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Biomedical subjects

Y Tsuji

Publications and source records attributed to Y Tsuji.

At least 271 records · Page 15Linked to original sources
PubMed1994

Intraluminal content is required for the maintenance of antigrade proluminal movement of 3H-androgens into rat caput epididymal tubules.

The present study was undertaken to determine whether or not antigrade, proluminal 3H-androgen movement in the caput epididymis occurs in the absence of native lumen content. A single tubule was perfused with artificial caput fluid containing no androgen-binding protein for 30 min and subsequently tubules were perifused with Minimum Essential Medium perifusion fluid containing 26.7 microCi/ml 3H-testosterone and 1.3 microCi/ml 14C-polyethyleneglycol for 1 h. Radioactivity of isotopes in perifusion and intraluminal fluids was determined at 1 h after sustaining perifusion, and the percentage of peritubular isotopes appearing in the intraluminal fluid was determined. Net entry of 3H-androgen into the epididymal tubules in the presence of native intraluminal content was approximately 323%. In contrast, intraluminal 3H-androgen concentrations in the epididymal fluid in the absence of native lumen content were significantly reduced, to 100% of those in the peritubular fluid. Antigrade, proluminal movement of 3H-androgen in the caput epididymis does not occur in the absence of native lumen content. Androgen-binding protein in the epididymal lumen may be required to maintain uphill proluminal movement of 3H-androgen into the tubules.

Androgens↗
PubMed1994

Effects of protein synthesis inhibitor and antimicrotubular agent on transepithelial movement of 3H-androgens in the rat caput epididymis.

The effects of protein synthesis inhibition and disassembly of microtubules in the epididymal epithelia on proluminal movement of 3H-androgens were investigated by using in vivo microperifusion of 3H-testosterone and subsequent micropuncture to obtain peritubular and intraluminal fluids of caput epididymal tubules. Cycloheximide (100 micrograms/ml) was used as protein synthesis inhibitor. Nocodazole (3 micrograms/ml) was used to depolymerize microtubules in the cell. The perifusion fluid was Minimum Essential Medium containing 26.7 microCi/ml 3H-testosterone and 1.3 microCi/ml 14C-polyethyleneglycol (14C-PEG), or the same fluid supplemented with cycloheximide or nocodazole. Radioactivity of 3H-androgen and 14C-PEG in perifusion and intraluminal fluids was determined at one hour after initiation of the sustaining perifusion, and the percentage of radioactivity of 3H-androgen and 14C-PEG appearing in the intraluminal fluid to that in the peritubular fluid was determined. Proluminal movement of 3H-androgens into the caput epididymal tubules in the control rats was 323.4 +/- 73.2%. This value was significantly reduced to 121.8 +/- 13% by addition of cycloheximide to the perifusion fluid (p < 0.01). Transepithelial movement of 3H-androgen in the caput epididymis was significantly decreased to 86.6 +/- 5.3% by exposure of the epididymal tubules to nocodazole (p < 0.01). Inhibition of protein synthesis and disassembly of microtubules in the epididymal epithelial cells completely eliminated antigrade proluminal movement of 3H-androgen into the tubules. Study of the incorporation of 35S-Methionine into epididymal tissue protein revealed significant reduction of the quantity of radiolabeled proteins in the perifused tissue with fluid containing cycloheximide (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

The effect of varicocele ligation on oocyte fertilization and pregnancy after failure of fertilization in in vitro fertilization-embryo transfer.

Although varicocelectomy is generally believed to improve semen quality and the hamster egg penetration assay, these parameters do not correlate well with in vitro fertilization (IVF) success. The effect of varicocelectomy on IVF of human oocytes was examined on thirteen couples with normal female fertility, but severe oligozoospermia and the presence varicocele in the males with failure of fertilization preoperatively in in vitro fertilization-embryo of transfer (IVF-ET) attempts. The couples were readmitted for the IVF-ET procedure following varicocelectomy. A 31% pregnancy rate was achieved after the operation, while no pregnancies occurred before surgery. Sperm density and motility improved significantly after operation, resulting in a coinciding improved fertilization and pregnancy rates.

Embryo Transfer↗
PubMed1994

[A case of liver metastasis from bile duct cancer effectively treated with hepatic artery infusion chemotherapy].

We performed hepatic artery infusion chemotherapy (HAI) combined with 5-FU-MMC-EPIR for bile duct cancer metastasized to the liver. We report a case for which we obtained PR. The case was a 59-year-old woman, who was diagnosed to have multiple liver metastases with an increase of CEA and LDH after 6 months from absolute curative resection for middle bile duct cancer. The patient was catheterized into the proper hepatic artery through the right femoral artery, and 5-FU 500 mg qw, MMC 4 mg q2w, and EPIR 30 mg q4w were infused via a reservoir. Two months after the treatment was begun, CEA and LDH values became normal. At the same time, PR was obtained and was shown upon CT, which continued for 5 months. After an 8-month period during which the patient was an outpatient at PS-0, multiple bone metastases appeared, and the radiotherapy was combinedly utilized for each lesion. The side effect of this method was decrease of leukocytes and blood platelets, but it disappeared by discontinuing medication. The patient died two years after the first operation, a year and four months from the time HAI was begun. It was possible to continue this treatment with PS 1-2 on an outpatient basis until one month before the patient's death. We concluded that hepatic artery infusion chemotherapy is an effective therapeutic method.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

The indirect participation of growth hormone in the thymocyte proliferation system.

The specific binding sites for growth hormone was recognized on both thymic lymphocytes (thymocytes) and thymus epithelial cells. The somatotropic action of GH is considered to be mediated mainly by insulin-like growth factor-1 (IGF-1) and partially by GH itself. In this study, effect of GH and IGF-1 on DNA synthetic activity of thymocytes was examined. By 48-hrs. culture with IGF-1 and 24-hrs. 3H-TdR pulse labeling, significant enhancement of DNA synthetic activity of thymocytes was detected, while the enhancement in the culture with GH was very weak. It is considered that IGF-1 acts on the cells in G0/G1 phase in cell cycle. The effect of IGF-1 on thymocyte proliferation was examined by using the thymocytes incubated 12 hrs. before IGF-1 stimulation and 3-hrs. 3H-TdR pulse labeling. The optimal condition to induce thymocyte proliferation was 15-hrs. culture with 380 ng/ml of IGF-1. Furthermore, 10 ng/ml or higher concentration of GH significantly increases IGF-1 release from TECs in confluent state. These results suggest that GH indirectly participates in thymus growth by increasing IGF-1 release from TECs, which enhances thymocyte proliferation.

Animals↗
PubMed1994

[Complete response in a case of unresectable gastric cancer treated by combined chemoimmunotherapy of MMC, 5-FU and OK-432].

A 68-year-old female patient with unresectable advanced gastric cancer was treated by combined administration of MMC (10 mg/month), 5-FU (200 mg/day) and OK-432 (5KE/2 weeks). Two months after starting the treatment, there was a diminution in the serum CEA level. Six months later, the CEA had decreased to the normal level, primary and metastatic sites completely disappeared and no cancer cell was confirmed by endoscopic biopsy. The patient has survived for 33 months of a state of complete response.

Adenocarcinoma↗
PubMed1994

[Studies on cell-mediated immunity (CMI) in the glomeruli: immunization with GBM antigen from Masugi nephritis in Wistar-Kyoto rats].

The role of cell-mediated immunity in glomerular injury has been extensively studied, but the precise mechanism remains obscure. This study was undertaken to determine whether the homologous glomerular basement membrane (GBM) combined heterogeneous anti-GBM antibody would induce cell-mediated immunity. Wistar-Kyoto rats were divided into three groups; group I rats were immunized with homologous GBM antigen that was derived from Masugi nephritis and emulsified in complete Freund's adjuvant (CFA); group II rats were immunized with homologous GBM antigen that was derived from normal rats and emulsified in CFA; group III rats were immunized with CFA only. Group I rats demonstrated proteinuria on days 7 and 10 after immunization. Histologically, mesangial cell proliferation and cell infiltration were observed in the glomeruli. No changes in tubulointerstitial tissue. CD4-positive cells, CD8-positive cells and macrophages were found in the glomeruli, and mononuclear cells were found in the glomerular capillary lumen. Group II and Group III rats demonstrated no proteinuria and no histological changes. These findings indicated that the altered GBM obtained antigenicity and induced cell-mediated immunity in the glomeruli.

Animals↗
PubMed1994

Intervention of maternal transmission of HTLV-1 in Nagasaki, Japan.

Seroepidemiological and laboratory virological evidences strongly suggested that endemicity of HTLV-1 in Nagasaki Japan depends on maternal infant infections via breast milk. The most obvious way to prove this concept was an intervention study with refraining from breast-feeding by carrier mothers. Most infected babies seroconverted by the age of 12 months, which made it possible to diagnose the infection at the age of 12 months for the statistical purpose. Serology and PCR on both adults and children were consistent each other, suggesting the absence of seronegative carriers. The intervention study revealed that approximately 80% of maternal infection was prevented by refraining from breast feeding by carrier mothers. The remaining fraction of infections in formula-fed babies suggested an alternative infection pathway. Although intrauterine infections has been suggested by others to explain the PCR-positive cord blood samples. However, groups of cord blood-positive children and seroconverted children were distinct each other. Therefore, the presence of HTLV-1 provirus in the cord blood can not be a marker of intrauterine infection. Mothers who infected a child has approximately 10 times higher risk of another infection for the next baby than those who did not.

Breast Feeding↗
PubMed1993

Preferential repression of the H subunit of ferritin by adenovirus E1A in NIH-3T3 mouse fibroblasts.

Ferritin is the major intracellular iron-storage protein in eucaryotic cells and plays a prominent role in maintaining intracellular iron homeostasis. We observed that transfection of NIH-3T3 mouse fibroblasts with the adenovirus E1A oncogene specifically repressed the mRNA for one of the subunits of ferritin, ferritin H. This occurred in the absence of any effect of E1A on the mRNA for the L subunit of ferritin. The repression of ferritin H was not a general feature of oncogene expression since transfection of NIH-3T3 cells with H-ras did not affect ferritin composition. Deletion of the conserved regions of E1A responsible for immortalization and transcriptional repression impaired the ability of E1A to repress ferritin H. Immunoprecipitation of ferritin in E1A transfectants demonstrated that the decrease in the ferritin H/L ratio observed at the mRNA level was also exhibited at the protein level. The E1A-dependent inhibition of ferritin H was also observed in a chimeric gene containing the ferritin H promoter ligated to the chloramphenicol acetyltransferase reporter gene, but was not observed in control genes in which chloramphenicol acetyltransferase activity was dependent on promoters derived from SV40 or the interleukin-3 gene. This suggests that E1A may repress ferritin H at the transcriptional level. These results demonstrate that the adenovirus E1A oncogene specifically modulates ferritin H expression. They also suggest that alterations in cellular iron metabolism may be among the diverse array of cellular responses induced by E1A.

3T3 Cells↗
PubMed1993

Augmentation by IL-1 alpha of tumor necrosis factor-alpha cytotoxicity in cells transfected with adenovirus E1A.

The introduction of adenovirus E1A into NIH3T3 mouse fibroblasts renders them susceptible to the cytotoxic action of TNF-alpha. We found that cells transfected with 13S E1A cDNA were not similarly rendered sensitive to IL-1 alpha; however, in cells transfected with 13S E1A cDNA, TNF cytotoxicity was augmented by treatment with IL-1. To understand the role of E1A in the cytotoxic action of these cytokines, several 13S E1A cDNA deletion mutants were constructed, transfected into NIH3T3 cells, and tested for their ability to induce TNF sensitivity in the presence and absence of IL-1. Cells transfected with mutants of 13S E1A with deletions of carboxyl-terminal amino acids 223 to 289 or 151 to 289 (conserved region 3) exhibited a minimal ability to reverse E1A-induced TNF cytotoxicity but a significant ability to reverse IL-1-mediated augmentation of TNF cytotoxicity. Cells transfected with other deletion mutants of 13S E1A, including those with an internal deletion encompassing conserved region 1 (amino acid positions 23 to 107) or a deletion including conserved regions 2 and 3 (amino acid positions 108 to 289), although initially TNF resistant, became TNF sensitive on prolonged exposure to TNF. Cells transfected with these mutants also showed a reduction in IL-1-augmented TNF cytotoxicity. The larger internal deletion of E1A at amino acid positions 23 to 150 (conserved regions 1 and 2), which includes regions important for transformation, transcriptional repression, and association with cellular proteins, resulted in the complete loss of the ability of E1A to induce TNF sensitivity even in the presence of IL-1. Immunoprecipitation experiments showed that E1A proteins in NIH3T3 cells associated with a cellular 115-kDa protein, which did not co-migrate with the RB gene product; the possible involvement of this protein in E1A-mediated TNF cytotoxicity is discussed. Taken together, these results indicate that conserved regions 1 and 2 are required for E1A-mediated TNF cytotoxicity. In contrast, maximal IL-1-augmented TNF cytotoxicity requires conserved region 3 as well as the nonconserved carboxyl-terminal region of the 13S E1A product.

3T3 Cells↗
PubMed1993

Transglycosylation activity of endoglycoceramidase from Corynebacterium sp.

Endoglycoceramidase (EGCase) catalyzes the hydrolysis of the linkage between oligosaccharides and ceramides of various glycosphingolipids (GSLs). We found that the EGCase from Corynebacterium sp. had transglycosylation activity. Digesting GSLs with the enzyme in the presence of a suitable acceptor gave a mixture of hydrolytic and transglycosylic products. When GM1 was used as the substrate (donor), 1-hexanol was found to be the best acceptor of transglycosylation activity. Hexyl-II 3NeuAcGgOse4 produced was confirmed by fast-atom bombardment-mass spectrometry analysis and exoglycosidase digestion. The enzyme also transferred oligosaccharides of various GSLs to 1-hexanol.

Corynebacterium↗
PubMed1993

Selective loss of CDC2 and CDK2 induction by tumor necrosis factor-alpha in senescent human diploid fibroblasts.

Normal human diploid fibroblasts undergo a finite number of doublings in culture. This process of senescence is accompanied by a loss in the ability to respond to proliferative stimuli and is therefore distinct from the quiescent state induced by nutrient deprivation. We have studied changes in gene expression induced in these cells following exposure to the cytokine, tumor necrosis factor-alpha (TNF). We observed that TNF induced CDC2 and CDK2 expression in early-passage quiescent WI-38 fibroblasts. However, as cells approached senescence, their ability to induce CDC2 and CDK2, as well as stimulate DNA synthesis in response to TNF, progressively declined, with minimal to absent induction in senescent cells. This occurred despite the TNF-dependent induction of such proliferation-independent genes as manganese superoxide dismutase and interleukin-6 in senescent and quiescent cells. Serum was similarly unable to induce CDC2 or CDK2 expression in senescent cells. These results demonstrate that senescent cells are selectively deficient in TNF-mediated induction of CDC2 and CDK2, genes crucial to DNA synthesis and mitosis.

CDC2 Protein Kinase↗
PubMed1993

An experimental model for unilateral ischaemic acute renal failure in dog.

We determined the recovery of unilateral ischaemic acute renal failure in both ischaemic and non-ischaemic canine kidneys. Split renal clearance studies were repeated for seven weeks after 90 minutes of left renal artery clamping. Clearance of inulin and para-aminohippuric acid in the ischaemic kidneys dropped significantly for 3 weeks. Significant increase of the fractional excretion of sodium in those kidneys was observed at only 1 week after ischaemia. In the contralateral non-ischaemic kidneys, these indices did not change significantly throughout the experiments. This animal model of acute renal failure would be helpful in testing possible preventive measures and therapy for human acute renal failure.

Acute Kidney Injury↗
PubMed1993

Determination of immunoglobulin classes and subclasses of sperm immobilizing antibodies in infertile women and the inhibitory effect of IgG4 subclass on the sperm immobilizing antibody activity.

Immunoglobulin classes and subclasses of sperm immobilizing antibodies (SI-Abs) in the sera of sterile women were determined by the absorption of patients' sera with Staphylococcus aureus and immunoadsorbents bound with class or subclass-specific anti-human immunoglobulin antibodies. Among 18 patients' sera tested, 16 had the IgG-dominant SI-Abs and the remaining 2 sera contained IgM-dominant SI-Abs. From the former patients' sera, 9 were further studied to determine the IgG subclasses; 6 of them had IgG1-dominant SI-Abs, one IgG2-dominant, and in the other two IgG1 and IgG2 were equally dominant. Interestingly, SI-Ab activities in 6 of the 9 patients' sera increased after absorption of IgG4 subclass and the addition of IgG4 purified from an SI-positive patient to the same patient's serum diminished the SI-Ab activities.

Complement Activation↗
PubMed1993

Enhanced antitumor effect of recombinant human tumor necrosis factor in combination with recombinant human granulocyte colony-stimulating factor in BALB/c mice.

The synergistic antitumor effect of tumor necrosis factor (TNF) and granulocyte colony-stimulating factor (G-CSF) was investigated. G-CSF was administered subcutaneously to BALB/c mice inoculated with Meth-A cells at a dose of 2.5 micrograms/day for 5 consecutive days. When TNF (1 x 10(3) U) was administered intravenously to mice which had been pretreated with G-CSF, tumor growth showed a 74.1% inhibition 17 days after the tumor cell inoculation, compared to that of untreated mice. In this experiment, G-CSF significantly (P < 0.025) enhanced the antitumor effect of TNF. The in vitro cytotoxicity of TNF (10 U/ml) towards Meth-A cells was increased about 5.2-fold in the presence of neutrophils (E/T = 50) as compared to the cytotoxicity obtained with TNF alone. A combination of TNF and G-CSF (50 ng/ml) in the presence of neutrophils, resulted in a 2.1 times greater cytotoxicity against Meth-A cells as compared to that obtained without G-CSF. Significant augmenting effects of G-CSF on superoxide (O2-) production by TNF-stimulated neutrophils were observed. These observation suggest that the neutrophil plays an important role in the antitumor action of TNF on Meth-A cells, and that the antitumor effect of TNF is enhanced by combination with G-CSF.

Animals↗
PubMed1993

A cancer-reactive human monoclonal antibody derived from a colonic cancer patient treated with local immunotherapy.

A human monoclonal antibody, YJ-37 (IgM) was generated through the fusion of human B lymphoblastoid cell line HO-323 with the regional lymph node lymphocytes from a colonic cancer patient who was treated with a local immunotherapy. This antibody was purified and conjugated with biotin, after which direct immunohistochemical staining was performed. The results revealed that YJ-37 selectively reacted with colonic cancer (7/19), gastric cancer (3/6), endometrial cancer (1/2) and colonic adenoma (7/13), but not with normal epithelia. Membrane immunofluorescence and FACS analysis also showed that YJ-37 bound to tumor cell surfaces. Furthermore, the chemical structure of the antigen defined by YJ-37 was analyzed by means of thin-layer chromatography immunostaining and ELISA. The results indicated that YJ-37 reacted with sialylated lacto-series carbohydrate chains, which have been reported to accumulate in cancer cells.

Adenoma↗