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Y Kikuchi

Publications and source records attributed to Y Kikuchi.

At least 451 records · Page 25Linked to original sources
PubMed1994

Stages in the development of the rat lung: morphometric, light and electron microscopic studies.

Ontogenic changes of the pulmonary epithelium of the rat, ranging from fetal day 15 to 1 hour after birth (21st day), were observed using light and electron microscopy as well as morphometric analysis on the area occupied by terminal segments of epithelial tubes or by alveolar sacs (ATETAS) in the terminal region of the lung. The development of the lung was classified into four stages. In the pseudoglandular period (fetal days 15 and 16), epithelial tubes lined by columnar epithelium were not yet associated with blood capillaries. The percentages occupied by ATETASs in the terminal region of the lung were 15.3% and 15.7%, respectively, on fetal days 15 and 16. In the precanalicular period (fetal days 17 and 18), blood capillaries began to appose to epithelial tubes lined by cuboidal epithelium. Small osmiophilic lamellar bodies (OLBs) emerged in cuboidal epithelial cells (type II cells) on day 18. The percentages occupied by ATETAS were 24.9% and 25.5%, respectively, on days 17 and 18. In canalicular period (fetal days 19 and 20), sac-like end segments showed progressive thinning of the epithelial linings, and the amount of interstital tissues markedly decreased. The epithelial cells differentiated into squamous, or type I cells, and type II cells containing OLBs. Extrusion of OLBs was recognized on day 20. Most of the capillaries were located close to the epithelial linings. The thickness of the blood-air barrier on day 20 was 10 times that of the adult. The percentages occupied by ATETAS were 35.8% and 38.5%, respectively, on days 19 and 20. In the terminal sac period (in neonate), the wall of terminal sacs showed a thin epithelial lining. Blood capillaries protruded close to the air-way surfaces. The thickness of the blood-air barrier was 3.5 times as thick as that of adult. The percentage occupied by ATETAS was 53.1% of the total terminal region of the lung. When the area occupied by ATETAS at a given day was compared to the area of the adult, the percentage on day 20 was approximately 60% of the adult value, whereas the percentage in neonates was 85%. This suggested that a remarkable transformation took place in ATETAS between day 20 and neonate. In addition to the four periods mentioned above, we also discussed the embryonic and alveolar periods in the development of the rat lung.

Animals↗
PubMed1994

Reappraisal of preoperative carcinoembryonic antigen levels as a prognostic factor in resectable colorectal cancer.

Preoperative carcinoembryonic antigen levels in sera were measured in 124 cases of primary colorectal cancer, and their usefulness as a prognostic factor were evaluated. There were no significant differences in the CEA levels with regard to age, sex, size of the primary tumor, histological differentiation, peritoneal dissemination or DNA ploidy, but CEA levels were significantly higher in patients with liver metastasis. By using Cox proportional hazard model, the most significant discriminant in prognosis was liver metastasis, followed by preoperative CEA level, depth of invasion and DNA ploidy pattern. Preoperative CEA measurements were applied as a parameter of biological behavior of colorectal cancer in the follow-up course.

Adult↗
PubMed1994

[Study of in vitro cancer sensitivity of anticancer drugs by SDI (succinate dehydrogenase inhibition test)].

To clarify the effect of fibroblast mixture in in vitro sensitivity test using SDI method. I have investigated the influence of fibroblast on the anticancer sensitivity test in a colon cancer cell line. The anticancer drugs, such as MMC (mitomycin C), CDDP (cisplatin) and 5-FU (5-fluorouracil) were contacted with colon cancer cells at 8 different concentrations on the intervals from 24 to 168 hours. The drug sensitivity of cancer cells in mixture of fibroblast was influenced by the kind of anticancer drugs, sensitivity of fibroblast itself, and the difference of sensitivity of cancer cell and fibroblasts. With the increase of percentage of fibroblast, the sensitivity of cancer cells became almost equivalent to that of fibroblast in 5-FU. But the sensitivity was not influenced by MMC or CDDP. And the difference of sensitivity was within about 27% by using 5-FU when the cancer cell ratio is 50%. Drug sensitivity of cancer cells was greatly influenced by drug concentration and contact time. Although the optimal contact time of sensitivity test depended on the kinds of drugs, 72 hours was considered to be optimal.

Cisplatin↗
PubMed1994

[Potentiation of cisplatin sensitivity of cisplatin-resistant human ovarian cancer cell lines by L-buthionine-S,R-sulfoximine].

We established two human ovarian cancer cell lines (KK and MH) from the ascites of patients who did not respond to cisplatin (CDDP)-based combination chemotherapy. These cell lines showed higher resistance to CDDP in vitro than HRA cells which were established previously in our laboratory, and also have cross resistance with its analogues. The amount of intracellular glutathione (GSH) in these cells correlated with the degree of resistance to CDDP and was high, but the intracellular platinum (Pt) uptake was unchanged. Preincubation with L-buthionine-S,R-sulfoximine (BSO) reduced cellular GSH in these cells to 9-25%, while the Pt uptake remained unchanged. When the CDDP-resistant KK and MH cells were incubated in the presence of 10 microM BSO, they were sensitized to CDDP and its analogues showing a decrease to 79-38% in the IC50 values. On the basis of these results, we conclude that GSH may be involved in the mechanisms of resistance to CDDP and its analogues in the KK and MH cells.

Adenocarcinoma↗
PubMed1994

[Treatment and prognostic factors of stage I and II non-Hodgkin's lymphoma].

In order to assess prognostic factors and therapeutic methods, 104 patients (aged 6 to 89; mean age 57.4; male 68, female 36; stage: I 45, II 59) with clinical stages I and II non-Hodgkin's lymphoma treated at our department between 1977 and 1991 were reviewed. Factors, such as sex, age, clinical stage, primary site, presence of general symptoms, pathology, tumor size, LDH and therapeutic methods (radiotherapy alone; initial radiotherapy plus chemotherapy; initial chemotherapy plus radiotherapy) were calculated by univariated analysis to determine important factors influencing the survival. The survival of patients with symptoms and large tumors (more than 70 mm) was shorter than that of those without symptoms and with small tumors (5 years survival: symptom B 17.9%, A 68.2%, p < 0.001; tumor more than 70 mm 44.0%, less than 70 mm 67.1%, p < 0.05). Regarding therapeutic methods, radiotherapy alone achieved a 5-year survival rate of 37.1%; initial radiotherapy plus chemotherapy had 64.6% and initial chemotherapy plus radiotherapy 78.5%, but a significant difference was noticed only between radiotherapy alone and initial chemotherapy plus radiotherapy (p < 0.001). These results suggest that important factors influencing the survival are presence of general symptoms, tumor size and therapeutic methods.

Adolescent↗
PubMed1994

[Clinical significance of flow cytometric DNA analysis in metastatic lymph node of colorectal cancer].

Significance of flow cytometric DNA analysis in metastatic lymph nodes for assessing malignant potential of colorectal cancer was investigated using paraffin-embedded materials of primary lesions and metastatic lymph nodes from 65 patients who had been treated between 1975 and 1990. The DNA ploidy patterns of metastatic nodes were identical in 61.5% with those of primary lesions. Diploid cancers were significantly more frequent in metastatic nodes than in primary lesions. There were significantly more aneuploid cancers in proximal nodes than in distant nodes. There was no relation between ploidy patterns in primary lesions and survival. However, a significant relation was found between ploidy patterns in metastatic nodes and survival. Diploid cancer in metastatic nodes had a significantly better survival than aneuploid cancer, in all patients as well as those with curative resection. In patients with stage III and in those with the same depth of invasion, the survival rate of diploid cancer in metastatic nodes was significantly higher. There was no correlation between ploidy patterns in metastatic nodes and clinicopathological variables in primary lesions, such as histological type, depth of invasion, nodal involvement, peritoneal or hepatic involvement and stage. These results suggest that nuclear DNA content in metastatic lymph nodes may be a prognostic indicator in colorectal cancer with nodal involvement.

Colorectal Neoplasms↗
PubMed1994

Gallbladder emptying to endogenous and exogenous stimulation in chronic pancreatitis patients.

OBJECTIVES: The present study was designed to analyze the underlying mechanism of gallbladder motor disturbance in chronic pancreatitis patients. METHODS: Gallbladder emptying to endogenous (oral test meal, Daiyan 13 g) and exogenous stimulation (iv cerulein, 30 ng/kg for 5 min) was examined by real-time ultrasonography in 12 patients with chronic pancreatitis and 10 normal subjects (controls). Plasma cholecystokinin levels during the endogenous stimulation were measured by bioassay. RESULTS: In chronic pancreatitis patients compared with controls, the fasting gallbladder volume was significantly increased (29.5 +/- 2.2 vs. 21.5 +/- 2.8 ml), whereas the gallbladder emptying (percent change of the basal volume) to oral test meal was significantly decreased. Neither cholecystokinin secretion induced by the test meal, nor the gallbladder emptying response to intravenous cerulein, differed significantly between the two groups. However, when chronic pancreatitis patients were divided according to pathogenesis, it became clear that gallbladder emptying to intravenous cerulein was significantly greater in patients with alcoholic chronic pancreatitis than in patients with idiopathic pancreatitis. CONCLUSIONS: Gallbladder emptying during the intestinal phase is generally reduced in patients with chronic pancreatitis, but gallbladder responsiveness to exogenous stimulation might be heterogeneous according to the pathogenesis.

Adult↗
PubMed1994

[Anti-tumor activity of zinostatin stimalamer (YM 881) examined by human hepatoma cells in vitro and VX2 liver tumor in vivo].

Anti-tumor activities of zinostatin stimalamer (YM 881) were examined using human hepatoma cell lines (SK-Hep1 and HuH 2) and VX2 liver tumor-bearing rabbits. YM881 inhibited the growth of human hepatoma cells in a dose-dependent manner. The IC50 values of YM881 against SK-Hep 1 and HuH 2 cells were 6.7 and 27 mM, respectively. In VX2 tumor-bearing rabbits, administration of YM 881 suspended in iodinated fatty acid ethylesters of poppyseed oil (YM 881/Lipiodol suspension, 0.2 mg/0.2 ml/body) into the hepatic artery showed significant (p < 0.01, vs sham-operated and Lipiodol-treated groups) inhibitory effects on the growth and pathological changes 1 and 2 weeks after administration. On the other hand, Lipiodol (0.2 ml/body) showed a tendency to inhibit the growth of VX2 tumor (p < 0.1, vs sham-operated group) 1 week after administration, but it showed only moderate effects on the VX2 tumor growth 2 weeks after administration. Minimal necrosis was observed 1 and 2 weeks after administration of Lipiodol, and these pathological findings were similar to those in the sham-operated group. From the present study, it is suggested that YM 881/Lipiodol suspension showed the anti-tumor activity against VX2 tumor-bearing rabbits, presumably due to the inhibition of the growth of hepatoma cell by YM 881 per se. On the other hand, Lipiodol is considered to augment the anti-tumor activity by maintaining high YM881 concentrations in tumor tissue.

Animals↗
PubMed1993

Artificial self-cleaving molecules consisting of a tRNA precursor and the catalytic RNA of RNase P.

We synthesized two types of chimeric RNAs between the catalytic RNA subunit of RNase P from Escherichia coli (M1 RNA) and a tRNA precursor (pre-tRNA); one had pre-tRNA at the 3' side to the M1 RNA (M1 RNA-pre-tRNA). The second had pre-tRNA at the 5' side of the M1 RNA (pre-tRNA-M1 RNA). Both molecules were self-cleaving RNAs. The self-cleavage of M1 RNA-pre-tRNA occurred at the normal site (5'-end of mature tRNA sequence) and proceeded under the condition of 10 mM Mg2+ concentration. This reaction at 10 mM Mg2+ was an intramolecular reaction (cis-cleavage), while, at 40 mM and 80 mM Mg2+, trans-cleavage partially occurred. The self-cleavage rate was strictly affected by the distance between the M1 RNA and the pre-tRNA in the molecule. The self-cleavage of pre-tRNA-M1 RNA occurred mainly at three sites within the mature tRNA sequence. This cleavage did not occur at 10 mM Mg2+. Use of M1 RNA-pre-tRNA molecule for the in vitro evolution of M1 RNA is discussed.

Animals↗
PubMed1993

Modulation of sensitivity of human ovarian cancer cells to cis-diamminedichloroplatinum(II) by 12-O-tetradecanoylphorbol-13-acetate and D,L-buthionine-S,R-sulphoximine.

The ability of 12-O-tetradecanoylphorbol-13-acetate (TPA) and D,L-buthionine-S,R-sulphoximine (BSO) to modulate cis-diamminedichloroplatinum(II) (CDDP) sensitivity was investigated in human ovarian cancer cell lines sensitive (KF) or with intrinsic resistance (KK and MH) to CDDP. The KK and MH cell lines were derived from ascites of patients with clear-cell carcinoma and serous cystadenocarcinoma of the ovary who both showed clinical resistance to CDDP. The CDDP IC50 value of KK and MH cells was about 4.6- and 10.2-fold higher than that of KF cells. PKC activities in the cytosol and membrane of KK and MH cells were also about 4- to 5-fold higher than those of KF cells. Proliferation of KF, KK and MH cells was inhibited in a dose-dependent manner by TPA. The membrane PKC activities in the KF cells were rapidly activated and down-regulated 24 hr after exposure to TPA, while those in the KK and MH cells were not down-regulated even after exposure to TPA for 24 hr, suggesting that the membrane form of PKC may be involved in the intrinsic resistance. Continuous exposure to 10 nM TPA for 5 days significantly reduced the CDDP sensitivity of KF and KK cells, while exposure to 10 nM TPA for 1 hr significantly elevated that of KK and MH cells. Interestingly, 1-hr exposure to 1 microM TPA induced CDDP-resistance in KK cells. Such changes in CDDP sensitivity by TPA seemed to be linked with those of cellular PKC activity, i.e., when the CDDP sensitivity was reduced by TPA, the cellular PKC rose.(ABSTRACT TRUNCATED AT 250 WORDS)

Buthionine Sulfoximine↗
PubMed1993

Different target-site specificities of the hairpin ribozyme in cis and trans cleavages.

The hairpin ribozyme cleaves a phosphodiester bond at the 5' side of a 5'GUC3' sequence of an RNA with high efficiency. An RNA having a 5'GUA3' sequence instead of the GUC sequence is a poor substrate for this ribozyme. Here, we show that this is indeed so in a trans-acting ribozyme system, but in a cis-acting ribozyme system this ribozyme cleaves the 5' side of a GUA sequence as efficiently as the wild-type cleaves the GUC sequence. One base substitution in the ribozyme also affected the target-site specificity in the cis-acting system.

Base Sequence↗
PubMed1993

Induction of metallothionein in a human astrocytoma cell line by interleukin-1 and heavy metals.

The effects of cytokines and heavy metals on the expression and localization of metallothioneins (MTs) within U373MG astrocytoma cells were analyzed by using indirect immunofluorescence using a monoclonal anti-MT antibody (MT45). IL-1, CdCl2 (50 microM) or ZnCl2 (500 microM) remarkably augmented intracellular MT levels, whereas IL-6 or 10 microM of ZnCl2 showed no inducing activity. From 24 to 48 h after the addition of CdCl2 or IL-1, immunoreactive MTs were found in the cytoplasm and the nucleus. After 72 h, immunoreactive MTs accumulated in a granular form near the cell surfaces in the presence of CdCl2 (50 microM) or IL-1 plus ZnCl2 (10 microM). However, this accumulation was not observed when only IL-1 was added. Thus, Zn2+ facilitated the appearance of the granular form of immunoreactive MTs at a concentration where they do not induce MTs by themselves.

Astrocytoma↗
PubMed1993

Enhancement of antiproliferative effect of cis-diamminedichloroplatinum(II) by clomiphene and tamoxifen in human ovarian cancer cells.

In this study, we examined antiproliferative effect of clomiphene and tamoxifen alone and their combined effect on cis-diamminedichloroplatinum(II) (CDDP) by using human ovarian cancer cells (KF, KK, and MH cells) with different sensitivity to CDDP and MCF-7 cells derived from human breast cancer. KF, KK, and MH cells did not have estrogen receptor while MCF-7 cells had it. The KF cells were most sensitive to CDDP followed by KK, MCF-7, and MH cells. Similarly, the KF cells among three human ovarian cancer cell lines were most sensitive to clomiphene and tamoxifen alone. The MCF-7 cells had similar high sensitivity to both clomiphene and tamoxifen. When effects of clomiphene and tamoxifen on the protein kinase C (PKC) activity in the cancer cells were examined, the degree of inhibition of the PKC activity in the KF cells by clomiphene and tamoxifen was most marked and that by clomiphene was followed by those by KK, MH, and MCF-7 cells, while that by tamoxifen was, in increasing order, MH, MCF-7, and KK cells. Analyses of effects of clomiphene or tamoxifen on concentrations of CDDP required for 50% inhibition of cell proliferation (IC50) revealed that although the combined effects, in the KF and KK cells were only marginal, marked enhancement of antiproliferative effects of CDDP on the MH cells resistant to CDDP was obtained. When 5 x 10(6) cells were incubated with 100 microM CDDP for 3 hr, uptake of CDDP by MCF-7 cells was lowest, followed by MH, KK, and KF cells. The CDDP uptake by KF and KK cells was increased about 30-40% in the presence of clomiphene or tamoxifen. The CDDP uptake by the MH cells in which most marked enhancement of antiproliferative effect of CDDP was observed by a combination with clomiphene or tamoxifen was increased about 80-90% in the presence of clomiphene or tamoxifen. These results suggest that not only tamoxifen but also clomiphene can potentiate antiproliferative effect of CDDP in the ER-negative CDDP-resistant cancer cells by enhancing the CDDP uptake.

Adenocarcinoma↗
PubMed1993

Inhibitory effects by oral administration of ginsenoside Rh2 on the growth of human ovarian cancer cells in nude mice.

Recently two new compounds, ginsenosides Rh1 and Rh2, have been isolated from an ethanol extract of the processed root of Panax ginseng CA Meyer, and Rh2 (but not Rh1) has been found to cause growth inhibition of cultured B16 melanoma cells. We have also demonstrated that Rh2 caused inhibition of cultured human ovarian cancer cell (HRA) proliferation. The effect of oral administration of Rh2 on tumor growth and survival of nude mice bearing HRA cells was examined. Nude mice were inoculated subcutaneously in the right flank with 10(6) HRA cells. After 7 days of tumor inoculation 2 mg/kg cis-diamminedichloroplatinum(II) (cisplatin) was administered intraperitoneally once a week for 5 weeks. In Rh2-treated groups. Rh2 was dissolved in absolute ethanol, adjusted with distilled water to 1, 15, and 120 microM, and 0.4 ml of each concentration was administered orally by canula every day for 90 days, from the next day of tumor inoculation. The tumor volume, hematocrit and body weight were measured every week. On days 56 and 63 after tumor inoculation, the tumor volumes in all groups treated with Rh2 were significantly less than those in an ethanol-treated control group and also in cisplatin treated group. After 70 days, the tumor growth in nude mice treated with 15 microM and 120 microM Rh2 was significantly inhibited compared to that in a cisplatin treated group as well as a control group. Consequently, the survival of nude mice treated with 15 microM and 120 microM Rh2 was also significantly prolonged, compared to that of cisplatin treated mice. No toxic effects were observed in any of the mice.

Administration, Oral↗
PubMed1993

Primary ovarian lymphoma. A case report.

A 44-year-old woman with stage IV non-Hodgkin's lymphoma (NHL) of the left ovary is described. She had an extended hysterectomy and bilateral salpingo-ophorectomy and thereafter received six courses of combination chemotherapy (cyclophosphamide, adriamycin, vincristine and predonisolone; CHOP). The patient is well with no evidence of recurrence at 12 months after surgery. The literature on primary ovarian lymphoma is reviewed.

Adult↗
PubMed1993

NADPH-diaphorase activity in neurons of the mammalian pancreas: coexpression with vasoactive intestinal polypeptide.

BACKGROUND: To provide a morphological basis for understanding the role of nitric oxide in the pancreas, the present study was designed to clarify the localization and distribution of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) activity, a marker of NO synthase, in the pancreas of several mammalian species, including humans. METHODS: NADPH-d activity was examined in the rat, guinea pig, dog, and human pancreas by histochemistry. In addition, the possibility of coproduction of NO and vasoactive intestinal polypeptide (VIP) was investigated by a combined use of histochemistry and immunohistochemistry. RESULTS: In the pancreas, NADPH-d activity was localized in nerve fibers, nerve cell bodies, and the vascular endothelium. Nerve fibers with the enzyme activity were chiefly distributed in the exocrine pancreas and showed species differences in the distribution. Nerve fibers stained for NADPH-d were also observed in the endocrine pancreas, but the enzyme activity was not detected in the islet cells. Part of the nerve fibers and nerve cell bodies coexpressed NADPH-d activity and VIP-immunoreactivity. CONCLUSIONS: These results suggest that NO may act as a neuronal mediator and an endothelium-derived relaxing factor and may physiologically interact with VIP in the mammalian pancreas.

Amino Acid Oxidoreductases↗