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Biomedical subjects

Y Tsuji

Publications and source records attributed to Y Tsuji.

At least 307 records · Page 17Linked to original sources
PubMed1993

[Intra-arterial chemotherapy with 5-FU (weekly high dose 5-FU HAI) for the prevention of tumor recurrence in residual liver after hepatic resection of metastasis from colorectal cancer].

Intra-arterial cancer chemotherapy using an implantable reservoir was performed for the prevention of tumor recurrence in residual liver after resection of a metastatic tumor from colorectal cancer. Four cases of synchronous hepatic metastases and one case of metachronous hepatic metastasis, which were in H1 (2 cases) and H2 (3 cases), were treated. 5-FU was administered in a dose of 1,000 mg/m2 5 hours weekly (weekly high dose 5-FU HAI). The longest survival obtained is 1Y 11M. Other cases have survived for 1Y 7M, 1Y 12M, 9M, and 3M. Tumor recurrence was not observed in all cases except one. This case had a residual tumor because the complete resection was impossible. The tumor recurrence rate in patients treated with surgery alone at Nikko Memorial Hospital (n = 11) was 63.6%. The 1- and 2-year survival rate in these patients was 60.6% and 26.9%, respectively. As compared to these rates, the results of this study were very favorable. Although mild nausea and abdominal discomfort were observed in 1 patient, this adverse effect was reduced by administration of an anti-ulcer agent. Only a slight decrease of WBC and PLT counts was observed. Consequently, for residual liver after resection of hepatic metastasis from colorectal cancer, this intraarterial chemotherapy with 5-FU is considered to be effective to prevent tumor recurrence and thus to prolong survival.

Aged↗
PubMed1993

[Oxygen radicals].

Oxygen radicals such as O2- and H2O2 induce bronchoconstriction and airway hyperresponsiveness in animal models. Eosinophil peroxidase (EPO)+H2O2+halide system cause damage of respiratory epithelium, in vitro. Damage to airway epithelium may decrease the release of epithelium-derived relaxing factor (EpDRF) and trigger an axon reflex with the release of neuropeptides, such as substance P. Activated human eosinophils can release various inflammatory mediators, such as oxygen radicals, eosinophil granule proteins and leukotrienes, in vitro. The degree of the damage of the bronchial epithelium and the number of infiltrated and activated eosinophils in the bronchial epithelium correlate with the level of airway responsiveness in bronchial asthma patients. Therefore, eosinophil-derived oxygen radicals may contribute to the epitherial damage and enhance airway hyper-responsiveness in bronchial asthma.

Animals↗
PubMed1993

[A case of papillary renal cell carcinoma presenting as a large cyst with massive hemorrhage].

A case of unusual renal cell carcinoma in a 25-year-old male is reported. The patient complained of right flank pain and a mass in the right upper quadrant of the abdomen. Selective renal arteriography revealed a hypovascular tumor at the lower pole of the right kidney. Right partial nephrectomy was performed. The mass, having a large cystic appearance with hemorrhage, was pathologically confirmed to be papillary renal cell carcinoma. We briefly discussed the specific features of papillary renal cell carcinoma in young adults and cystic changes in renal cell carcinoma.

Adult↗
PubMed1992

Endogenous tumor necrosis factor functions as a resistant factor against hyperthermic cytotoxicity.

One of the mechanisms of cytotoxicity by tumor necrosis factor (TNF) is the induction of reactive oxygen molecules. Cells producing endogenous tumor necrosis factor (enTNF) show resistance to the cytotoxicity of exogenous TNF by scavenging the reactive oxygen molecules. The intracellular hydroxyl radical production is also known to be involved in the heat-induced cytotoxicity. In the present study, we therefore examined the possibility that enTNF may act as a protective protein against the heat-induced cytotoxicity in a manner similar to that of exogenous TNF. Heat-sensitive L-M (mouse tumorigenic fibroblast) cells, originally expressing no enTNF, were transfected with a human TNF expression vector to produce enTNF. The stable transfectants showed apparent resistance to heat treatment. Conversely, when HeLa (human uterine cervical cancer) cells, originally producing an appreciable amount of enTNF, were transfected with an antisense TNF mRNA expression vector to inhibit enTNF synthesis, their heat sensitivity was enhanced. Furthermore, L-M cells which were transfected with nonsecretory human TNF expression vector also acquired resistance to heat treatment. In these cells, heat resistance correlated well with expression of enTNF and intracellular levels of manganous superoxide dismutase. These results indicate that enTNF exerts its intracellular protective effect against the heat-induced cytotoxicity by scavenging reactive oxygen with induced manganous superoxide dismutase in a manner similar to that found in cells treated with exogenous TNF.

Animals↗
PubMed1992

Endogenous tumor necrosis factor exerts its protective function intracellularly against the cytotoxicity of exogenous tumor necrosis factor.

Based on the findings that expression of endogenous tumor necrosis factor (enTNF), which is not present in TNF-susceptible cells, was generally observed in TNF-resistant cells and that TNF gene transfection gives rise to TNF resistance, the assumption was made that enTNF may be a protective protein against the cytotoxicity of exogenous TNF. However, it remains unknown whether the protection by enTNF is exerted in an intracellular or extracellular (autocrine) manner. We therefore transfected a nonsecretory human TNF gene (pTNF delta pro) into highly TNF-sensitive mouse tumorigenic fibroblasts (L-M cells) and investigated their TNF susceptibility. The transfectants expressed enTNF which was not secreted into the medium and acquired an appreciable degree of resistance to exogenous TNF. A significant increase in the manganous superoxide dismutase level was also noted in the transfectants. These findings suggest that enTNF exerts its protective function intracellularly by inducing manganous superoxide dismutase production.

Animals↗
PubMed1992

Purification and some properties of L-fucose dehydrogenase from Agrobacterium radiobacter and its application to the assay of bound-fucose in glycoconjugates.

L-Fucose dehydrogenase was found in the cell extract of Agrobacterium radiobacter and purified to homogeneity about 480-fold with 16% recovery. The molecular weight of the enzyme was approx. 64,000. The enzyme was active in the neutral pH range, unlike other L-fucose or D-arabinose dehydrogenases which are active only in the alkaline pH range. Using this enzyme and alpha-L-fucosidase F-I of Bacillus circulans (Tsuji, Y., Yamamoto, K., Tochikura, T., Seno, T., Ohkubo, Y. and Yamaguchi, H. (1990) J. Biochem. 107, 324-330) simultaneously, we developed a new coupled enzymatic method in a single buffer system for determining bound-fucose in biological materials. The fucose released by alpha-L-fucosidase F-I was oxidized with L-fucose dehydrogenase in the presence of NAD+, and the NADH formed was measured by absorbance of ultraviolet or utilized to generate color in a reaction involving CuSO4 and neocuproine. Using these methods, bound-fucose in various oligosaccharides and proteins such as lacto-N-fucopentaoses and porcine gastric mucin were quantitated within 15 min.

Animals↗
PubMed1992

Induction of synthesis of manganous superoxide dismutase in L-M(pNTnF) cells carrying an inducible TNF gene.

Based on findings that the cytotoxic effects of tumor necrosis factor (TNF) are closely related to levels of intracellular oxygen radicals, and on the results of TNF gene transfection studies, the hypothesis was made that endogenous TNF (enTNF) acts as a protective factor against exogenous TNF by inducing inhibitors or scavengers of oxygen radicals. In order to test this hypothesis, we investigated the intracellular levels of manganous superoxide dismutase (MnSOD) and glutathione (GSH) in L-M(pNTnF) cells carrying a TNF gene induced by dexamethasone (DM). When L-M(pNTnF) cells were treated with DM they expressed enTNF, and acquired resistance to exogenous TNF. There was no change in the GSH concentration after enTNF induction, but a 1.9- to 3.9-fold increase in MnSOD levels was noted. Our findings suggest that enTNF exerts its protective function against the cytocidal effect of exogenous TNF by inducing MnSOD production.

Animals↗
PubMed1992

Sperm immobilizing antibodies react to the 3-O-sulfated galactose residue of seminolipid on human sperm.

It is well known that very few women who possess sperm immobilizing antibodies in their sera can conceive naturally even though there are no abnormalities in their reproductive organs on routine medical examination. A monoclonal antibody (MAb), designated 2H12, was produced by immunizing a BALB/c mouse with the human choriocarcinoma cell line JEG-3. MAb 2H12 showed strong sperm immobilizing activities and reacted to sulfatide and seminolipids. The sperm immobilizing activities of 2H12 were clearly absorbed with sulfatide or seminolipid whilst several other sperm immobilizing MAbs that were made by immunization with human sperm or seminal plasma could not be absorbed with the same sulfoglycolipids. The sperm immobilizing antibodies in the sera of infertile women with unknown cause were also clearly absorbed with sulfatide or seminolipid. MAb 2H12-conjugated immunobeads (MAb 2H12-IMBs) bound to motile sperm. This binding of 2H12-IMBs to sperm was competitively inhibited either by 2H12 or women's sera containing sperm immobilizing antibodies, but not by normal women's sera or several other sperm immobilizing MAbs to human sperm. These results suggest that the sperm immobilizing antibody in women's sera is directed against the 3-O-sulfogalactose residue of seminolipid on the sperm membrane.

Animals↗
PubMed1992

In vivo measurement of spatial dose distribution with thermoluminescent sheet around high dose-rate intracavitary source: application to rectal cancer.

For intracavitary high dose-rate radiation therapy, a thermoluminescent [TL] sheet for in vivo measurement of spatial dose distribution around source has been recently developed. The TL sheet was found to have a linear response with a very wide dynamic range from at least 0.002 cGy to 5000 cGy for 60Co gamma-rays. This TL sheet (40 cm x 50 cm x 200 microns), which is composed of Teflon mixed with BaSO4:Eu doped powder, is very flexible and can be cut to the desired size. In addition, this sheet is easy to handle because of its insensitivity to room light. The spatial dose distribution is displayed in a color mode by using a newly developed TL sheet readout system. For a clinical application, the TL sheet was wrapped on an applicator for intracavitary radiation therapy of a rectal cancer and was inserted into the rectum. The location of the TL sheet could be confirmed with diagnostic X ray film. After irradiation with high dose-rate 60Co source, the in vivo relative dose distribution on the surface of the rectum was determined. This TL sheet provided a convenient means of measuring the relative dose distributions around 60Co sources of various patterns in intracavitary radiation therapy.

Brachytherapy↗
PubMed1992

Serum calcium increases the incidence of arrhythmias during acetate hemodialysis.

We investigated the occurrence of arrhythmias during maintenance acetate hemodialysis (HD) using a 24-hour continuous electrocardiogram recording system. Three of 22 patients showed augmented increases in both ventricular premature beats and supraventricular premature beats during HD. When we changed the dialysate from one with a Ca2+ concentration of 1.75 mmol/L (3.5 mEq/L), to one with a Ca2+ concentration of 1.25 mmol/L (2.5 mEq/L), the elevation of serum Ca2+ concentration during HD was abolished and the increases in both ventricular premature beats and supraventricular premature beats were significantly decreased. The elevation of serum Ca2+ concentration during HD might induce either extracellular or intracellular increase in Ca2+ concentration in the heart and elicit either reentry- or triggered-activity types of arrhythmias during HD. The present results indicate that the dialysate with a lower Ca2+ concentration is advisable to use in patients with underlying cardiac diseases.

Acetates↗
PubMed1992

Ultrastructural analysis of pseudo-intimal hyperplasia of polytetrafluoroethylene prostheses implanted into the venous and arterial systems.

To evaluate and compare the pathogenesis of pseudo-intimal hyperplasia (PH) of venous and arterial prostheses, a segment of the inferior vena cava (n = 16) or abdominal aorta (n = 16) was substituted by a 3 mm internal diameter polytetrafluoroethylene tube graft (PTFE, 3 cm long, 30 microns in nodal distance) in albino rabbits. At designated time intervals (3-28 days) after the replacement, graft patency was examined and the dry weights of the intraluminal deposits measured as an indicator of the degree of PH. The harvested grafts were then subjected to an ultrastructural analysis by means of light microscopy (LM), and scanning electron and transmission electron microscopy (SEM, TEM). All the grafts remained patent during the entire observation period. The PH judged by the dry weight was significantly more extensive in the venous than in the arterial prostheses. The PH on day 28, observed by light microscopes was apparently most extensive in the mid-portion of venous prostheses but in the arteria prostheses it was mostly seen at the anastomotic sites. The lining of the intraluminal surface of the prostheses with endothelial-like cells observed by SEM was faster and more extensive in venous than in arterial prostheses. The process of PH in venous prostheses observed by TEM may be divided into the following steps: early thrombosis, phagocytosis of the thrombus, appearance of fibroblasts, growth of endothelial-like cells, appearance of smooth muscle cells, and pseudointimal thickening and proliferation of fibroblasts producing collagen fibrils. The process in arterial prostheses was essentially identical to that in venous prostheses but was much slower and less extensive. From these observations, it was concluded that the formation of PH occurs much faster in venous than in arterial prostheses, although the mechanism of PH is mostly identical in venous and arterial prostheses.

Animals↗
PubMed1992

Clinical experience of laser angioplasty with angioscopic guidance.

Since 1986, intraoperative angioscopic observations have been followed by the study of laser angioplasty experimentally and clinically. The healing process of the lased arterial wall initially was evaluated angioscopically in the canine model. The lased area was observed as a crater covered with char soon after laser irradiation. One week after laser irradiation, subintimal bleeding around the crater and a small fresh thrombus on the crater were seen in some cases. Four weeks after laser irradiation, the crater was covered with new endothelium. In this experimental study angioscopy provides information which cannot be obtained by other means.

Aged↗
PubMed1992

A human monoclonal antibody derived from axillary lymph nodes of a breast cancer patient reactive to a sulfated glycolipid.

A human monoclonal antibody, BMMK-33G, was established by a fusion of human B-lymphoblastoid cells, HO-323, with lymphocytes of axillary lymph nodes obtained from a breast cancer patient. High-performance thin-layer chromatography (HPTLC)-immunostaining and enzyme-linked immunosorbent assay (ELISA) revealed that BMMK-33G was interestingly directed to enough sulfatide (Galactosylceramid-I2-sulfate), which is one of the sulfate ester containing glycolipids. By immunohistochemical staining, BMMK-33G intensely reacted to breast cancer, pancreatic cancer and gastric cancer. It also reacted to many normal human tissues including mammary glands, but these stainings were weaker than those for cancer. This report describes BMMK-33G, a human monoclonal antibody against sulfatide which may be very useful for studying not only tumor immunology but also autoimmune diseases.

Antibodies, Monoclonal↗
PubMed1992

Comparative studies of the antigens recognized by sperm-immobilizing monoclonal antibodies.

Characteristic properties of the antigens recognized by sperm-immobilizing monoclonal antibodies (SI-mAbs) from different sources were compared by ELISA competitive inhibition assay, Western blot analysis, chromatographic analysis, and enzymatic digestion studies. Among 9 SI-mAbs, human mAb H6-3C4 and three mouse mAbs--2C6, 2B6, and 2E5--also possessed strong sperm-agglutinating activity. Binding of human mAb H6-3C4 to sperm was strongly inhibited by the three mouse mAbs (2C6, 2B6, and 2E5), but not by the rat or the other four mouse mAbs. SDS-PAGE revealed that mAb H6-3C4 and three mouse mAbs recognized the same antigen molecules of 15-25 kDa present in both sperm extracts and seminal plasma. Chemical treatments with trifluoromethanesulfonic acid and sodium metaperiodate destroyed the antigen determinants recognized by the above four mAbs, as detected by both ELISA and antibody absorption tests. Western blot analysis revealed that the antigens were susceptible to treatments with papain, proteinase K, and N-glycanase, but resistant to trypsin, V8 protease, and thermolysin. These results indicate that one of the major antigens recognized by mAbs with sperm-immobilizing action may be a sperm membrane-associated glycoprotein of 15-25 kDa and the epitope may involve N-linked oligosaccharides.

Amidohydrolases↗
PubMed1992

Enhancement of lysosomal enzyme activity by recombinant human tumor necrosis factor and its role in tumor cell killing in vitro.

We investigated the effect of recombinant human tumor necrosis factor (TNF) on the lysosomal enzyme activity of various established cell lines in vitro. Incubation of 1 x 10(6) TNF-sensitive mouse tumorigenic fibroblasts (L-M cells) in the presence of TNF (100 U/ml) for 48 h increased the total (the sum of the enzyme activities in the lysosomes and the cytoplasm) acid phosphatase and beta-glucuronidase activities by 3.7- and 4.2-fold, respectively. The same increase was observed even when 1 U/ml of TNF was added to some cultures and no further augmentation occurred at 10 or 100 U/ml. Measurement of total and free enzyme activities showed that TNF stimulation not only enhanced the total intracellular enzyme activity but also accelerated the conversion into free (cytoplasmic) enzyme activity. Addition of a lysosomotropic agent (methylamine) suppressed both the enhancement of lysosomal enzyme activity and the cytotoxicity of TNF. A similar enhancement of lysosomal enzyme activities was also detected in various TNF-sensitive tumor cell lines, and a strong correlation (acid phosphatase: r = 0.836, beta-glucuronidase: r = 0.910) was observed between the enhancement of enzyme activity and sensitivity to TNF. No such increase was detected in TNF-resistant human diploid cells. These results show that TNF induces the activation and release of lysosomal enzymes in TNF-sensitive cells, and suggest that such events may play an important role in TNF-mediated cytotoxicity.

Acid Phosphatase↗
PubMed1992

Mechanism of synergistic cytotoxic effect between tumor necrosis factor and hyperthermia.

We previously reported that recombinant human tumor necrosis factor (rhTNF) and hyperthermia had a synergistic effect against tumors, in vitro and in vivo. We have now investigated the mechanism of this synergy by measuring the lysosomal enzyme activity and hydroxyl radical production of L-M cells treated with rhTNF and/or hyperthermia. A synergistic activation of lysosomal enzyme and the induction of hydroxyl radical production in L-M cells treated with both rhTNF and hyperthermia was observed. A synergistic cytotoxic effect was observed when rhTNF and hyperthermia were combined, and was inhibited by the addition of a reactive oxygen scavenger, dimethyl sulfoxide or bipyridine. The results show that the augmenting effect of hyperthermia on lysosomal enzyme activation and induction of hydroxyl radical production by rhTNF plays an important role in the synergistic cytotoxic effect.

Acid Phosphatase↗