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Biomedical subjects

Y Kikuchi

Publications and source records attributed to Y Kikuchi.

At least 487 records · Page 27Linked to original sources
PubMed1993

Fetal liver micronucleus assay in mice of 5-fluorouracil and related compounds.

The cytogenetic effects of 5-fluorouracil (5-FU), 1-hexyl-carbamoyl-5- fluorouracil (HCFU) and 1-(2-tetrahydrofuryl)-5-fluorouracil (TF) were examined with the fetal liver micronucleus assay in mice. The frequencies of micronucleated polychromatic erythrocytes (MNPCEs) in fetal liver peaked at 27, 24 and 27 h, respectively, after single intraperitoneal injections into pregnant mice on day 13 of gestation. The highest frequency of MNPCEs by 5-FU treatment in fetal liver was 13.6%, whereas the frequency in maternal bone marrow was only 0.4%. The micronucleus frequency and the number of micronuclei per individual polychromatic erythrocyte were clearly dose-dependent. These results suggest that the micronucleus test in fetal liver has particular advantages compared to maternal bone marrow for evaluating the cytogenetic effects of 5-FU and related compounds after a single treatment. The cytogenetic effect was ranked 5-FU = HCFU > TF, in both a time-course study and a dose-response study of micronucleus distribution.

Animals↗
PubMed1993

Investigation and research on classification of productive skills (2): Cluster structure of productive skills in the car manufacturing industry.

A survey was conducted at a production facility to study the categories of productive skills. In August 1991, a questionnaire survey was given to skilled workers of a car manufacturing company. The number of valid responses was 1,215. The survey items included 133 items in the following three areas: nature of productive skills, human functions and vocational ability necessary for the work, and working conditions. The survey results were analyzed by cluster analysis to verify the hypothesis that skills can be classified based on two axes--sensory motor and intellectual management. Moreover, the analysis results clarify that the structure of "nature of productive skills" in car manufacturing can be divided into maintenance, processing, information analysis and transmission, and parts assembly. The results also show that the internal structure of intellectual management skills, which had been unknown up to this point, consists of five skill clusters: field of technical knowledge, operation of controlling equipment, preparation abilities, analysis and judgment abilities, and measurement.

Automobiles↗
PubMed1993

[Establishment and characterization of a CA125-producing human ovarian clear cell carcinoma cell line].

A human ovarian cancer cell line designated "KK" was established from ascites of a patient with ovarian clear cell carcinoma. This cell line was grown for more than 2 years and over 140 passages in medium RPMI1640 containing 10% FCS. Doubling time of this cell line at passage 70 was approximately 4 days and saturation density was 1.1 x 10(5)/cm2. Plating efficiency was approximately 23%. Chromosome analysis revealed aneuploidy with a model number of 67. PAS-positive substances were present in the cytoplasm. CA125 and SLX were detected in both the original tumor and the cultured cells. This cell line is less sensitive to cisplatin than KF cells and IC50 was 0.95 microM.

Adenocarcinoma, Clear Cell↗
PubMed1993

[Establishment of a cisplatin-resistant human ovarian cancer cell line].

A human ovarian cancer cell line designated "MH" was established from ascites of a patient with ovarian serous cystadenocarcinoma treated with cisplatin. This cell line was grown for more than 2 years and over 100 passages in medium RPMI1640 containing 10% FCS. The cell doubling time, saturation density and plating efficiency was approximately 6.3 days, 5.5 x 10(4)/cm2, and 42%, respectively. Chromosomal analysis revealed aneuploidy with a modal number of 72 and 14-19 types of marker chromosomes. CA125 was detected in both the original tumor and the cultured cells. This cell line is cisplatin-resistant (IC50: 3.28 microM) and has high protein kinase C activity.

Adult↗
PubMed1993

[Inhibitory effects of oral administration of ginsenoside Rh2 on tumor growth in nude mice bearing serous cyst adenocarcinoma of the human ovary].

We examined the inhibitory effect of the oral administration of ginsenoside Rh2 (Rh2) on tumor growth in nude mice bearing human ovarian cancer cells (HRA). In the first experiment, it was revealed that daily administration of 30 microM Rh2 significantly inhibited tumor growth. In the second experiment, therefore, various concentration of Rh2 (1, 15, 30, 60, 120 microM) were administered every day for 91 days, beginning the day after tumor inoculation. Treatment with Rh2 resulted in a remarkable retardation of the HRA cell tumor growth. In particular, tumor growth in mice treated with 15, 30 and 120 microM Rh2 was significantly inhibited, compared to that in CDDP treated mice as well as in untreated mice. Consequently, 50% survival in nude mice treated with 15, 30 and 120 microM Rh2 was significantly prolonged, compared to that not only in untreated mice but also in CDDP treated mice. No side effect was observed in any mice treated with Rh2. Red ginseng containing Rh2 has been used exclusively, orally administered. In the present study, we considered that oral administration of Rh2, which is a component of red ginseng, has strong inhibitory effects on human ovarian cancer cell growth in nude mice.

Administration, Oral↗
PubMed1993

[Changes in the blood flow in celiac artery and superior mesenteric artery after stellate ganglion block].

We evaluated the effect of stellate ganglion block (SGB) on the blood flow of celiac artery (CA) and superior mesenteric artery (SMA) by using the ultrasonic pulse Doppler technique. The subjects were 15 healthy volunteers (14 males, one female; average 26 years old; 22-38). Right C7-SGB was performed using 5 ml of 1% mepivacaine at the 7th cervical process. Blood pressure, heart rate, mean blood flow velocity and diameter in CA and SMA, were measured after 5 minute rest, before and after SGB. To measure the flow velocity and the diameter of vessels, ultrasonic diagnostic equipment SSA-270A or SSA-260A (Thoshiba CO, Ltd.) with convex electric-phased 3.75 MHz, probe was used. Doppler shiftgrams of the CA and SMA were recorded. Then, we calculated their flow volume and sectional area of vessels. In CA mean blood flow velocity tended to decrease (P < 0.05) and both flow volume and sectional area of vessels tended to increase (P < 0.001). In SMA, mean flow velocity tended to decrease (P < 0.05) and sectional area increased (P < 0.001). But flow volume did not show significant change. Our results indicate that right C7-SGB leads to an increase in the blood flow of CA.

Adult↗
PubMed1993

[Study on clinical application of multiple fractions per day radiation therapy with concomitant boost technique for esophageal cancer].

A continuous multiple fractions per day irradiation (MFD) using twice-a-day (BID) fractionation in the similar form of concomitant boost was devised for the treatment of advanced esophageal cancer. From Oct. 1985 to July 1991 60 patients were entered in this clinical trial and were compared with 64 patients who were treated with conventional once-a-day irradiation (CF) from July 1977 to July 1989 in survival, local control, acute and late effect. The altered fractionation schedule employed continuous concomitant boost technique with reduced field for primary site being irradiated twice-a-day. Daily fraction size were 2 Gy with large field including primary and regional lymphatics and 1.1, 1.15 and 1.2Gy with concomitant boost. Total dose of 62, 63 and 64Gy were administered in 40 fraction for 5 weeks. Acute reaction caused radiation mediastinitis, pneumonitis and esophagitis, but severe injury which interrupted treatment did not occur. Late reaction consisted of 8 radiation induced stricture [RIS] (13.3%), 2 radiation induced pericarditis(3.3%) and 1 bronchial ulcer(1.7%) in MFD. Particularly, RIS in 3.2Gy/2f/day group of MFD developed with higher frequency than in CF and another daily fraction size. Patients treated with CF and MFD experienced 5 year loco-recurrence free survival of 27.3% and 57.2% respectively (P < 0.001), which translated into 5 year cause-specific survival 13.9% and 31.5%, respectively (P < 0.05). Significant advantage in adjusted local-recurrence free survival using multivariable analysis was shown (P < 0.005). Also, a border line advantage in adjusted survival using clinical stage is now appearing in MFD as a consequence of the increased local control rate. There was no significant difference in survival and local-recurrence free survival among each daily dose groups. We concluded that our regimen of MFD using optimal daily dose of 3.15Gy/2f/day with continuous concomitant boost technique resulted in improved local control and survival rate of treatment of esophageal cancer without severe late reaction.

Adult↗
PubMed1993

[A case report of unroofed coronary sinus with repeated congestive cardiac failure].

We reported a 64-year-old woman with frequent cardiac failure due to unroofed coronary sinus complicated with tricuspid regurgitation (TR). We performed direct suture closure of unroofed coronary sinus and tricuspid annuloplasty with a Carpentier ring (34 T). Immediately after the operation, large amount of pleural effusion accumulated owing to acute left ventricular failure. That cause consists in the scarcity of the left ventricular volume, which was depending on the much left-to-right shunt volume through the unroofed coronary sinus. But her general condition was recovered from acute left ventricular failure for administration of catecholamine, digitalization, and urinative. We think that the echocardiography is valuable to investigation of the existence of unroofed coronary sinus, especially complicated with TR.

Coronary Vessel Anomalies↗
PubMed1993

Dependence of baroreceptor-mediated sympathetic outflow on biventricular assist device driving frequency.

To investigate the drive condition of the artificial heart from a neurophysiological point of view, the dynamic transduction characteristics of the baroreflex system were analyzed by means of sympathetic neurograms. Two pneumatically actuated ventricular assist devices were implanted as biventricular bypasses (BVBs) in adult mongrel dogs to compare the natural heart circulation and prosthetic circulation. After BVB pumping was initiated, the natural heart was electrically fibrillated. Renal sympathetic nerve activity (RSNA) was recorded to analyze sympathetic outflow. Coherence function between the arterial pressure and RSNA was calculated to evaluate the linearity of the baroreflex system. The largest peak coherency was observed when BVB was driven at the frequency of natural heart beat prior to electrical fibrillation, which suggests that the baroreflex system shows the largest linearity at this frequency. These results suggest the possibility that the natural heart beat frequency is the setting frequency at which the baroreflex system transfers the hemodynamic rhythm to the sympathetic outflow.

Animals↗
PubMed1993

[S-phase fraction and malignant potential in DNA diploid colorectal cancer].

Patients with DNA diploid tumor have a significantly longer survival than those with DNA aneuploid in colorectal cancer, but some patients with diploid tumor show poor survival. For assessing malignant potential in diploid colorectal cancer, flow cytometric analysis of S-phase fraction (SPF) was investigated using paraffin-embedded materials from 79 carcinoma patients who had been treated from 1971 to 1989. There was no significant correlation between SPF and clinicopathological factors (such as sex, tumor size, tumor location, macroscopical type, depth of invasion, node metastasis, peritoneal dissemination, liver metastasis and clinical stage). Mean SPF was significantly higher in poorly differentiated type carcinomas than in well differentiated type carcinomas. Patients with higher SPF had a tendency to poorer survival than those with lower SPF. From these results, it was concluded that SPF represents histological differentiation and that SPF may be a prognostic indicator, in diploid colorectal cancer.

Carcinoma↗
PubMed1993

[Interleukin-6 production in endometriosis].

The purpose of this study was to assess whether endometriotic implants of endometriosis could produce Interleukin (IL)-6. IL-6 was measured by means of an enzyme-linked immunosorbent assay (ELISA) in 21 patients with endometriosis of stage IV according to R-AFS classification of endometriosis. The tissues obtained from endometriotic implants were incubated for 24 hours and all their supernatants (n = 8) were positive for IL-6 and the mean level of IL-6 was approximately 30pg/ml per 1mg tissue dry weight. The level of IL-6 in the supernatant did not correlate with the serum estradiol level or with positivity against autoimmune antibodies in patients with endometriosis before surgery. The cultured stromal cells obtained from endometriotic implants were immunohistochemically positive for rabbit antihuman IL-6 polyclonal antibodies. IL-1 alpha (0.5ng/ml) and lipopolysaccharide (LPS) (10 micrograms/ml) caused a 50% and a 130% increase respectively, in IL-6 production in untreated cells (p < 0.01) of 24-hour culture (n = 3). On the other hand, estradiol, progesterone and danazol apparently had no effect on IL-6 production. The serum IL-6 levels of patients with myoma uteri (n = 10) were significantly (p < 0.05) enhanced after surgery, while those of patients with endometriosis (n = 14) declined after surgery. The anti IL-6 antibodies between 10ng/ml and 100ng/ml inhibited cell growth 20% (p < 0.05), while IL-1 alpha (0.5ng/ml) inhibited cell growth 50% (p < 0.01) in a 5 day cell culture (n = 6).(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies↗
PubMed1993

[Antitumor effect of PSK and its combined effect with CDDP on ovarian serous adenocarcinoma-bearing nude mice].

Although the antitumor effect of PSK can be increased by potentiating the immune functions of PSK in tumor-bearing hosts, the mechanisms of its action are not fully understood. In this study, we examined the antitumor effect and CDDP combined effect of oral administration of PSK on nude mice bearing a human ovarian cancer cell line (KF cells). 1. PSK was observed to have a significant antitumor effect in tumor-bearing nude mice and subsequently to bring about an increase in the survival rate and prolongation of the life span. 2. The antitumor effect of CDDP was (but not significantly) enhanced by oral administration of PSK and the prolongation of the life span of the tumor-bearing nude mice was obtained. 3. Six weeks after tumor inoculation, no significant natural killer (NK) cell activity in spleen cells from untreated nude mice was observed. However, when PSK (100 mg/kg but not 500 mg/kg) was given every other day, significant NK activity was induced. 4. The serum immunosuppressive acid protein (IAP) value in nude mice treated with PSK alone was significantly higher than that in nude mice treated with a combination of PSK (100 mg/kg) and CDDP. These results suggest that CDDP prevents the increase in serum IAP that occurs when PSK is used and that consequently combinations of PSK and CDDP result in augmentation of antitumor effects.

Animals↗
PubMed1992

Hyperprocessing of tRNA by the catalytic RNA of RNase P. Cleavage of a natural tRNA within the mature tRNA sequence and evidence for an altered conformation of the substrate tRNA.

In the transposon copia-related retrovirus-like particles of Drosophila, a 39-nucleotide-long fragment from the 5'-region of Drosophila initiator methionine tRNA (tRNA(iMet)) is used as the primer for copia minus-strand reverse transcription. This primer tRNA(iMet) fragment is thought to be produced by cleavage within the mature tRNA(iMet) sequence. We call this cleavage hyperprocessing. We have previously reported that catalytic RNA of RNase P from Escherichia coli (M1RNA) cleaves the synthetic tRNA(iMet) precursor in vitro at several sites within the mature tRNA sequence. Based on this result, we proposed a model for formation of the primer tRNA fragment involving RNase P. Here we show that natural tRNA(iMet) prepared from Drosophila adult flies can be cleaved by M1RNA. Using mutant tRNA(iMet) substrates, we also show that these cleavages are dependent on the occurrence of an altered conformation of the tRNA substrate. This is evidence that a tRNA can exist in aqueous solution at least in part in an altered conformation.

Animals↗
PubMed1992

Molecular cloning and expression of the human interleukin 5 receptor.

Human interleukin 5 (IL-5) plays an important role in proliferation and differentiation of human eosinophils. We report the isolation of cDNA clones from cDNA libraries of human eosinophils by using murine IL-5 receptor alpha chain cDNA as a probe. Analysis of the predicted amino acid sequence indicated that the human IL-5 receptor has approximately 70% amino acid sequence homology with the murine IL-5 receptor and retains features common to the cytokine receptor superfamily. One cDNA clone encodes a glycoprotein of 420 amino acids (Mr 47,670) with an NH2-terminal hydrophobic region (20 amino acids), a glycosylated extracellular domain (324 amino acids), a transmembrane domain (21 amino acids), and a cytoplasmic domain (55 amino acids). Another cDNA encodes only the extracellular domain of this receptor molecule. Other cDNA clones encode molecules having diversified cytoplasmic domains. COS7 cells transfected with the cDNA expressed a approximately 60-kD protein and bound IL-5 with a single class of affinity (Kd = 250-590 pM). The Kd values were similar to that observed in normal human eosinophils. In contrast to the murine 60-kD alpha chain, which binds IL-5 with low affinity (Kd = approximately 10 nM), the human alpha chain homologue can bind IL-5 with much higher affinity by itself. RNA blot analysis of human cells demonstrated two transcripts (approximately 5.3 and 1.4 kb). Both of them were expressed in normal human eosinophils and in erythroleukemic cell line TF-1, which responds to IL-5. The human IL-5 receptor characterized in this paper is essential for signal transduction, because expression of this molecule in murine IL-3-dependent cell line FDC-P1 allowed these cells to proliferate in response to IL-5.

Amino Acid Sequence↗
PubMed1992

Structure of the Bombyx mori fibroin light-chain-encoding gene: upstream sequence elements common to the light and heavy chain.

Two overlapping genomic clones containing the fibroin light-chain (Fib-L)-encoding gene (Fib-L) were obtained from the cosmid library of the silkworm, Bombyx mori J-139, by hybridization with the Fib-L cDNA clone. Sequencing of the 14.6-kb region revealed that Fib-L was 13,472 bp long containing seven exons, and that the gene contained a large first intron which occupied about 60% of the gene. Comparison of restriction patterns of the J-139 Fib-L with those of eight other B. mori breeds producing normal-level fibroin demonstrated that considerable restriction-fragment length polymorphisms were present in regions containing the first intron and the 3'-flanking sequence. However, sizes of the Fib-L mRNA and the Fib-L polypeptide were very similar among the nine breeds tested, suggesting that the exon sequences and the splice signals were all well conserved. 5'-Flanking regions of Fib-L and the fibroin heavy-chain (Fib-H)-encoding gene (Fib-H) compared in this study contained three 18-30-bp sequences of high similarity and many 8-10-bp common elements, six of which coincided with the binding sites of homeodomain proteins. Gel retardation assays with the nuclear extracts of the posterior and middle silk glands suggested that protein factors present in the posterior silk-gland nuclei could bind to a set of those common upstream elements.

Amino Acid Sequence↗