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Biomedical subjects

S Maeda

Publications and source records attributed to S Maeda.

At least 775 records · Page 43Linked to original sources
PubMed1988

[Effectiveness of FUT-175, protease inhibitor, as an anticoagulant to hemodialysis].

(6-Amidino-2-naphthyl 4-guanidino benzoate) dimethanesulfonate (FUT-175), a protease inhibitor, has been reported to be an effective anticoagulant during hemodialysis without heparin. The anticoagulant activity of FUT-175 is also reported to be short. We applied FUT-175 to 33 patients who were undergoing hemodialysis and susceptible to bleeding, to avoid the use of heparin. The concentration and anticoagulant activity of FUT-175 were relatively stable during hemodialysis. A 20-40 mg/h dose of FUT-175 prolonged coagulation time sufficiently in the instrumental blood of the extracorporeal circuit but not in the systemic blood. Its anticoagulant activity decreased immediately after hemodialysis. Therefore, we could manage all patients without any bleeding trouble during hemodialysis with FUT-175 as an anticoagulant. Although there were side effects of FUT-175, such as nausea, vomiting, itching and eruption, they were not serious, and FUT-175 could be administered without interruption. FUT-175 seems to be useful as an anticoagulant during hemodialysis for patients susceptible to bleeding.

Adult↗
PubMed1988

Veno-occlusive disease of the liver in a patient with allergic granulomatous angiitis.

A 45-yr-old woman, with asthma and skin erythema, was diagnosed as having allergic granulomatous angiitis. Leukocytosis accompanied by hypereosinophilia and characteristic histological findings of skin lesions also were present. Upon laparoscopy and liver biopsy, the liver showed a congestive appearance and, histologically, showed thickening of the central vein walls, as well as narrowing of the lumens with collagenous fibers, and pericentral hemorrhage with hepatocyte degeneration. A diagnosis of veno-occlusive disease of the liver was made. This is the first report on a case of veno-occlusive disease of the liver occurring in association with allergic granulomatous angiitis.

Female↗
PubMed1987

Lack of correlation between rare Ha-ras alleles and urothelial cancer in Japan.

Restriction fragment length polymorphism (RFLP) of Ha-ras gene was surveyed by Southern blot analysis in leukocyte DNA from 55 normal individuals and 58 urothelial cancer patients in Japan. Three common alleles and 4 rare alleles were classified. The frequency of common alleles in normal Japanese individuals differed from that in Caucasians previously reported; a 7.2-7.5-kb BamHI fragment of common allele was not observed in Japanese individuals. No significant increase in frequency of the rare Ha-ras allele was observed in the group of cancer patients. Moreover, no significant difference in frequency was observed for the 3 common alleles. Tumor DNA was compared with leukocyte DNA in 30 urothelial cancer patients: in 3 of 8 cases with heterozygous Ha-ras locus, decreased intensity of one band, indicating partial loss of one allele in tumor DNA, was observed. In 3 tumors with either deletion of one Ha-ras allele or a rare Ha-ras allele, expression of Ha-ras gene was examined by Northern blot analysis. Such genetic alterations did not always result in a marked increase in Ha-ras expression. These data suggest that these genetic alterations are not directly related to Ha-ras expression, and that RFLP of Ha-ras gene is not a useful genetic marker for urothelial cancer. On the other hand, deletion of one Ha-ras allele was observed in 1 of 5 cases of bladder cancer and in 2 of 3 cases of renal pelvic cancer, suggesting that that deletion may be important in the development of urothelial cancer.

Aged↗
PubMed1987

Establishment of a human urachal adenocarcinoma cell line (KO-BT-1) and its chemosensitivity.

A new human urachal adenocarcinoma cell line (KO-BT-1) was established and characterized. It consisted of cuboidal, spindle, and polymorphic giant cells and continued to grow for more than 27 months without contact inhibition. Doubling time was about 15.5 h at the 70th passage. In nude mice the cells produced tumors, the histologies of which were similar to the original patient-derived tumor. Moreover, serum carcinoembryonic antigen level was elevated in the patient and the histological section of tumor formed in nude mice was stained with an antibody to carcinoembryonic antigen by peroxidase-antiperoxidase method. Electron microscopically, the cells covered with microvilli had cell-junction complexes. The chromosome number was aneuploid with a modal number of 60. At clinically achievable concentrations, doxorubicin, cis-platinum, mitomycin C, and 40487S which was an in vitro-active type of cyclophosphamide did not reduce colony formation to 30% or less of the control value; likewise in this patient chemotherapy had not been effective. In addition, among human recombinant tumor necrosis factor, alpha-interferon, and recombinant beta- and gamma-interferon, recombinant IFN-beta was most effective against this tumor. These results indicated that KO-BT-1 cells showed the similar chemosensitivity and properties to those of the original tumor, and might be useful in basic studies for the diagnosis, treatment, and etiology of urachal tumors.

Adenocarcinoma↗
PubMed1987

Tissue-specific and developmental expression of human transthyretin gene in transgenic mice.

To analyze the regulation of transthyretin gene expression we have produced transgenic mice by microinjecting cloned human transthyretin genes into fertilized eggs of C57BL/6 mice. The 7.6-kilobase (kb) human transthyretin gene containing about 500 base pairs (bp) in the upstream region was used for microinjection. Seven out of nine transgenic mice had detectable amounts of human transthyretin in serum when analyzed by enzyme-linked immunosorbent assay. Transthyretin mRNA was detected in liver and yolk sac but not in other tissues including brain. The amount of mRNA was variable among transgenic mice and was about one-tenth of mouse endogenous transthyretin mRNA. Human and mouse transthyretin mRNAs were detected in liver of fetus and yolk sac at 13 days of gestation and unlike yolk sac the level of mRNA in liver increased gradually during development and reached the maximum at around 17 days of gestation. Human transthyretin was associated with mouse transthyretin to form tetramers as judged from the dilution curve of enzyme-linked immunosorbent assay and the spur formation in Ouchterlony assay.

Animals↗
PubMed1987

Prealbumin gene expression during mouse development studied by in situ hybridization.

Localization of prealbumin mRNA in tissues from mice at various stages of gestation was investigated using in situ hybridization procedures. Prealbumin mRNA was detected as early as the 10th day of gestation. It was specifically localized in endodermal cells of the visceral yolk sac, tela choroidea, and hepatocytes. In the adult mice, prealbumin mRNA was localized in the hepatocytes and choroid plexus epithelial cells. These observations indicate that synthesis of prealbumin mRNA is initiated in several different types of cells at early stages of fetal development.

Animals↗
PubMed1987

Molecular and cytogenetic studies on nucleolar cistrons (rDNA) in mouse leukemia cells.

The gene dosage change of nucleolar cistrons (rDNA) in tumor cells has not been extensively studied. The present studies showed that increased dosage, as well as abnormal distribution of rDNA, was frequently associated with leukemia cells of SL/Ni and AKR mice. In normal SL cells, 37%, 39%, and 25% of rDNA was located in nucleolar organizer regions (NOR) of chromosomes #12, #18, and #19, respectively. Increase of rDNA/DNA was shown by hybridization on filter membranes in SL1, SL2, SL3, and M1 leukemia cells. Direct measurement of rDNA/DNA in G1 cells revealed an 11% increase in synchronized M1 cells. The increased rDNA dosage was explained by trisomy 12 in SL1 and SL2, the ectopic NOR of #9 in SL3, and the double t(X;19) marker chromosomes in M1. On the other hand, in normal AKR cells, 27%, 29%, and 45% of rDNA was assigned to NORs of chromosomes #15, #16, and #18, respectively. The relative rDNA distribution among NORs estimated by autoradiographic grain counting was suggested to be abnormal in AKR leukemia cells despite their normal karyotype; 36% rDNA was shown to be in chromosomes #15 and #16, respectively, by relative reduction in chromosome #18 in AKR1; the trisomy 15 explained the increased rDNA in AKR2; a relative increase was found in chromosome #15 in AKR3. These results were discussed with reference to the reported NOR involvement in chromosome translocation and amplification in tumor cells.

Animals↗
PubMed1987

Chromosome marker and enhanced expression of c-Ha-ras in a DMBA-induced erythroleukemia cell line (D5A1).

Oncogene activation induced by chromosomal changes is now regarded as one of the most important phenomena during carcinogenesis. We have reported c-abl activation in a rat leukemia cell line K3D, caused by a secondary chromosomal translocation. Another erythroblastic leukemia cell line D5A1, originally derived from a leukemia induced by 7,12-dimethylbenz(a)anthracene (DMBA) in a Long-Evans rat, is characterized by a marker chromosome 1q+, which also probably occurred as a secondary change. In this cell line, the transcription level of Ha-ras related mRNA increased compared with other cell lines. By the in situ hybridization technique, the c-Ha-ras locus was assigned to 1q43 and the breakpoint 1q+. Because the breakpoint was so near the c-Ha-ras locus on the chromosome, the present system may provide a model of activation of the c-Ha-ras gene brought about by chromosomal translocation.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1987

Use of the silkworm, Bombyx mori, and an insect baculovirus vector for high-level expression and secretion of biologically active mouse interleukin-3.

Using the virus vector derived from a baculovirus of Bombyx mori (Bm), we constructed an infectious recombinant virus carrying the mouse interleukin-3 (IL-3) cDNA placed downstream from the polyhedrin promoter. Silkworms infected in vivo with recombinant virus or the silkworm-derived BmN cell line infected in vitro secreted large amounts of IL-3 into hemolymph or culture medium, respectively. On a per volume basis, about 20-fold more activity was found in the culture supernatants of the infected BmN cells and 10000-fold more activity was detected in the hemolymph as compared to supernatants obtained from COS7 monkey cells transfected with plasmid pcD-IL3 using the SV40 early promoter [Yokota et al., Proc. Natl. Acad. Sci. USA 81 (1984) 1070-1074]. Three distinct species of Il-3 of molecular masses, 18, 20 and 22 kDa were produced and all were converted to a 15-kDa protein by N-glycanase digestion, indicating that silkworm cells glycosylated IL-3. The N-terminal amino acid sequences of the IL-3 purified from tissue culture medium and hemolymph were identical to that of mammalian-derived IL-3, showing that silkworm cells recognized the mammalian signal sequence and cleaved it at the correct position. The purified silkworm-produced IL-3 had biological activities indistinguishable from IL-3 produced by mammalian cells as assessed by mast-cell proliferation assays, colony-formation assays using mouse bone marrow cells, and by receptor-binding assays using [125I]IL-3.

Animals↗
PubMed1987

Enhanced inhibition of anticancer drugs by human recombinant gamma-interferon for human renal cell carcinoma in vitro.

We studied the inhibitory effect of seven anticancer drugs and alpha-, recombinant beta-, and recombinant gamma-interferons on the in vitro growth of two established human renal cell carcinomas and 16 renal cell carcinomas obtained from patients using monolayer culture and the double-layer soft agar system. Recombinant gamma-interferon was the most effective of three types of interferon. Combined treatment with recombinant gamma-interferon and some anticancer drugs inhibited the cell growth in both cell lines more than treatment with each drug alone. Treatment with recombinant gamma-interferon and cisplatinum or 5-fluorouracil following a 24-hour incubation with the interferon was more effective than when interferon and the drug were given simultaneously. Treatment using doxorubicin, cisplatinum, or vinblastine with recombinant gamma-interferon synergistically inhibited colony formation in 11 of the 16 renal cell carcinomas that showed clonal growth. Our results suggest that treatment with anticancer drugs in combination with recombinant gamma-interferon is effective for renal cell carcinoma.

Antineoplastic Agents↗
PubMed1987

Cannabinoids induce incomplete maturation of cultured human leukemia cells.

Monocyte maturation markers were induced in cultured human myeloblastic ML-2 leukemia cells after treatment for 1-6 days with 0.03-30 microM delta 9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana. After a 2-day or longer treatment, 2- to 5-fold increases were found in the percentages of cells exhibiting reactivity with either the murine OKM1 monoclonal antibody or the Leu-M5 monoclonal antibody, staining positively for nonspecific esterase activity, and displaying a promonocyte morphology. The increases in these differentiation markers after treatment with 0.03-1 microM THC were dose dependent. At this dose range, THC did not cause an inhibition of cell growth. The THC-induced cell maturation was also characterized by specific changes in the patterns of newly synthesized proteins. Pronounced among these changes was an increase in the synthesis of at least 10 proteins that are found abundantly in monocytes. The THC-induced differentiation did not, however, result in cells with a highly developed mature monocyte phenotype; the THC-treated cells failed to exhibit other monocyte markers such as attachment to the surface of tissue culture dishes or morphological maturation beyond the promonocyte stage. However, treatment of these "incompletely" matured cells with either phorbol 12-myristate 13-acetate or 1 alpha,25-dihydroxycholecalciferol, which are inducers of differentiation in myeloid leukemia cells (including ML-2 cells), produced cells with a mature monocyte morphology. Two other cannabinoids, cannabidiol and cannabinol, which were more cytotoxic than THC at comparable doses, also caused an increase in the expression of maturation markers, but at doses higher than those required for THC. The ML-2 cell system described here may be a useful tool for deciphering critical biochemical events that lead to the cannabinoid-induced "incomplete" cell differentiation of ML-2 cells and other related cell types. Findings obtained from this system may have important implications for studies of cannabinoid effects on normal human bone-marrow progenitor cells.

Calcitriol↗
PubMed1987

Expression of a pseudogene for interferon-alpha L.

The human leukocyte interferon-alpha L (IFN-alpha L) appears to be a pseudogene because it contains a termination codon in the DNA coding for the precursor peptide (signal peptide), but the remainder of the gene codes for an interferon protein of normal length. To determine if this gene codes for an active interferon molecule, an expression plasmid was constructed for IFN-alpha L that was produced in Escherichia coli. The IFN-alpha L is active on human and bovine cells, and exhibits a trace of activity on mouse cells.

Cloning, Molecular↗
PubMed1987

Hyperproduction of polyhedrin-IGF II fusion protein in silkworm larvae infected with recombinant Bombyx mori nuclear polyhedrosis virus.

A gene coding for insulin-like growth factor II (IGF II) was constructed from 16 oligodeoxynucleotides synthesized chemically and cloned into EcoRI-SalI sites of pBR322. In this gene at ATG codon for methionine was introduced for cleavage by CNBr at the beginning of mature IGF II. For expressing foreign genes, a new host-vector system, with Bombyx mori silkworm larvae as the host and B. mori nuclear polyhedrosis virus (BmNPV) as the vector, has been developed. BmNPV genomic DNA codes polyhedrin which is a major protein of inclusion bodies and is mass-produced in infected silkworm larvae. We employed this polyhedrin production system to obtain a large yield of a foreign gene product. The coding region of the carboxy-terminal half of polyhedrin was removed and the remainder was ligated with the IGF II gene in phase to create a fusion protein gene consisting of the coding region of the amino-terminal half of polyhedrin and the IGF II gene. This fusion protein gene was combined in a plasmid with the promoter and 5' and 3' flanking regions of the polyhedrin gene. The resulting plasmid and the wild-type BmNPV genomic DNA were cotransfected into BM-N cells, and a recombinant virus was isolated by the limiting dilution method. The silkworm larvae infected with the recombinant virus produced 3.6 mg of the fusion protein per larva and the infected BM-N cells produced 0.3 mg per ml of culture. IGF II was released from the fusion protein produced by BM-N cells infected with the recombinant virus by CNBr treatment, purified by extraction with guanidine-HCl, column chromatography and HPLC and the correct amino-terminal amino acid sequence confirmed.

Animals↗