured noninvasively at the end of the echocardiographic examination and hemoglobin concentration (Hb) was measured on the same day. These examinations were performed immediately before administration of anthracycline and one week and one month after the last administration. Statistical analyses were performed using the Student's t-test. The mean BP, HR, LVDd, LVDs, LVPW and IVS remained unchanged following the drug administration. %FS did not change significantly; 36.8 +/- 6.3%, before the administration, 35.3 +/- 6.5%, one week after the administration, and 36.5 +/- 5.1%, one month after the administration. Peak LVdD/dt and the peak LVPW thinning rate decreased appreciably from 4.46 +/- 1.10 to 3.76 +/- 1.08, and from 7.99 +/- 1.55 to 6.41 +/- 1.04, respectively, one week after the administration. The peak IVS thinning rate decreased from 3.54 +/- 0.81 to 2.99 +/- 0.79 after one week (p < 0.01). All of these values returned to the control levels in one month after the drug administration. We concluded that the indices of left ventricular diastolic function were more sensitive for detecting cardiac impairment than those of systolic function during the course of anthracycline therapy.

Adolescent↗
PubMed1992

[A study of complications of hepatic arterial infusion catheter].

We studied complications of the infusion catheter, which were implanted in the hepatic artery under laparotomy, and then connected with an implantable infuser port in patients with hepatocellular carcinoma (n = 32) and metastatic liver tumor (n = 11). Infuse-A-Port catheter was used for 31 cases (A group), and Anthron P-U catheter for 12 cases (B group). In B group, the cannulation method was changed; the catheter was placed in the hepatic artery via the gastroduodenal artery, which was ligated and cut to prevent kinks in the catheter. In the A group, 17 cases (54.8%) showed complications such as dislocation of the catheter tip (7 cases) including penetrating duodenal ulcer (2 cases), arterial occlusion (6 cases), injury of catheter (2 cases) and occlusion of the infuser port (2 cases). One case, however, having a fistula between the hepatic artery and the duodenum, died of sudden massive bleeding. In the B group, 3 cases (25.0%) showed complications such as dislocation of the catheter tip (1 case) and arterial occlusion (2 cases). The catheter in B group lasted longer than that in A group. Thus, our cannulation technique using Anthron P-U catheter may decrease the catheter complications.

Catheters, Indwelling↗
PubMed1992

Pancreatic pleural effusion: case report and review of 113 cases in Japan.

A patient with pancreatic pleural effusion in whom a fistulous tract was demonstrated by computed tomography (CT) is presented, and reports on 113 cases of this entity in the Japanese literature are reviewed. The most common (99%) underlying cause of this entity was chronic alcoholic pancreatitis. In most cases, the patients complained of chest symptoms (68%), and complained of abdominal symptoms less frequently (24%). It is important to maintain suspicion for this entity in patients with chronic alcoholic pancreatitis who have unexplained pleural effusion. Surgical intervention was required in 58 of 95 recorded cases. With care, the prognosis of pancreatic pleural effusion was good. Recently, as endoscopic retrograde pancreatography (ERP) and CT have been performed more frequently, the mechanisms of the pathogenesis of pancreatic pleural effusion has been determined. We stress that ERP and CT should be performed to direct surgical therapy and learn more about the mechanisms involved in the pathogenesis of pancreatic pleural effusions.

Alcoholism↗
PubMed1992

Phorbol esters up-regulate p55 and down-regulate p75 expression of interleukin-2 receptors in human T cells.

We examined the effects of phorbol esters on the expression of interleukin 2 receptors (IL-2R) in T cell clones. By flow cytometric analysis, we found that phorbol esters up-regulated IL-2R p55 expression, while they down-regulated p75 expression. The expression of IL-2R p55 in T cell clones treated with phorbol esters showed an initial transient and marginal decrease, which was followed by a progressive increase after 6 h of incubation. On the other hand, the expression of IL-2R p75 progressively decreased to a minimum plateau level. Down-regulation of p75 was also revealed in cells treated with diacylglycerols instead of phorbol esters, but there was no up-regulation of p55 in these cells. Moreover, in the presence of cycloheximide, phorbol esters down-regulated p75 expression but did not up-regulate p55 expression. Therefore, it seems that a transient activation of protein kinase C (PKC) is sufficient to down-regulate p75, but not to up-regulate p55, and that a novel protein synthesis is required to increase p55 expression.

Down-Regulation↗
PubMed1992

[Atypical leukemia accompanied by vitamin B12 deficiency].

A 76 year old female with atypical leukemia complicated by vitamin B12 deficiency demonstrated marked fluctuation in blast percentage and hemopoiesis over 8 month period. She underwent surgical removal of pancreas head cancer 5.5 years ago. In January 1989 severe pancytopenia and mild increase of bone marrow blast were found. Blood transfusions and inadvertent administration of Vitamin B12 resulted in alleviation of pancytopenia and decrease in blast percentage. Several months later her bone marrow blast exceeded 30%, when serum B12 concentration was below 90 pg/ml. B12 injection and blood transfusion resulted in significant improvement in her hematological condition, but shortly thereafter she died of fulminant hepatitis. Her bone marrow cells showed a polyclonal constitution, as assessed by the RFLP-methylation technique using the PGK gene as a probe. The coexistence of leukemic- and normal clones under Vitamin B12 deficiency conditions and the differing behavior of such clones to B12 supplementation may explain the unusual clinical course observed in this patient.

Aged↗