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Y Kikuchi

Publications and source records attributed to Y Kikuchi.

At least 865 records · Page 48Linked to original sources
PubMed1982

Inhibitory effect of L-homoarginine on murine osteosarcoma cell proliferation.

An organ-specific alkaline phosphatase inhibitor, L-homoarginine, at 44.5 mM concentration inhibited [3H]thymidine uptake by C3H/He mouse osteosarcoma (OS) cells, while L-arginine, L-phenylalanine, and glycine had little effect on the uptake. This inhibitory effect of L-homoarginine persisted even after the cells were washed free of the amino acid with fresh media. L-Homoarginine did not affect [3H]thymidine uptake by mouse myeloma MOPC 104E cells. In long-term culture, 22.3 mM L-homoarginine inhibited proliferation of OS cells. L-Arginine at the same concentration inhibited the proliferation to a lesser extent. On the other hand, L-phenylalanine and glycine did not affect in vitro proliferation of OS cells. When the same number of viable OS cells was inoculated s.c. after culturing the 24 hr with 44.5 mM L-homoarginine or L-arginine, the tumor growth in mice given injections of L-homoarginine (but not L-arginine)-treated cells was delayed markedly. Electron microscopic studies indicated that the inhibiting effect on OS cell proliferation was associated with a marked increase in lysosomal granules and a decrease in virus-like structures. Similarly, biochemical assay for acid phosphatase of cell homogenates demonstrated a 2-fold increase of activity in L-homoarginine-treated cells when compared to controls and L-arginine-treated cells. Thus, L-homoarginine inhibits proliferation and alkaline phosphatase activity of mouse OS cells and appears to increase acid phosphatase activity in synthesis of lysosomal granules.

Alkaline Phosphatase↗
PubMed1982

[Inhibitory effect of L-homoarginine on murine osteosarcoma cell proliferation].

An organ-specific alkaline phosphatase (AIP) inhibitor, L-homoarginine at 44.5 mM concentration inhibited 3H-thymidine uptake by mouse C3H/He osteosarcoma (OS) cells, while L-arginine, L-phenylalanine and L-glycine had little effect on the uptake. This inhibitory effect by L-homoarginine persisted even after the cells were washed free of the amino acid with fresh media. L-homoarginine did not affect 3H-thymidine uptake by mouse myeloma MOPC 104E cells. In the long-term culture, 22.3 mM L-homoarginine inhibited proliferation of OS cells. L-Arginine at the same concentration inhibited the proliferation to a lesser extent. On the other hand, L-phenylalanine and L-glycine did not affect in vitro proliferation of OS cells. When similar numbers of viable OS cells were inoculated s. c. after culturing with 44.5 mM L-homoarginine or L-arginine for 24 hr, the tumor growth in mice injected with L-homoarginine (but not L-arginine) treated cells was delayed markedly. Electron microscopic studies indicated that the inhibitory effect on OS cell proliferation was associated with a marked increase in lysosomal granules and a decrease in virus-like structures. Similarly, a biochemical assay of acid phosphatase (AcP) of the cell homogenates demonstrated two-fold increase of the activity in L-homoarginine treated cells when compared to the controls and L-arginine treated cells. Thus, L-homoarginine inhibits proliferation and AIP activity of mouse OS cells and appears to promote cell differentiation as evidenced by the increased synthesis of cytoplasmic granules and acid phosphatase activity.

Alkaline Phosphatase↗
PubMed1982

[Changes in the criteria for planned delivery in the National Defense Medical College Hospital with statistical analysis].

Planned deliveries have been attempted with the administration of prostaglandins E2 and F2 alpha since 1978. Eight hundred and eighteen prostaglandins-induced and 729 uninduced deliveries from January, 1978 to July, 1980 were statistically analyzed. The uninduced deliveries included 465 spontaneous and 264 stimulated labors. The cervical ripening was considered the basic requirement stimulated labors. The cervical ripening was considered the basic requirement for labor induction for the first year of study. However, spontaneous labor onset or the membranes rupture occurred before the induction in 52.4% of cases, where babies were large enough (3,052.6 +/- 33.4g, mean +/- SE, n = 154). Therefore, the cervical factor was excluded from the essential requirement for induction. Since the beginning of 1979, labor induction has been performed based on gestational age (38 weeks or more) and uterine fundal length (32cm or more). Laminaria tents were inserted into the unfavorable cervix the night before induction. Delivery time in the day, duration of labor, and birth weight of babies in the induced group were 2.04 +/- 0.18 p.m., 8.0 +/- 0.3 hours and 3,138.8 +/- 12.3g, respectively. Apgar scores and the amount of postpartum hemorrhage were not significantly different from those in the uninduced group. Similar results were obtained between the laminaria subgroup with unfavorable cervix and the non-laminaria subgroup with ripe cervix in the induced primigravidas.

Birth Weight↗
PubMed1981

The nucleotide sequence of the promoter and the amino-terminal region of alkaline phosphatase structural gene (phoA) of Escherichia coli.

The promoter and the amino-terminal region of phoA, the structural gene for alkaline phosphatase of Escherichia coli K12, was cloned by using a promoter cloning vector pMC1403. The nucleotide sequence of the cloned fragment has been determined. A sequence encoding the amino-terminal portion of mature alkaline phosphatase is found and it is preceded by a sequence encoding the signal peptide. The signal peptide consists of 21 amino acids; Met-Lys-Gln-Ser-Thr-Ile-Ala-Leu-Ala-Leu-Leu-Pro-Leu-Leu-Phe-Thr-Pro-Val-Thr-Lys-Ala. The translation initiation codon is GUG, which is preceded by the Shine-Dalgarno sequence GGAG. Upstream to these sequences, there is a typical procaryotic promoter. TATAGTC for the Pribnow box. Around the Pribnow box, there are several dyad symmetrical sequences, which may probably be concerned with the regulation of this gene.

Alkaline Phosphatase↗
PubMed1981

Effect of transpulmonary pressure on blood-flow velocity in pulmonary microvessels.

Flow velocity in the microvessels (30 to 90 micron in diameter) on the exposed lung surface of anesthetized bullfrogs was measured during positive lung inflation by means of a laser Doppler microscope. From the pulsatile flow-velocity contour generated by cardiac cycles, mean flow velocity (MV) and pulsatile amplitude (PA) were calculated and their alterations were studied as a function of transpulmonary pressure (TPP). At the lowest TPP of 1.3 +/- 0.8 cm H2O (mean +/- SD), MV and PA were 1.72 +/- 0.33 and 0.45 +/- 0.27 mm/sec, respectively. With moderate increments in TPP up to 2.8 +/- 1.3 cm H2O, both MV and PA increased, attaining maximum values of 2.11 +/- 0.42 and 0.69 +/- 0.28 mm/sec, respectively. But with further inflation they began to decrease, and there was a marked reduction or a complete arrest of blood flow at excessively high TPPs (6 to 9 cm H2O). With reduction of previously increased TPP, the alterations in MV and PA followed a pattern similar to that noted during elevation of TPP. There was an apparent hysteresis in both the MV-TPP and PA-TPP curves, most marked when excessively high TPP was applied.

Animals↗
PubMed1981

Studies on micronuclei time response and on the effects of multiple treatments of mutagens on induction of micronuclei.

Micronuclei time response and the effects of multiple treatments of mutagens on induction of micronuclei were studied. In the time-response investigation, mice were treated once with each of 5 mutagens, then killed at various times. The bone marrow was examined for the presence of micronucleated erythrocytes (MNEs). The maximal frequencies for MNEs occurred around 30 h post treatment for all mutagens tested. To examine the effects of multiple treatments, the frequencies of MNEs observed after a single- or a 5-treatment schedule were compared for 9 mutagens. Both treatment schedules were equally sensitive in detecting alkylating agents and spindle poisons, whereas the 5-treatment schedule was more sensitive for anti-metabolites. The 5-treatment schedule was particularly effective for detecting the anti-metabolites 5-fluorouracil and methotrexate, which require longer than 30 h to induce micronuclei (Maier and Schmid, 1976). These results suggest that it is practicable to sample at 30 h in the single-treatment schedule, and seem to support the usefulness of the 5-treatment schedule in screening tests.

Animals↗
PubMed1981

Methionine sulfoxide in the resilium protein of surf clams.

A high content of methionine sulfoxide was observed in the resiliums (internal hingeligaments) of surf clams. As no isolation procedure which might cause the oxidation of methionine to methionine sulfoxide was involved and the hydrolysis was carried out in vacuo, it is the first solid evidence for the presence of methionine sulfoxide as a constituent of natural protein.

Amino Acids↗
PubMed1981

The B region-associated antigens and MLR phenotypes in the Japanese inbred strains of rats.

Seven different alloantisera absorbed with red blood cells (RBC) from appropriate strains of rats detected a series of B cell alloantigenic specificities that could be divided into two groups, presumably coded for by at least two different closely-linked loci in the rat major histocompatibility complex (MHC), RT1. The one locus had two allele codes for a broad specificity and the other locus codes for a unique specificity that was found only in the restricted strains of rats that shared the same mixed lymphocyte reaction (MLR) phenotype. RBC-absorbed alloantisera were monitored against a panel of B cell fractions obtained from sixteen inbred strains. Two alloantisera, ACI anti-W and W anti-TO detected two broad specificities, into either of which all inbred strains tested were classified. Two broad RT1-B region-associated specificities were thus designated provisionally as Ba-1.1 and -1.2. Another five alloantisera detected four respective specificities which have a narrower strain distribution. Sixteen inbred strains were classified into one of five specificities detected by W and F344, F344 anti-SDJ, WKA anti-ACI, W anti-BUF and ACI anti-W absorbed with LEJ lymph node cells. Each specificity was designated provisionally as Ba-2.1, -2.2, -2.4, -2.6, -2.7, respectively. A complete association of Ba-2 specificities with MLR phenotype was observed. Antigenic specificities of Ba-2.2, -2.2 and -2.4 were all classified in a group of Ba-1.1 specificity, whereas Ba-2.6 and -2.7 specificities were associated with Ba-1.2 specificity. This relationship suggested a linkage disequilibrium between the two loci for the Ba antigens.

Animals↗