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R Abe

Publications and source records attributed to R Abe.

At least 19 recordsLinked to original sources
PubMed1992

Characterization of the Mlsf system. I. A novel "polymorphism" of endogenous superantigens.

In addition to Mlsa (Mls-1a) and Mlsc (Mls-2a, Mls-3a), we and others have recently described a third set of stimulatory minor lymphocyte stimulating (Mls) determinants, which are ligands for "I-E related" V beta, V beta 5, V beta 11, and V beta 12. Although all V beta associated with the recognition of the conventional Mls determinants are, in general, uniformly deleted in those animals expressing relevant Mls, expression of Mlsf-related V beta reveals various deletion patterns among different strains. Here we describe extensive genetic studies to evaluate the relationship among the self-Ag responsible for clonal deletion of T cells bearing Mlsf-related V beta by using antibodies specific for TCR V beta chain. In addition, a panel of T cell clones specific for the Mlsf determinant were generated and employed to analyze the determinant specificity, which is recognized by Mlsf-reactive T cells in vitro as well as the role of class II molecules in T cell recognition of the Mlsf determinants. The results of these two independent approaches provide evidence that the Mlsf system is composed of a set of gene products that reveal a unique polymorphism in the induction of clonal deletion in vivo and in T cell activation in vitro. One of these gene products causes almost complete deletion of the self-Mlsf reactive T cell repertoire in vivo and elicits a strong proliferative response to Mlsf-specific T cell clones. Expression of the other gene products results in the clonal deletion of only part of the Mlsf-reactive T cell repertoire. Furthermore, the response pattern of Mlsf-specific clones to intra-MHC recombinant inbred strains and the inhibition pattern of these clones by anti-class II antibody suggested that although expression of the I-E molecule is essential for T cell recognition of Mlsf determinants, the A beta gene may also contribute to the efficient presentation of Mlsf determinants by forming unique class II E alpha A beta molecules.

Animals↗
PubMed1992

Characterization of the Mlsf system. II. Identification of mouse mammary tumor virus proviruses involved in the clonal deletion of self-Mlsf-reactive T cells.

The genetic linkage of loci encoding stimulatory Mlsa and Mlsc determinants with proviruses of mouse mammary tumour viruses (MMTV) has been shown. We previously have reported that the ligand(s) for V beta 5, V beta 11, and V beta 12 behaves as a novel minor lymphocyte-stimulating (Mls) determinant(s), Mlsf, to induce the strong proliferation of unprimed T cells, and that this ligand(s) also functions as a self-Ag for the clonal deletion of self-reactive T cells. In the accompanying paper (Part I), a unique polymorphism characteristic of the Mlsf gene product is presented. In order to determine the genetic basis for this novel Mls system, we examined the progeny of multiple genetic crosses to identify the MMTV proviral loci involved in the clonal deletion of self-Mlsf-reactive T cells. Results from these investigations indicated that at least three known MMTV proviruses, Mtv-8, Mtv-9, and Mtv-11 are involved in the expression of Mlsf gene products. Presence of Mtv-9 results in the complete deletion of V beta 5, V beta 11, and V beta 12; Mtv-8 is associated with the complete deletion of V beta 12, but only a partial deletion of V beta 11 (primarily CD4-positive T cell subset) with little or no deletion of V beta 5; and Mtv-11 induces the complete deletion of V beta 11 and V beta 12, but no deletion of V beta 5. Given the significant sequence homology in the C-terminal portion of the open reading frame (ORF) region among these three MMTV and the almost equivalent effect of these three MMTV provirus upon the V beta 12 repertoire, their apparent hierarchic effect upon the V beta 5 and V beta 11 repertoires suggests that affinity differences in recognition of the same determinant by different TCR V beta may play a significant role in the clonal deletion of self-reactive T cells.

Animals↗
PubMed1992

Expression of Mls determinants in mice exhibiting the severe combined immunodeficiency (scid) mutation or X-linked immunodeficiency (xid) defect.

While Ig+ B cells appear to be the principal cell type expressing immunogenic minor lymphocyte stimulatory (Mls) determinants, both T cells and B cells are capable of mediating deletion of developing Mls-reactive thymocytes. In addition, levels of mouse mammary tumor proviral transcripts are increased after B or T cell stimulation, and expression of functional Mls determinants is augmented by activation of B cells. These findings suggest Mls determinants are present on B and T lymphocytes, and that activation of B and T cells augments Mls expression. In the present study, we wished to determine whether B and T cells were required for expression of Mls determinants by examining mice with severe combined immunodeficiency (SCID) containing no detectable Ig+ B cells or TCR+ T cells, as well as animals that expressed the X-linked immunodeficiency (xid) defect and lacked a subset of mature B cells. We found Mlsa-reactive V beta 6hi T cells were deleted from thymi of male (CBA/NxAKR/J)F1 xid mice, and that spleen cells from these animals stimulated anti-Mlsa mixed lymphocyte responses by unprimed B10.BR spleen T cells. In addition, Mlsc-reactive V beta 3hi AKR/J thymocytes and spleen T cells were deleted in AKR/J----SCID bone marrow chimeras, and spleen cells from SCID mice stimulated proliferation by an Mlsc-specific T cell clone. These results demonstrate that both xid mice and SCID animals express Mls determinants that mediate deletion of developing, Mls-responsive thymocytes and stimulate proliferation of mature, Mls-reactive T cells. Hence, mature B cells and T cells are not essential for Mls expression.

Animals↗
PubMed1992

T cell receptor-mediated recognition of self-ligand induces signaling in immature thymocytes before negative selection.

Shaping of the T cell repertoire by selection during intrathymic maturation involves T cell receptor (TCR) recognition of major histocompatibility complex/self-antigen complexes. In this communication, we studied the ability of minor lymphocyte stimulating (Mls) determinants to act as self-tolerogens in the selection of the T cell repertoire. We demonstrate that unprimed T cells from normal as well as TCR transgenic mice form Mls-specific conjugates with antigen-presenting cells, and that this TCR-ligand interaction leads to elevation of intercellular Ca2+ ([Ca2+]i). Peripheral T cells from TCR transgenic mice expressing receptors specific for self-Mls antigen show no reactivities to Mlsa. However, a proportion of immature thymocytes from these mice show specific binding and strong [Ca2+]i elevation in response to self-antigen-presenting cells, although these thymocytes do not proliferate. This self-reactivity of thymocytes is inhibited by antibodies specific for TCR, CD4, CD8, class II molecules, lymphocyte function-associated antigen 1, and intercellular adhesion molecule 1. These results demonstrate for the first time that before thymic negative selection, immature T cells can specifically interact with cells bearing self-antigen, and suggest that the resulting TCR-dependent signal transduction events provide a basis for negative selection of self-reactive T cells.

Animals↗
PubMed1992

Correlation of loss of alleles on the short arms of chromosomes 11 and 17 with metastasis of primary breast cancer to lymph nodes.

To examine the role of loss of heterozygosity (LOH) during tumor development and/or progression, we looked for correlations between metastasis of breast cancer to a regional lymph node(s) and LOH of chromosomal arms 11p, 13q, 16q, 17p, and 17q, where frequent losses in primary tumors have been detected. No correlation between lymph node metastasis and LOH of chromosomes 13q, 16q, or 17q was observed. However, tumors showing LOH of chromosomes 11p (chi 2 = 10.82, P less than 0.01) and 17p (chi 2 = 6.78, P less than 0.01) revealed a significantly higher incidence of metastasis to a regional lymph node(s) than tumors without LOH on these chromosomal arms. Furthermore, only four of 30 (13%) patients with tumors that retained both 11p and 17p had metastasis to a regional lymph node(s), compared with 24 of 32 (75%) patients with tumors that had lost both 11p and 17p. Analysis of LOH with markers on chromosomes 11p and 17p in a large number of tumors indicated that the peritelomeric region of each of these chromosomal arms contains a tumor suppressor gene that may be associated with tumor progression, particularly metastasis to a regional lymph node(s).

Alleles↗
PubMed1992

Recombinant human erythropoietin for autologous blood donation: effects on perioperative red-blood-cell and serum erythropoietin production.

To speed collection of blood for autologous transfusion during elective surgery, patients may be given recombinant human erythropoietin (r-HuEPO). In a controlled trial, we evaluated the effects of r-HuEPO on perioperative red-blood-cell and serum erythropoietin (s-EPO) production in patients donating blood before elective orthopaedic surgery. Patients were assigned randomly to receive no r-HuEPO (12 patients), or 3000 U (4), 6000 U (5), or 9000 U (4) of r-HuEPO intravenously twice a week from the time of the first blood donation. All patients received iron sulphate. 1200 ml blood was collected from each patient in three weekly donations of 400 ml. The 3000, 6000, and 9000 U treatment groups produced 284, 350, and 383 ml, respectively, of red cells during donation, and the untreated controls produced 211 ml. s-EPO concentrations were within the normal range during donation. After surgery, s-EPO concentrations peaked on postoperative day 1 in untreated patients and on day 7 in treated patients; therefore, r-HuEPO may suppress endogenous erythropoietin secretion. Although administration of r-HuEPO increases production of red blood cells, the preoperative anaemia induced by repeated phlebotomy without r-HuEPO may accelerate the postoperative secretion of endogenous erythropoietin.

Adolescent↗
PubMed1992

A trial of adjuvant chemoimmunotherapy with mitomycin C and OK-432 for stage III gastric carcinoma.

We previously found that the ability to generate cytotoxic cells induced by in vitro activation of peripheral blood mononuclear cells (PBM) with OK-432, a bacterial immunopotentiator, was markedly increased following intravenous administration of a single dose of mitomycin C (MMC) in cancer patients. On the basis of this clinical finding, we designed a treatment regimen that consisted of MMC 12 mg/m2 intravenously on day 1 and OK-432 5 Klinische Einheit (KE) intradermally on days 6, 8, and 11, when the generation of OK-432 activated killer cells had been shown to be significantly augmented. Then, it was followed by long-term tegafur. Fifteen patients with stage III gastric carcinoma who had undergone curative resection were treated with the above regimen. The survival of these patients was significantly better than that of 26 comparable stage III patients concurrently treated with MMC 12 mg/m2 alone, followed by long-term tegafur (P less than 0.01). The results indicate that OK-432 combined with MMC may be effective against stage III gastric carcinoma, when these agents are used probably in an appropriate combination.

Carcinoma↗
PubMed1992

Amplitude analysis of stress technetium-99m methoxy isobutylisonitrile images in coronary artery disease.

To determine the role of rest and stress gated technetium-99m methoxyisobutylisonitrile (sestamibi), in the detection of coronary artery disease, routine Fourier analysis of these images was performed with the best septal left anterior oblique (LAO) position of 20 patients (17 men, 3 women; aged 40-75 years) who also underwent rest or redistribution/stress single photon emission tomography (SPET) (99mTc-sestamibi and Thallium-201), gated blood pool imaging and coronary angiogram. There were 6 patients with single-vessel disease, 6 with two-vessel disease, 4 with three-vessel disease, 2 with coronary spasms, 1 with a patent graft and 1 with anginal episodes but a normal angiogram result. Three normal volunteers (2 women, 1 man; aged 24-26 years) also had rest and stress gated blood pool as well as rest and stress gated 99mTc-sestamibi imaging. Rest and stress 99mTc-sestamibi amplitude and phase images depicted regional myocardial wall shortening from the outer layer of the myocardium to the center of the left ventricle as follows: a high amplitude halo of maximal negative count rate variation; a circular thinner halo of negligible amplitude; a central region of maximal positive count rate variation, as the images evolved from end-diastole to end-systole. Similar patterns with regional differences represented abnormal myocardial wall shortening. 99mTc-sestamibi and 201Tl SPET images were in agreement in 90% of the patients and 92% of myocardial regions. 201Tl SPET detected 83% of angiographically proven lesions, as compared with 80% for 99mTc-setamibi SPET and 80% for the amplitude images. The amplitude images demonstrated a larger number of other abnormalities not predicted on the angiogram, probably because they were able to detect regions with a potential for flow improvement and transient regional wall shortening abnormalities.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

The relationship of estrogen receptor status to DNA ploidy in breast cancer.

The relationship of estrogen receptor (ER) status to DNA ploidy was investigated in 121 patients with breast cancer who underwent surgery. Lymph node status was evaluated histologically and ER levels were determined by the dextran-coated charcoal method, with a level of 3 fmol/mg.protein being considered positive. Flow cytometric DNA content was analyzed using paraffin-embedded tissue blocks. Sixty-three percent of the specimens were ER+, while 37 percent were negative. Sixty-one patients (50.4 percent) were diploid and 60 aneuploid. A statistically significant correlation between the ER positivity rate and diploid DNA was found. Higher ER levels were seen in the postmenopausal patients with diploid tumors than in those with aneuploid tumors and there was a significant tendency for ER levels to be higher in the diploid tumors. Nodal status was not correlated with ER positivity or ploidy pattern. The present results indicate that ER levels are correlated with DNA ploidy, and reflect the degree of functional differentiation.

Biomarkers, Tumor↗
PubMed1992

Correlation of eosinophilia with clinical response in patients with advanced carcinoma treated with low-dose recombinant interleukin-2 and mitomycin C.

On the basis of our clinical findings that the ability of cancer patients to generate lymphokine-activated killer cells became markedly augmented after mitomycin C administration, we designed a treatment regimen comprising mitomycin C 12 mg/m2, i.v. on day 1 and recombinant interleukin-2 700 U/m2 (8000 IU/kg), i.v. every 12 h from day 4 through day 8. The treatment course was repeated at almost 7-day intervals. Altogether 33 patients with advanced carcinoma, including mainly gastrointestinal carcinoma, were treated with this regimen. Of these, 10 had a partial response (PR) and 4 had a minor response (MR). Since eosinophil counts peaked 1 day after either the first or second course of the therapy, the posttreatment values were compared to each pretreatment level, with regard to the clinical antitumor response to this treatment. When patients who showed PR were defined as responders, absolute eosinophil counts and the percentage of eosinophils in responders after both the first and second courses of the therapy were significantly greater than each pretreatment value or the posttreatment level in nonresponders. Further, these findings were almost identical, when both PR and MR were considered to be a true remission and therefore patients who exhibited PR or MR were defined as responders, although the difference between posttreatment levels of eosinophils in responders and nonresponders was not significant at the second course. These results indicate that eosinophilia induced by this treatment correlates with the clinical response to this therapy.

Aged↗
PubMed1992

Evaluation of an improved dot-immunobinding assay for carcinoembryonic antigen determination in nipple discharge in early breast cancer: results of a multicenter study.

We have previously reported carcinoembryonic antigen (CEA) measurement in nipple discharge to be a useful adjunct in the diagnosis of non-palpable breast cancer. We have now developed a "microdot-immunobinding assay" using a specially constructed device to screen efficiently large numbers of patients with nipple discharge for non-palpable breast cancer. The method is as follows: a sample of nipple discharge is placed on a solid phase monoclonal anti-CEA antibody and, if CEA is present in the discharge, it will be detected by a second monoclonal anti-CEA antibody conjugated with alkaline phosphatase. The use of bromochloroindolyl phosphate as a chromogen results in a stable color reaction that can be semiquantitatively analyzed with the naked eye. CEA levels determined by this microdot assay correlated well with those determined using the earlier Elmotec assay. To determine the accuracy of the method, a collaborative study involving 11 institutes in Japan was organized. The CEA levels in nipple discharges from 77 patients undergoing surgery, 44 of whom were diagnosed as having breast cancer, were assayed. The results were that 17 of the 23 patients with palpable breast cancer, and 16 of the 21 patients with non-palpable breast cancer exhibited CEA values > 400 ng/ml, a cut-off value determined in a previous study. The overall accuracy (78%) of this test for diagnosing non-palpable breast cancer was higher than that obtained from ductography or cytology. The system may thus be of use in the screening of early breast cancer.

Breast Neoplasms↗
PubMed1992

T cell recognition of Mls-like superantigens: analysis of TCR requirements, superantigenic ligands, and signal transduction.

Mls-like endogenous superantigens have been reported to be unique, differing from conventional antigens in the T cell receptor (TCR) requirements for their recognition, in the signal transduction events which they elicit in T cells, and in the identity of the stimulatory ligand. This review describes recent findings indicating that TCR V alpha as well as V beta products play a role in Mls recognition. Data are also summarized which indicate that T cell recognition of Mls leads to increased intracellular [Ca2+] and phosphatidyl inosotol hydrolysis. Finally, genetic linkage between mouse mammary tumor virus (MMTV) proviruses and endogenous superantigens is analyzed, and the possible role of non-MMTV products is examined.

Animals↗
PubMed1992

[Long-term results in 1,400 patients with coronary artery bypass grafting: saphenous vein vs arterial grafts].

To analyze and compare the effects of saphenous vein grafts (SVG) and arterial grafts (AG) on the long-term results of the coronary artery bypass grafting (CABG), retrospective nonrandomized studies were performed in 1,400 consecutive patients with CABG in terms of reoperation, postoperative transluminal coronary angioplasty (PTCA) to the grafts, actuarial survival rate, and cumulative event free rate. AG was used frequently in recent cases in which more diffuse and multiple vessel disease were encountered. No statistically significant differences were noted in any of the reoperation free rate, actuarial survival rate, success rate of the PTCA, and cumulative event free rate between SVG and AG, because the long-term results of the SVG was apparently better than reported Caucasian's long-term results, while those of the AG were as good as Caucasian's. Reoperation and PTCA for the AG were performed less than one year after the CABG in most cases and restenosis after the PTCA was rare. In contrast, those for the SVG were mainly done late postoperative period, and the incidence of the restenosis after the PTCA was very high. These results indicated that the main cause of the graft failure in the AG was technic-related, and that of the SVG was graft's atherosclerosis. We conclude from this study that AG should be indicated more extensively than SVG, but proper indication and application of the AG in various situations and technical improvement to avoid stenosis at anastomosis are important to improve the long-term results of the CABG.

Adolescent↗
PubMed1992

[Multicenter cooperative study of pre- and post-operative adjuvant chemotherapy in the treatment of colorectal cancer. North Kyushu Co-operative Study Group for Cancer Chemotherapy].

The usefulness of pre- and post-operative adjuvant chemotherapy in colorectal cancer patients was studied by the North Kyushu Co-operative Study Group for Cancer Chemotherapy (21 participating institutions). Comparisons were made among group I given a tegafur suppository preoperatively+tegafur oral preparation postoperatively, group II given a tegafur suppository preoperatively+UFT oral preparation postoperatively and group III given a tegafur oral preparation postoperatively. No differences were seen in the incidence of postoperative complications depending on whether or not tegafur suppositories were administered preoperatively. There were also no differences in the symptom or incidence of side effects due to postoperative administration of tegafur or UFT. In a study of 5-FU concentration in the lymph nodes due to preoperative tegafur administration and recurrences, the concentration of 5-FU was significantly higher in the lymph nodes of cases without recurrences than in those with recurrences, and it was suggested that a relation exists between the concentration of agent and recurrences. The concentration of 5-FU in the lymph nodes of Dukes B patients was significantly higher in cases without recurrences than in those with recurrences. The non-recurrence rate (healthy rate) was better in the group given UFT postoperatively than in that administered tegafur postoperatively although the difference was not significant.

Administration, Oral↗
PubMed1992

[An experimental study of determining the appropriate frequency of radiofrequency catheter ablation in vitro and in vivo for ventricular tachycardias].

The purpose of this study was to examine the appropriate frequency of radiofrequency catheter ablation (RFA) for ventricular tachycardia. Radiofrequency energy generated by a device in which the frequency could be changed, was delivered from an electrode catheter with an electrode tip-width of 4 mm. RFA was performed for 10 seconds with 20W (50V x 0.4A) using 7 different frequencies from 10 to 500 kHz on ventricular myocardium in vitro and in anesthetized dogs. The ablated lesion was significantly larger with RFA of 200-300 kHz in both surface area and depth (p less than 0.05). The appearance of ventricular arrhythmia during RFA increased as the frequency decreased, and one dog applied with RFA of 100 kHz had spontaneous ventricular fibrillation resulting in death. All dogs with frequency less than 100 kHz had a muscle cramp during RFA. We conclude that appropriate frequency seems to be 200-300 kHz to obtain a large ablated lesion, and a frequency higher than 300 kHz seems suitable to avoid arrhythmia. We also conclude that a frequency under 100 kHz should not be used.

Animals↗
PubMed1992

[Phase I study of NK 622 (toremifene citrate)].

A phase I study of NK 622 (toremifene citrate), a novel antiestrogen, was conducted in female patients with cancer. Patients received a single oral dosing or daily once oral dosing for five consecutive days. Any adverse effects were not experienced in the single dosing of 40 or 60 mg of NK 622. In the daily administration of 10, 20, 40, 60, 120, 240 and 480 mg/day, one of three patients who received 20 mg/day experienced grade 1 anorexia, three of four patients received 240 mg/day experienced adverse effects: Grade 1 leukopenia in one patient, Grade 1 general hot flush in one patient, and Grade 1 nausea, hot flush in the face and vertigo, Grade 2 anorexia, fatigue, dull headache and general hot flush in another one patient. These symptoms recovered to normal levels after treatment. Serum hormone levels were examined in postmenopausal patients, and a significant increase of the sex hormone binding globulin level was observed in the patients received 120 and 240 mg/day doses. Serum levels of NK 622 determined as free base (TOR) reached the peak levels in 2 to 4 hours after administration on the 1st and 5th day in daily treatment, while a metabolite N-demethyltoremifene (TOR-1) reached the peak level in 4 to 170 hours. Maximum serum levels and area under the concentration versus time curves of TOR and TOR-1 increased dose-dependently. These values also increased by repetition of the treatment. Half-lives of TOR and TOR-1 in serum ranged in 74.5 to 148.9 hours and 154.1 to 653.1 hours, respectively. From these results, it was concluded that safety and efficacy of NK 622 should be assessed by using 240 mg or less doses in clinical phase II studies where breast cancer patients received long term treatment with NK 622.

Administration, Oral↗