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T Oda

Publications and source records attributed to T Oda.

At least 577 records · Page 32Linked to original sources
PubMed1987

Immunocytochemical localization of serine: pyruvate aminotransferase in peroxisomes of the human liver parenchymal cells.

The localization of serine:pyruvate aminotransferase (SPT) in human liver was investigated by indirect immunoenzyme and protein A-gold techniques. By light microscopy, diaminobenzidine reaction product was present in cytoplasmic granules of the parenchymal cells. By electron microscopy, gold particles indicating the antigenic sites for SPT were exclusively confined to peroxisomes but not to mitochondria. By double labeling technique, both peroxisomal marker enzyme, catalase and SPT were detected in the same peroxisomes. Quantitative analysis of the labeling density showed that SPT is contained only in peroxisomes. The results indicate that in human liver most of SPT is contained in the peroxisomes.

Humans↗
PubMed1987

Increased adenylate energy charges in rat liver or primary cultured rat hepatocytes by diisopropyl 1,3-dithiol-2-ylidenemalonate.

Six hours after oral administration in rat liver, diisopropyl 1,3-dithiol-2-ylidenemalonate (malotilate) decreased AMP concentrations by 60% with unchanged total adenine nucleotide concentrations and significantly increased adenylate energy charges of 0.87 in comparison to those of 0.81 in vehicle administered control animals. Twelve hours after incubation in primary cultured rat hepatocytes, malotilate decreased AMP concentrations by 18% and increased ATP and GTP concentrations by 13 and 18% respectively with significantly increased adenylate energy charges of 0.89 in comparison to 0.87 in vehicle control. Increased adenylate energy charges by malotilate coincided with the initiation of increases in protein and de novo purine synthesis in vivo, and are associated with the increased rate of de novo purine synthesis in vitro.

Adenine Nucleotides↗
PubMed1987

Effects of ATP and other nucleotides on DNA repair synthesis in bleomycin-pretreated permeable mouse sarcoma cells.

Effects of ATP and some other nucleotides (AMP, ADP, CTP, GTP, UTP and dATP) on reparative DNA synthesis and repair patch ligation in bleomycin-pretreated permeable mouse sarcoma cells were studied. Reparative DNA synthesis was significantly stimulated by 2.5 mM ATP, ADP or dATP. The stimulation was observed on both DNA polymerase alpha- and beta-dependent reparative DNA synthesis. ATP concentration required for repair patch ligation was much lower than that required for the stimulation of reparative DNA synthesis. An apparent Km value for ATP of the repair patch ligation was about 40 microM. ADP supported repair patch ligation after being converted into ATP by adenylate kinase in permeable cells.

Adenosine Diphosphate↗
PubMed1987

Different binding kinetics of Serratia 56K protease with plasma alpha 2-macroglobulin and chicken egg white ovomacroglobulin.

We recently reported that Serratia 56K protease is inhibited by plasma alpha 2 macroglobulin (alpha 2M) temporarily and by chicken egg white ovomacroglobulin (ovoM) continuously (Molla, A. et al. (1986) Infect. Immun. 53, 522-529). The inhibition of this protease is almost complete with ovoM whereas it is incomplete with alpha 2M, although these two macroglobulins show homology and many similarities. In the present study we determined the apparent numbers of binding sites and binding constants for the two macroglobulins by means of the fluorescence polarization method using FITC-labeled 56K protease. The time courses of complex formation of 56K protease with alpha 2M and ovoM were different; with ovoM it was complete within 5 min while with alpha 2M 150 min was required. Their apparent molecular volumes were also different; the fluorescence polarization value of the E/I complex was 18.7% larger with ovoM than with alpha 2M. The association constants obtained on Scatchard plot analysis with 56K protease and alpha 2M or ovoM were 0.33 X 10(7) M-1 and 1.09 X 10(7) M-1, respectively. One molecule of each of these macroglobulins binds 1.13 and 1.35 molecules of 56K protease, respectively. Upon E/I complex formation, an increase in amino groups due to proteolysis was noted in both cases, but more progressive proteolysis was observed in the case of alpha 2M. Furthermore, when the 56K protease was inactivated through the depletion of Zn atoms, complex formation did not occur.

Amino Acids↗
PubMed1987

Inhibition of microtubule polymerization by synthetic estrogens: formation of a ribbon structure.

Dienestrol, meso-hexestrol, and dl-hexestrol, synthetic nonsteroidal estrogens, were shown to be inhibitors of microtubule assembly in vitro using microtubule proteins isolated from porcine brains. The order of activity of the synthetic estrogens as inhibitors of microtubule assembly is: dienestrol greater than diethylstilbestrol greater than meso-hexestrol greater than dl-hexestrol greater than isodienestrol. The activity of dienestrol as an inhibitor was of the same order as that of (+)-griseofulvin, as determined by turbidity measurement. Electron microscopic observation revealed that twisted ribbon structures are formed from microtubule proteins in the presence of some synthetic estrogens (dienestrol, meso-hexestrol, and dl-hexestrol).

Animals↗
PubMed1987

Relationship between maturation of the skin and electrical skin resistance.

In 16 newborn infants (24 6-39 wk 6 days 830-3390 g) at ages between 0-70 days, the skin's electrical resistance was measured. Over 30 min we sequentially measured direct current resistance between two skin electrodes placed on the abdomen. The resistance was found to be low in very premature infants with gestation ages of 30 wk or less. It increased with both gestational age and postnatal age. In these infants, the resistance measured at 30 min during the first 4 days of life (3.4 +/- 0.3 K omega; mean +/- SD) was significantly less than that found at 20-70 days (8.8 +/- 1.2 k omega; p less than 0.001). The relationship between the infant's electrical skin resistance (y) and the gestational age (x) best fit the exponential formula: y = 7.42 X e0.24x X 10(-4) + 2.74. This formula shows that the electrical skin resistance increases exponentially during the last trimester. The measurement of electrical skin resistance is a quantitative method that can be utilized to evaluate the gestational age of infants.

Galvanic Skin Response↗
PubMed1987

Bleomycin-induced DNA synthesis in a cell-free system using a permeable mouse sarcoma cell extract.

To investigate factors involved in excision repair DNA synthesis, a soluble extract was prepared from permeable mouse sarcoma (SR-C3H/He) cells by homogenization and ultracentrifugation. DNA synthesis measured by using native calf thymus DNA as the template-primer and the extract as the polymerase source showed low activity. The DNA synthesis was enhanced more than ten-fold by the addition of an appropriate concentration of bleomycin, a radiomimetic DNA-damaging drug. Using selective inhibitors of DNA polymerases, it was shown that the DNA polymerase involved in the bleomycin-induced DNA synthesis was DNA polymerase beta. In addition to DNA polymerase beta, an exonuclease which converts bleomycin-damaged DNA into suitable template-primers for repair DNA synthesis appeared to be present in the permeable cell extract.

Animals↗
PubMed1987

Expression of simian virus 40 small t antigen in Escherichia coli and purification of the antigen.

A simian virus 40 (SV 40) DNA fragment encoding small t antigen was cloned in expression vector pUC8 for the purification of the antigen. The SV40 Hind III B fragment was inserted into the Hind III site of pUC8. A plasmid having the lacZ' and small t antigen genes in the same orientation was designated as pSVt. pSVt encodes the entire small t antigen and an extra 18 amino acids at the amino terminus of the antigen. E. coli transformed with pSVt produced hybrid small t antigen (22 kDa) which comprised about 6% of the total protein. The hybrid small t antigen reacted in immunoblot analysis with SV40-induced tumor-bearing hamster serum. Hybrid small t antigen was extracted from E. coli, and purified by preparative SDS-PAGE. The antigen was extracted from the gel using formic acid solution with high-yield. The gel-purified antigen showed the same antigenic reactivity as crude antigen.

Amino Acid Sequence↗
PubMed1987

[General mechanism of intratumor accumulation of macromolecules: advantage of macromolecular therapeutics].

Selective tumor targeting of anticancer agents is critically important in cancer chemotherapy. We previously found that a polymer-conjugated anticancer protein (neocarzinostatin; NCS), named smancs, accumulated more in tumor tissues than did NCS. In order to determine the general mechanism of this tumoritropic accumulation of smancs and other proteins, we used radioactive (51Cr-labeled) proteins with various molecular sizes (12-160 kDa) and other properties. In addition, we used dye-complexed serum albumin to visualize its accumulation in tumors of tumor-bearing mice. Many proteins progressively accumulated in the tumor tissues of the mice, and a ratio of the protein concentration in the tumor to that in the blood (T/B) of 5 was readily obtained within 6-48 h. A large protein like IgG required a longer time (72 h) to reach this value of 5. A T/B value of neither 1 nor 5 was achieved at a significant concentration with NCS, a representative small protein (12 kDa), at any time. We speculate that the tumoritropic accumulation of these proteins occurred because of hypervasculature and enhanced vascular permeability to even macromolecules, with little recovery through either blood vessels or lymphatic vessels from the tumor tissue. This accumulation of macromolecules in the tumor was also found after intravenous injection of dye (Evans blue) which was bound mostly to albumin. Thus, the albumin-dye complex was retained only in the tumor tissue for prolonged periods. There was little lymphatic recovery of macromolecules from tumor tissue. When this complex prepared in vitro was injected into the tumor and normal tissue, the latter tissue cleared it completely within 48 h whereas the tumor tissue retained most of it. The difference between the clearance from the tumor and that from normal tissue was based on the difference in lymphatic drainage of the two tissues. The present finding is of potential value in macromolecular tumor therapeutics and diagnosis. We propose this general mechanism of the behavior of macromolecules and lipids as EPR (enhanced permeability and retention) effect in solid tumor at microvasculature level.

Animals↗
PubMed1987

Facilitated internalization of neocarzinostatin and its lipophilic polymer conjugate, SMANCS, into cytosol in acidic pH.

The effects of environmental pH on the binding and cytotoxicity of the antitumor proteins neocarzinostatin (NCS) and SMANCS [copoly(styrene-maleic acid)-conjugated NCS] to cultured cells were studied by using their fluorescent-labeled derivatives (F-drugs). At 37 degrees C the binding of these drugs to HeLa cells was pH dependent: The amount of cell-bound drugs increased with an increase in the acidity of the medium. The pH-dependent change in the binding of the drugs was not as evident at 0 degree C. The cytotoxic action of these drugs was much more rapid at acidic pH compared with that at neutral or slightly alkaline pH. Furthermore, F-drugs could be utilized to probe the microenvironmental pH in Meth-A cells, in which the drug was located by the ratio of fluorescent intensities at 450 and 490 nm. The environment of the cell-bound F-drugs became acidic with incubation time at 37 degrees C but not at 0 degree C. Inasmuch as these drugs directly attack DNA, these results suggest that NCS and SMANCS are translocated across the membrane of acidic vesicles into the cytosol after endocytotic uptake. This hypothesis is also supported by the finding that NH4Cl and chloroquine protected HeLa cells against the cytotoxicity of the drugs. Data also showed that the hydrophobic polyanion conjugate SMANCS had a much greater cell binding (10 times) and more rapid internalization compared with NCS. Taken together, our results show that acidic pH of tumor tissue is preferable for effective binding and internalization into cytosol for NCS and SMANCS.

Ammonium Chloride↗
PubMed1987

[A case report of patient with advanced stomach carcinoma of linitis plastica type responding to multi-immunotherapy and chemotherapy].

Multiple-drug (OK-432, PSK and SPG) immunotherapy and chemotherapy provided remission of symptoms for 36 months in a patient aged 21 years suffering scirrhous gastric carcinoma associated with carcinomatous peritonitis in which direct infiltration to the pancreas, retroperitoneum and the left colon was observed. A remarkable improvement with time was observed by endoscopic and roentgenographic observation, and a substantial improvement was also observed in the NK-cell ratios of lymphocyte subsets of the OKT series in relation to immunologic parameters. A tumor necrosis factor [TNF]-like substance was thought to have been induced by multiimmunotherapy in this case.

Adenocarcinoma, Scirrhous↗
PubMed1987

[Superovulation-induced transient hyperprolactinemia in human in vitro fertilization and embryo transfer].

To examine the effects of transient hyperprolactinemia on in vitro fertilization and embryo transfer, 61 cycles in 50 euprolactinemic ovulatory women with irreparable tubal diseases were stimulated with clomiphene (CC) alone or CC and human menopausal gonadotropin followed by human chorionic gonadotropin (hCG). Serum prolactin (PRL) increased after hCG administration with peak values of 45.4 +/- 4.2 ng/ml on the day of laparoscopic oocyte aspiration. The highest serum estradiol (E2) concentration was found on the day before PRL peak and serum progesterone (P) began to increase after hCG injection concomitant with the PRL rise. The group having 50 ng/ml or more of PRL (34 cycles) had significantly higher levels of E2 during preovulatory and early luteal phase compared to those of the group having less than 50 ng/ml of PRL (27 cycles) but there was no significant difference between the P levels in the two groups. In the higher PRL group 72 (62.1%) of 116 collected oocytes were fertilized and 6 (20.0%) conceived. In the lower PRL group 45 oocytes (58.4%) of 77 were fertilized and 3 (12.5%) became pregnant. These data suggest that elevated serum PRL concentrations may have no effect on fertilization of oocytes in vitro or embryonic development.

Adult↗
PubMed1987

Changes in liver calcium content in relation to serum triiodothyronine (T3), thyroxine (T4) and T3/T4 ratio in rats treated with CCL4.

To evaluate the relation between liver calcium content and microsomal function in liver injury, we determined liver calcium content, serum triiodothyronine (T3), thyroxine (T4), T3/T4 ratio and serum glutamic pyruvic transaminase (SGPT) content in rats treated with CCl4. The T3/T4 ratio decreased from 1.9 to 1.2 at 6 hr after treatment, but elevated immediately to 3.2 at 36 hr after, and returned to normal at 54 hr after treatment. The calcium content increased from 27 micrograms/g wet weight to 448 micrograms/g wet weight 24 hr after treatment and decreased to normal 78 hr after treatment. The SGPT concentration showed the highest 12 hr after and returned to normal 72 hr after treatment. The calcium content was significantly correlated with T3 (r = -0.5, p less than 0.05). These results suggest that the increase and decrease in liver calcium content are closely related to the decrease and increase in T3 and T3/T4 ratio, respectively.

Alanine Transaminase↗
PubMed1987

[A case of a perforation indicative of early gastric cancer with various macroscopic findings and a collective review of the relevant Japanese literature].

A case of perforated early gastric cancer and a collective review of the relevant Japanese literature is reported. A 83-year-old woman with free air discovered by an abdominal X-ray, was referred to our hospital. On operating, a perforated ulcer was found within and lesions, indicative of a IIc + III type early gastric cancer. Macroscopically, there was an elevated lesion at the antrum of the stomach as well. Histologically, these lesions were connected and moderately differentiated adenocarcinoma. Another lesion was also found at the anterior wall and diagnosed as IIb type gastric cancer.

Adenocarcinoma↗