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Biomedical subjects

R Abe

Publications and source records attributed to R Abe.

At least 109 records · Page 6Linked to original sources
PubMed1998

Low doses of lipopolysaccharide upregulate acinar cell apoptosis in cerulein pancreatitis.

We have reported previously that administration of a sublethal low dose of lipopolysaccharide (LPS; 50 microg/kg) prior to the induction of cerulein (Cn) pancreatitis mitigates the pathological course. To clarify the mechanism, we examined apoptosis in the pancreas using the same model. Apoptosis was evaluated by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) and transitional electron microscopy. LPS pretreatment at a dose of 50 microg/kg increased remarkably the incidence of acinar cell apoptosis in Cn pancreatitis rats compared with LPS-untreated Cn pancreatitis rats. Apoptosis was observed selectively in acinar cells but was not shown in endocrine cells or ductal epithelial cells. Infiltration of inflammatory cells was scarcely observed. These acinar cells showed the characteristic morphological features of apoptosis by electron microscopy. Administration of LPS at a dose of 50 microg/kg alone caused acinar cell apoptosis but the incidence was much lower than that in the LPS-pretreated Cn pancreatitis rats. The TUNEL labeling was significantly increased depending on the dose of LPS and on the interval between the administration of LPS and that of Cn. These results suggest that the pathological features of acute pancreatitis might be modified by the presence of nonfatal endotoxemia through the induction of acinar cell apoptosis.

Animals↗
PubMed1998

The functional role of B7 molecules on the induction of thymocyte activation and apoptosis.

To evaluate the role of B7 on thymocyte activation and apoptosis, we took advantage of TCR transgenic mice in which the majority of thymocytes express a uniform TCR that is specific for ovalbumin. We also prepared Chinese hamster ovary (CHO) cells expressing B7 and appropriate class II molecules. We found that the apoptosis of double-positive thymocytes by TCR-mediated signaling, which presumably represents negative selection, requires a costimulatory signal provided by B7-1 or B7-2. The requirement of B7-1 costimulation for the apoptosis of thymocytes does not change in either low or high antigenic peptide loading. We also demonstrated that two signals through TCR and CD28 augmented the proliferation of thymocytes, and the requirement of CD28-mediated signal by B7-1 or B7-2 for thymocyte proliferation became less evident when high doses of antigenic peptide were loaded, indicating that the intensity of TCR-mediated signal determines the requirement of B7-mediated second signal for thymocyte proliferation.

Animals↗
PubMed1998

[Phase I study of TAT-59 (a new antiestrogen) in breast cancer. TAT-59 Study Group].

Phase I study of TAT-59 (Miproxifen), an antiestrogen developed in Japan for breast cancer, was conducted with the collaboration of 12 hospitals. A single dose of 1.25, 5, 10, 20, 40 and 80 mg, or 5 consecutive daily doses of 1.25, 5, 10, 20 and 40 mg/day, were given orally. After single dosing, no clinical adverse effects were found. Decrease of serum Na, Cl, Ca level and increase of serum LDH level were observed in one patient after a single dose of 5 mg of TAT. An increase in the serum LDH level was also observed in one patient after a single dose in the of 10 mg of TAT. An increase in the serum LDH level and total bilirubin, increase of eosinophil, K and milky serum were also observed in one patient after a single dose of 40 mg of TAT, respectively. All of these abnormal values returned to the normal level within 26 days after final administration of TAT. No adverse clinical findings nor abnormal laboratory findings were observed after consecutive administration of TAT. After postprandial single dosing, the time to reach the maximum serum concentration (Tmax) of DP-TAT, dephosphorylated metabolite of TAT, and its demethylated metabolite, DMDP, ranged from 5.0 to 7.3 hr and from 17.0 to 42.8 hr, respectively. The maximum serum concentration (Cmax) and AUC of DP and DMDP elevated in a dose-dependent manner. T1/2 of DP and DMDP ranged from 24.2 to 41.5, and from 91.9 to 214.7 hr, respectively. There were no significant differences between pharmacokinetics of TAT before and after food intake. Based on the above results, we concluded that a Phase II study should be conducted to evaluate the efficacy, safety and optimal dose of TAT.

Administration, Oral↗
PubMed1998

[Correlation between apoptotic index, bcl-2 protein expression and progression and prognosis in breast carcinoma].

Apoptosis is considered to play a critical role in tumorigenesis. It has been shown that apoptosis is controlled by both pro-oncogenes bcl-2, c-myc and tumor-suppressor genes p53. We determined the apoptotic index (AI) on light microscopy and detected immunohistochemically the expression of bcl-2 and p53 in patients with breast cancer. The correlations between AI and clinicopathological factors, bcl-2 and p53 were also analyzed. Our results showed that bcl-2 expression was down-regulated in the process from normal breast epithelial cells to intraductal carcinoma and from intraductal carcinoma to invasive carcinoma. We failed to detect p53 protein in normal breast epithelial cells, and p53 positivity was 24% and 30% in intraductal and invasive cancer tissues, respectively. Moreover, AI was significantly associated with histological grade, mitotic index, and bcl-2 and p53 expression. In univariate analyses, lower AI and bcl-2 expression was significantly predictive of a better prognosis for both disease-free survival and overall survival. These results suggest that apoptosis and apoptosis-related gene (bcl-2, p53) are related to progression and prognosis in breast cancer.

Adult↗
PubMed1998

[Analysis of microsatellite alteration in colorectal cancer].

We investigated the possible correlation between the microsatellite alterations (replication error: RER, and loss of heterozygosity: LOH) and clinicopathologic factors and survival in colorectal cancer. A total of 78 colorectal cancers was examined for microsatellite alteration at three microsatellite loci containing D2S123, D18S58 and C117-703. RER is considered positive when at least one microsatellite locus is detected. RER was positive in 28.2%, and the respective positivity was 12.8%, 15.3% and 11.5%. The positivity of LOH was 6.4%, 10.3% and 19.2%, in that order. RER-positive cancers were more significantly found in the proximal colon than the distal colorectum. Node-negative colorectal cancers were more noted in RER (+)-positive cancers. Multivariate analysis showed that LOH in D18S58 locus and RER in CI17-703 locus were independent prognostic factors.

Aged↗
PubMed1998

[Telomerase activity in colorectal cancer--a semi-quantitative procedure].

Telomerase maintains telomere at the end of chromosome and stabilizes chromosome. It is thought to have important roles in cancer progression and cell immortality. We evaluated the role of telomerase expression in colorectal carcinogenesis. Materials included 13 colonic adenomas, 9 early colorectal cancers, 32 advanced colorectal cancers, 5 metastatic tumors, and 30 non-cancerous colon mucosas. The telomerase activity was analyzed using TRAP-eze (Oncor Inc.) for a semi-quantitative method. The positive rate of telomerase activity was 13.3% in non-cancerous colonic mucosa, 15.4% in colonic adenomas, 77.8% in early colorectal cancers, 93.8% in advanced colorectal cancers, and 100% in metastatic tumors; the mean value was 18.0, 29.9, 65.8, 97.0 and 161.3. The correlation between telomerase activity and tumor size, histologic type, or depth of invasion was noted. Sensitivity, specificity and accuracy were on the order of 89%, 98% and 93% at the cut-off level as two times the mean value of non-cancerous mucosa. Telomerase had an important role in carcinogenesis, and progression of colorectal cancer, and it was suggested to be useful for a tumor marker.

Adenocarcinoma↗
PubMed1998

[Nuclear DNA content of parathyroid tumor with hyperparathyroidism].

It is not easy to make a differential diagnosis among adenoma, hyperplasia and carcinoma with hyperparathyroidism (HPT). We investigated the flowcytometric nuclear DNA content and analysis of cell cycle for 29 patients (39 parathyroid glands) with HPT and 16 normal parathyroid glands at the Department of Surgery II, Fukushima Medical College. Flowcytometry was performed by EPICS 751 flowcytometer (Coulter Co.) in paraffin-embedded tissue. Each fraction of cell cycle was analyzed by the PARAI software program. All controls and secondary hyperplasia showed diploid. Aneuploid pattern was found in 27.6% of all HPTs (50% of carcinomas, 30% of adenomas and 6.7% of primary hyperplasia). The S phase fraction (SPF) and proliferative index (PI) were increased in carcinomas. PIs, especially the fraction of G2M, in primary and secondary hyperplasias were more decreased than those in normal controls and adenomas. Preoperative intact-PTH, c-PTH, ionized calcium, ALP and weight of parathyroid gland had no significant correlation with DNA ploidy, DNA index and SPF. PI had tended to correlate only with the weight of parathyroid gland. When DNA content shows aneuploid, high SPF or PI in parathyroid adenoma and hyperplasia, strict follow-up is required because of the malignant potential. If G2M or PI is lower, we should pay attention not to leave any remaining glands in parathyroidectomy in the light of hyperplasia.

Adenoma↗
PubMed1998

Clinical characteristics of breast cancer patients with family history.

This study was conducted to acquire information as to the clinicopathological characteristics of breast cancer patients with family history. Of 583 patients with breast cancer, 60 (10.3%) had family history in at least one relative within the second-degree. The affected family member was most frequently a sister (43%), followed by the mother (23%) and an aunt (20%). Comparison of the data for the patients between with and without family history revealed no significant differences for any of mean age, menopausal status, histological type, histological staging, and estrogen receptor status. Although the sample size was small, neither the survival rate nor the bilaterality of disease was influenced by the family history of breast cancer.

Adult↗
PubMed1998

Mesenteric venous thrombosis: a case report.

We describe herein a 41-year-old man who complained of abdominal pain. He underwent surgery, and the diagnosis of mesenteric venous thrombosis was made. The small intestine, mainly the jejunum, presented necrosis on laparotomy, and a 155-cm long segment of it was successfully resected. Anticoagulant therapy was initiated postoperatively, and he is well at present.

Adult↗
PubMed1997

Clinicopathological Features of Hereditary Breast Cancer.

The possible role of germline mutations of BRCA1 and BRCA2 as causative agents of familial breast cancer was assessed. Their possible involvement in the carcinogenesis of hereditary breast cancer was investigated using 63 clinically suspect families. Twenty-one lineages (33.3%) had mutations in one of the two BRCA genes. This relatively low incidence suggested that germline mutations in unknown genes are involved in the carcinogenesis of hereditary breast cancer in the Japanese population. However, the clinicopathological features characteristic of hereditary breast cancer, such as early disease onset, a high incidence of bilateral breast cancer, and a high incidence of multiple primary carcinomas in other organs were confirmed in the present study.

Journal Article↗
PubMed1997

T cell receptor (TCR)-induced death of immature CD4+CD8+ thymocytes by two distinct mechanisms differing in their requirement for CD28 costimulation: implications for negative selection in the thymus.

Negative selection is the process by which the developing lymphocyte receptor repertoire rids itself of autoreactive specificities. One mechanism of negative selection in developing T cells is the induction of apoptosis in immature CD4+CD8+ (DP) thymocytes, referred to as clonal deletion. Clonal deletion is necessarily T cell receptor (TCR) specific, but TCR signals alone are not lethal to purified DP thymocytes. Here, we identify two distinct mechanisms by which TCR-specific death of DP thymocytes can be induced. One mechanism requires simultaneous TCR and costimulatory signals initiated by CD28. The other mechanism is initiated by TCR signals in the absence of simultaneous costimulatory signals and is mediated by subsequent interaction with antigen-presenting cells. We propose that these mechanisms represent two distinct clonal deletion strategies that are differentially implemented during development depending on whether immature thymocytes encounter antigen in the thymic cortex or thymic medulla.

Animals↗
PubMed1997

Macrophage migration inhibitory factor is an essential immunoregulatory cytokine in atopic dermatitis.

Macrophage migration inhibitory factor (MIF) is one of the immunoregulatory cytokines involved in T-cell activation and delayed-type hypersensitivity. To elucidate involvement of this cytokine in the pathogenesis of atopic dermatitis (AD), we examined serum MIF concentrations of patients with AD and non-atopic normal healthy individuals. The mean serum MIF concentration of the AD patients (n = 36) was 36.4 +/- 3.7 ng/ml (mean +/- SEM), whereas that of the non-atopic dermatitis patients (n = 17) or healthy individuals (n = 61) were 13.1 +/- 1.8 or 6.5 +/- 0.45 ng/ml, respectively. Accordingly, immunohistochemistry of the inflammatory skin lesion of an AD patient demonstrated that MIF protein was diffusely expressed throughout the whole epidermal layer. After 4-week steroid ointment treatment, the MIF concentration decreased as clinical symptoms improved. The serum level of TNF-alpha was also decreased in parallel with that of MIF. Considering the T-cell dysfunction and disordered cytokine-network reported in AD, it was strongly suggested that MIF was a critical protein for immunoregulation in the pathophysiological mechanism of AD. In this context, MIF may become a useful laboratory parameter to comprehend the clinical course of the disease.

Adjuvants, Immunologic↗
PubMed1997

CD9-mediated costimulation of TCR-triggered naive T cells leads to activation followed by apoptosis.

The induction of full activation or death in TCR-triggered T cells depends largely on whether appropriate costimulatory signals are provided. In this study, we show that the costimulation of CD9 on naive T cells during TCR stimulation results in transient, albeit potent, activation followed by apoptosis, rather than full activation. Anti-CD9 mAb synergized with suboptimal doses of anti-CD3 mAb in inducing T cell activation. [3H]TdR incorporation determined 2 days after CD9 costimulation was as potent as that induced by CD28 costimulation. In contrast to progressive T cell proliferation induced by CD28 costimulation, CD9 costimulation led to the induction of apoptosis of once-activated T cells. Although IL-2R expression was induced significantly earlier and to a greater degree after CD9 costimulation than after CD28 costimulation, CD9 costimulation only transiently produced a small amount of IL-2 and induced apparently low levels of bcl-xL compared with those observed in CD28 costimulation. Addition of rIL-2 to cultures of CD9 costimulation induced strikingly enhanced expression of bcl proteins, especially of bcl-xL, and protected TCR-stimulated T cells from apoptosis. These data indicate that CD9-mediated costimulation of TCR-triggered naive T cells leads to activation followed by apoptosis as the result of failure to generate a positive signal for sufficient levels of IL-2 production.

Adjuvants, Immunologic↗
PubMed1997

Germ-line mutation of the hMSH6/GTBP gene in an atypical hereditary nonpolyposis colorectal cancer kindred.

A germ-line mutation of hMSH6 (also called GTBP) was found in a hereditary nonpolyposis colorectal cancer (HNPCC)-like patient in whom germ-line mutations of hMSH2, hMSH3, or hMLH1 had not been detected. The patient had rectal cancer and two colon adenomas at 62 years of age and a weak family history of gastrointestinal tumors, indicating atypical HNPCC. Somatic mutations of hMSH6 were observed in three colorectal tumors from the patient, indicating two-hit inactivation. Microsatellite instabilities at mononucleotide repeats were detected in all three tumors. These data suggest that hMSH6 is responsible for tumorigenesis in atypical HNPCC.

Adenoma↗
PubMed1997

Meta-Analysis of the Second Collaborative Study of Adjuvant Chemoendocrine Therapy for Breast Cancer (ACETBC) in Patients with Stage II, Estrogen-Receptor-Positive Breast Cancer.

The second 5-year study of postoperative adjuvant therapy in patients with breast cancer between 1985 and 1988 was performed by the Study Group for Adjuvant Chemoendocrine Therapy for Breast Canecr (ACETBC). This report describes the results of a meta-analysis of the outcome. A total of 3012 patients with stage II, estrogen-receptor-positive primary breast cancer who underwent radical surgery (total mastectomy with at least axillary dissection) were eligible for the analyses. On the day of surgery, all patients received 13 mg/m(2) of mitomycin C (MMC) intravenously. Patients were then given one of two adjuvant chemoendocrine therapies for 2 years:regimen A, consisting of tamoxifen citrate (TAM) 30 mg/day, or regimen B, consisting of TAM 30 mg/day plus tegafur (Futraful, FT)600 mg/day. The results from all eligible patients were included in a meta-analysis according to the method of Peto et al. The odds reduction rate was 12 +/-13% (log-rank test, P= 0.35)for the 5-year survival rate and 16 +/- 10% (log-rank test, P=0.093)for the 5-year non-recurrence rate. In terms of the 5-year non-recurrence rate. regimen B(with FT)yielded slightly, but not significantly, better results than regimen A. In addition, stratified analyses were carried out with respect to the 5-year non-recurrence rate. Regimen B(with FT)yielded significantly better results than regimen A in patients with four or more positive axillary nodes (log-rank test, P= 0.039) and yielded slightly, but not significantly, better results than regimen A in premenopausal patients (log-rank test, P= 0.079).

Journal Article↗
PubMed1997

Efficacy of Post-operative Adjuvant Therapy for Stage IIIa Berast Cancer: Futraful vs Futraful+Tamoxifen for ER-positive Patients and Futraful vs Futraful+Adriamycin for ER-negative Breast Cancer.

A multi-center, randomized controlled collaborative study was conducted in 310 institutions located thruoughout Japan for 3 years and 9 months from February 1985 until October 1988 to evaluate the efficacy of post-operative adjuvant therapy for patients who had previously undergone curative surgery for treatment of Stage III a breast cancer. Patients with estrogen receptor-positive [ ER(+)] breast cancer were treated with two types of regimens, ie, cyclophosphamide+adriamycin+fluorouracil (CAF; 2 cycles) +Futraful(FT) or CAF (2 cycles+FT+tamoxifen (TAM), and the clinical benefit of additional use of TAM was evaluated. Of the 509 ER(+) patients registered for the trial, 473 patients (92.9%) were eligible for evaluation.The 5-year survival rate was 77.2% for the CAF+FT group and 74.6% for the CAF+FT+TAM group, and the 5-year disease-free survival rate was 56.7% for the CAF+FT group and 59.2% for the CAF+FT+TAM group. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. Analyses by factor revealed that the 5-year disease-free rate for lymph node-negative patients in the CAF+FT+TAM group was significantly higher than that for the corresponding patients in the CAF+FT group. No differences were noted in the incidence of adverse reactions between the two treatment groups, other than an increase in LDH (the frequency of which was higher in the CAF+FT+TAM group than in the CAF+FT group). Patients with estrogen receptor-negative [ ER(-)]breast cancer were treated with two types of regimens, ie, CAF+FT or CAF+FT+adriamycin(ADR), and the clinical benefit of the combined use of intermittent doses of ADR was evaluated. Of the 514 ER(-) patients registered in the trial, 478(93.0%) were eligible for evaluation. The 5-year survival rate was 64.9% for the CAF+FT group and 63.0% for the CAF+FT+ADR group, and the 5-year disease-free survival rate was 59.2% for both CAF+FT and CAF+FT+ADR groups. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. There were no significant differences between these groups in analyses by nodal or menopausal status. The incidences of adverse reactions including anorexia, nausea/vomiting and alopecia were higher in the CAF+FT+ADR group than in the CAF+FT group.

Journal Article↗
PubMed1997

CD28 dependence of T cell differentiation to IL-4 production varies with the particular type 2 immune response.

T cell differentiation to effector cell function is required for the development of a type 2 immune response. The T cell surface molecule, CD28, is widely considered to be the principal costimulatory molecule involved in T cell differentiation to effector function, including IL-4 production, although this has been difficult to directly examine in vivo. We have studied in vivo differentiation to T cell effector function during two type 2 immune responses in CD28 knockout mice: the systemic immune response to goat anti-mouse IgD Ab and the mucosal immune response following oral inoculation with the nematode parasite, Heligmosomoides polygyrus. Our results show that in C57BL/6 CD28 knockout mice elevations in IL-4 gene expression and protein secretion are blocked during the immune response to goat anti-mouse IgD, and associated increases in serum IgG1 and IgE are also inhibited to untreated control levels. In marked contrast, T cell differentiation to IL-4 production is comparable in C57BL/6 CD28 -/- and CD28 +/+ H. polygyrus-inoculated mice, and elevations in both serum IgG1 and IgE levels occur. These results indicate that the specific kind of type 2 immune response determines whether T cell differentiation to IL-4 production is CD28 dependent.

Animals↗