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A Uchida

Publications and source records attributed to A Uchida.

355 records · Page 20Linked to original sources

Heritable translocation study in male mice with trimethyl phosphate.

Dominant lethal and heritable translocation studies were performed in male mice receiving a single intraperitoneal injection of trimethyl phosphate (TMP). The germ cell stage investigated was the spermatid. Methyl methanesulfonate (MMS) was used as a positive control in the latter study. A dominant lethal assay gave marked dose-dependent increases in early fetal deaths. Heritable translocations were detected at 1000 or 1500 mg of TMP/kg in F1 male progeny when screening for semi-sterility and cytogenetically analyzing the meiotic or mitotic chromosomes. Translocation induction was higher at the higher TMP dose (14.3%) than at the lower dose (5.3%) and the yield from the higher dose was similar to that induced by 50 mg of MMS/kg (11.0%). Most of the translocation carriers were semi-sterile or sterile. The data confirm conclusions from other dominant lethal studies showing TMP to be capable of causing chromosomal damage in mouse spermatids and show that certain types of damage result in heritable translocations.

Animals↗

Tenascin-C levels in pseudosynovial fluid of loose hip prostheses.

OBJECTIVE: Aseptic loosening is one of the most important problems that can occur after total hip arthroplasty (THA). In this study, we analysed levels of large tenascin-C (TN-C) variants and compared them in pseudosynovial fluid from patients with aseptic loosening after THA with those in synovial fluid from patients undergoing primary THA (control). METHODS: Pseudosynovial fluid samples (n = 24) were obtained by aspiration at the time of revision THA performed due to aseptic loosening. Synovial fluid samples (n = 12) were obtained by aspiration at the time of primary THA. Expression of TN-C splice variants was examined using immunoblotting. TN-C levels were measured using an enzyme-linked immunosorbent assay (ELISA) system that we developed previously. RESULTS: Western blotting showed the presence of large TN-C variants in pseudosynovial fluid of artificial joints with loosening. TN-C levels were approximately three times higher in pseudosynovial fluid of loose artificial joints (median 151.9 ng/mL) than in synovial fluid controls (median 50.1 ng/mL) (p = 0.035). CONCLUSION: Levels of TN-C including large variant subunits are elevated in pseudosynovial fluid of loose artificial joints, indicating that TN-C is a useful novel biochemical marker of loose hip prostheses.

Aged↗

Reduction of interleukin-2-receptor expression on retroplacental blood lymphocytes in human pregnancy.

Retroplacental blood lymphocytes (RPL) in human pregnancy were studied for proliferative response induced by recombinant interleukin-2 (rIL-2) and anti-Tac positive cells before and after PHA stimulation for 24 hr and compared with peripheral blood lymphocytes (PBL) of the same donor. Proliferation of RPL induced by IL-2 was significantly lower than that of PBL in all of six cases. In addition, flow cytometry analysis of IL-2 receptors (IL-2R) revealed that IL-2R expression of RPL after stimulation with PHA for 24 hr was significantly less than that of PBL in three of four cases and that RPL showed significantly fewer IL-2R than PBL even at resting state in one case. These results suggest that RPL seem likely to be composed of reduced numbers of lymphocytes bearing IL-2R of non-Tac protein and to have impaired capacity for the acquisition of high-affinity receptors for IL-2.

Female↗

Usefulness of argyrophilic nucleolar organizer staining for predicting prognosis of patients with recurrent soft tissue sarcoma.

Local recurrence of tumor is a common phenomenon in soft tissue sarcoma (STS) and may be accompanied by an increase in malignant potential. In the present study, an increase of proliferative activity in recurrent tumors compared to primary tumors was observed using a silver stain for nucleolar organizer regions (AgNOR), and its implication for predicting prognosis is assessed. 44 patients with STS showing local tumor recurrence were selected. Local recurrence was defined as new tumor growth more than 2 months after the initial surgery in the same region where the primary tumor occurred. All patients received surgery, followed in 11 patients by adjuvant radiotherapy and/or chemotherapy. The histologic subtype was malignant fibrous histiocytoma in 22 cases, synovial sarcoma in 5, leiomyosarcoma in 4, liposarcoma in 3, malignant schwannoma in 3, and others in 7. The interval between initial surgery and local recurrence ranged from 2 to 72 months. No patients changed from one histological subtype to another. Histological changes included an increase in mitosis, cellularity, and sclerosis in 43.2, 31.8, and 27.3%, respectively. The AgNOR count (mean +/- SD) in recurrent tumors (7.22 +/- 2.59) was significantly higher than that in primary tumors (5.58 +/- 2.28; p < 0.0057), clearly showing a tendency for an increase in proliferative activity during recurrence. The 5-year survival rate of patients with a marked increase (> 4) in AgNOR count (16.7%) was worse than with minor to moderate increases (60.0%; p < 0.02). Marked AgNOR increase was more frequently observed in the tumors located in the head and neck and retroperitoneum (40%) than in other sites (9%). Irrespective of the primary site of tumors, a marked AgNOR increase resulted in an unfavorable prognosis. Multivariate analysis of change in histologic factors including AgNOR, cellularity, mitotic counts, pleomorphism, myxoid change, necrosis, sclerosis, and tumor size showed that increase of AgNOR counts was significant (p < 0.05). The present findings suggest that AgNOR counts can be used as a prognostic factor in recurrent STS.

Adult↗

DNA ploidy pattern and cell cycle stage of tumor cells in soft-tissue sarcomas: clinical implications.

Staining and counting of argyrophilic nucleolar organizer region (AgNOR), segments of DNA with ribosomal genes, is useful for estimation of the proliferative activity in soft tissue sarcoma (STS). The precise role of AgNOR in STS, however, is still uncertain. In the present study, ploidy pattern and stage of cell cycle were analyzed in 151 cases of STS in the extremities and trunk, and their correlation with AgNOR and utility as independent prognostic factors were estimated. For this, microspectrophotometric and flow-cytometric analyses were done on paraffin-embedded material from 84 and 111 cases, respectively. Fifty-five percent cases showed an aneuploid pattern with a less favorable prognosis. The range of the DNA index and percentage of cells in S + G2M phase were 0.89-2.04 (mean +/- SD, 1.23 +/- 0.32) and 5.4-83.7% (mean +/- SD, 32.95 +/- 17.92), respectively. Tumors having less than 40% cells in the S + G2M phase showed a favorable prognosis compared to those over 40%. Both the ploidy pattern and stage of the cell cycle showed a good correlation with the AgNOR count: a high frequency of cases having aneuploidy and S + G2M phase in the AgNOR high count group. These findings provide a theoretical base for explaining the utility of AgNOR for the estimation of proliferative activity. In multivariate analysis, only AgNOR counts were a prognostic factor among histologic factors reflecting proliferative activity of tumors. The DNA ploidy pattern and the stage of the cell cycle was proved not to be an independent factor for prognosis.

Adolescent↗

Immunohistochemical detection of bcl-2 and p53 proteins and apoptosis in soft tissue sarcoma: their correlations with prognosis.

Information on prognostic factors is essential to establish appropriate therapeutic modalities for soft tissue sarcoma (STS). To evaluate the biological nature and prognostic factors of STS, p53 and bcl-2 expression was immunohistochemically studied on paraffin-embedded sections from 70 patients with STS in the extremities and trunk. In addition, the degree of apoptosis was examined by in situ end-labeling. Histologic diagnoses in these cases were malignant fibrous histiocytoma in 29 cases, liposarcoma in 11, synovial sarcoma in 11, leiomyosarcoma in 5, malignant neurogenic tumor in 5, and others in 9. Tumor cells in 31 of 70 cases (44%) showed positive nuclear staining for p53 protein. There was no correlation between p53 expression and tumor size, histologic grade, argyrophilic nucleolar organizer region (AgNOR) count, cellularity and extent of neerosis. Expression of p53 did not correlate with survival of patients. Tumor cells in 24 of 56 cases (43%) were positive for bcl-2 protein expression. The frequency of bcl-2 expression in the tumor cells showed a direct proportion to tumor size (> or = 10 vs. < 10 cm) but inverse proportion to AgNOR counts and cellularity. The 5-year survival rate in patients with bcl-2-positive tumors (87%) was more favorable than in those with bcl-2-negative tumors (53%; p < 0.05). The frequency of apoptosis in low-grade STS was significantly higher than that in the intermediate and high-grade STS (p < 0.001). Extent of necrosis, a well-known prognostic indicator in STS, was not correlated with the frequency of apoptosis. Multivariate analysis showed that cellularity, bcl-2 and AgNOR counts were independent prognostic factors in patients with STS. The current study revealed that STS with a higher expression of bcl-2 had lower proliferative activity and larger size than those without. Immunohistochemical detection of bcl-2 is useful for predicting prognosis in patients with STS.

Adolescent↗

Growth inhibition of human osteosarcoma HuO9 cells by methylglyoxal bis(cyclopentylamidinohydrazone) in vitro and in vivo.

Polyamines are considered to be important intracellular molecules for the proliferation of cancer cells. In this study, effects of methyl-glyoxal bis(cyclopentylamidinohydrazone) (MGBCP), a potent inhibitor of the polyamine biosynthetic pathway, on the growth of human osteosarcoma HuO9 cells have been investigated. MGBCP dose-dependently inhibited the growth of HuO9 cells, in which the contents of spermine, spermidine and putrescine decreased concomitantly. The MGBCP-treated cells clearly exhibited morphological changes, indicating the blebbing and chromatin condensation which are characteristic of apoptosis. Characteristic oligonucleosomal-sized DNA fragments were observed in the MGBCP-treated cells. In in vivo experiments MGBCP (20 or 50 mg/kg) inhibited the growth of transplanted HuO9 tumors in mice. These findings suggest that the inhibition of polyamine synthesis results in the suppression of growth of osteosarcoma HuO9 cells, eventually inducing apoptosis in these human osteosarcoma cells in vitro and in vivo.

Animals↗

Effects of biopsy on lung metastasis.

In order to clarify whether biopsy promotes lung metastasis, open or needle aspiration biopsy was performed 10 or 21 days after S-SLM osteosarcoma cells were transplanted subcutaneously in Fischer rats. The lungs were excised after six weeks and the lung weight and the number of metastatic nodules were measured. The mean weight was more in open than needle biopsy, and the number of nodules was significantly higher in open biopsy after 10 days, compared to the control. From these results we concluded that open is more likely to promote lung metastases compared to needle biopsy under the specific experimental conditions of this study.

Animals↗

Lack of spontaneous and inducible natural killer cell activity in human bone marrow: presence of adherent suppressor cells.

Human bone marrow cells collected from ribs of patients undergoing thoracotomy had low or no natural killer (NK) cell activity against K562 in a 4-hour chromium release assay. In vitro overnight treatment with interferon or interleukin 2 of bone marrow cells resulted in no induction or augmentation of NK cell activity. In the presence of adherent bone marrow cells interferon was unable to enhance NK cell activity of blood lymphocytes, although the baseline level of NK cell activity was not suppressed. These results suggest that adherent bone marrow cells regulate the development of active NK cells and that bone marrow components do not provide a favorable environment for the functional differentiation of NK cells.

Adult↗

Role of NK cell cytotoxic factor against fresh human tumors.

Blood lymphocytes of cancer patients lysed autologous, freshly isolated tumor cells. The autologous tumor-killing (ATK) activity is strongly associated with postoperative clinical course, indicating that ATK is a meaningful prognostic indicator and provides evidence for immunological control of tumor growth and metastasis. Large granular lymphocytes (LGL) with ATK activity released a soluble cytotoxic factor(s), termed LGL-CF (LGL-derived cytotoxic factor) during interaction with autologous tumor cells. The cytotoxic factor lysed autologous and allogeneic freshly isolated human tumor cells, while they were resistant to any of recombinant cytokines, including tumor necrosis factor (TNF), lymphotoxin (LT), interferon (IFN) alpha, IFN gamma, interleukin (IL)-1 alpha and IL-2. Biological activity of LGL-CF was not abrogated by monoclonal and polyclonal antibodies against these cytokines. LGL-CF also exhibited lysis of a variety of tumor cell lines, but not of nonmalignant cells. Actinomycin D augmented the lysis of LGL-CF. LGL-CF was stable at 56 degrees C, but was destroyed at 100 degrees C. Treatment of LGL-CF with trypsin or proteinase K reduced or abrogated the lytic effect, respectively, while it was resistant to papain, catalase, and superoxide dismutase. These results indicate that LGL produce a novel cytotoxic factor in response to autologous tumor cells that mediates lysis of fresh human tumor cells.

Cytokines↗

Effects of methylglyoxal bis (cyclopentylamidinohydrazone) (MGBCP) on cell cycle progression in three human osteosarcoma cell lines.

Our previous experiments have indicated that the antitumor effects of a polyamine biosynthetic inhibitor, methylglyoxal bis(cyclopentylamidinohydrazone) (MGBCP), on human osteosarcoma cell lines such as MG-63, G-292 and HOS cells are obtained by its action depleting the cellular polyamine contents. In the present study, the effects of polyamine depletion by MGBCP on the cell cycle progression in these osteosarcoma cell lines were investigated by flow cytofluormetric analysis. MGBCP arrested the tumor cells at the G1 phase by preventing the G/S phase transition. Mitotic indexes (MIs) in these MGBCP-inhibited tumor cells were also decreased. These findings suggest that MGBCP suppresses the cell cycle progression in osteosarcoma MG-63, G-292 and HOS cells by inhibiting intracellular polyamine biosynthesis.

Antineoplastic Agents↗

Induction of apoptotic cell death in three human osteosarcoma cell lines by a polyamine synthesis inhibitor, methylglyoxal bis(cyclopentylamidinohydrazone) (MGBCP).

Our previous experiments have shown that methylglyoxal bis(cyclopentylamidinohydrazone) (MGBCP), a polyamine synthesis inhibitor, suppresses the growth of osteosarcoma cells repressing their intracellular polyamine levels, and that this inhibition of cell growth is only partially reversed by the addition of polyamines. In the present study, we found evidence indicating that the incomplete recovery of cell growth by the addition of polyamines to the polyamine-depleted cells was due to programmed cell death (apoptosis) induced by MGBCP. Morphological changes showing blebbing and chromatin condensation were observed in MGBCP-treated cells, and hypodiploid subpopulations containing apoptotic cells were clearly visible in the profile of flow cytometric analysis. Characteristic oligonucleosomal-sized fragments were increased as the concentration of MGBCP was increased. The results presented here suggest that in addition to reducing the growth rates, MGBCP can induce apoptotic cell death in three human osteosarcoma cell lines.

Apoptosis↗