Biomedical subjects

M Terada

Publications and source records attributed to M Terada.

At least 253 records · Page 14Linked to original sources

PubMed1995

Rapid isolation of cell-type-specific protein tyrosine kinases by degenerate polymerase chain reaction combined with differential hybridization technique.

To identify protein tyrosine kinase (PTK) genes preferentially expressed in renal cell carcinoma cell line, we screened a PTK-cDNA-enriched library constructed from RNA of an renal cell carcinoma cell line with a PTK probe, each produced from renal cell carcinoma, gastric cancer or esophageal cancer cell lines by degenerate polymerase chain reaction. Two cDNA fragments of PTK genes, FRK and FLT-3, were isolated from the PTK-cDNA-enriched library of the renal cell carcinoma cell line by differential hybridization technique. The FRK cDNA clone represented 15.8% of the PTK-cDNA-enriched library from the renal cell carcinoma cell line, while the FLT-3 cDNA clone was 2.8% of the same library. Both of the two PTK genes were expressed preferentially in renal cell carcinoma cell lines. This method, described here, is useful for the rapid isolation of PTK cDNA fragments, including a low abundant cDNA, preferentially expressed in a specific cell line.

Base Sequence↗

PubMed1995

Liposome-mediated in vivo gene transfer of antisense K-ras construct inhibits pancreatic tumor dissemination in the murine peritoneal cavity.

K-ras point mutation occurs at a characteristically high incidence in human pancreatic cancer. Plasmids expressing antisense (AS), AS-K-ras-LNSX or sense K-ras gene fragment, were first transduced into three human pancreatic cancer cell lines (AsPC-1, MIAPaCa-2, and BxPC-3) by liposome-mediated transfection. A stable expression of antisense or sense K-ras RNA was detected by Northern blot analysis, and Western blot analysis confirmed a reduction of up to 20% of K-ras-specific p21 protein in AsPC-1 cells transduced with AS-K-ras-LNSX. The growth of pancreatic cancer cells with K-ras point mutations (AsPC-1 and MIAPaCa-2) was significantly suppressed after transduction of AS-K-ras-LNSX, although the effect of antisense construct was not found in cells with a wild-type K-ras gene (BxPC-3). Next, to test the efficacy in vivo, AsPC-1 cells were inoculated into the intraperitoneal cavity of nude mice, and 3 days later, the AS-K-ras-LNSX:liposome complex was injected i.p. 3 times. Twenty-eight days after tumor cell inoculation, 9 of 10 control mice developed peritoneal dissemination and/or solid tumors on the pancreas, whereas only 2 of 12 mice treated with AS-K-ras-LNSX showed any evidence of tumors. Although PCR analysis indicated that the injected DNA was delivered to various organs except for the brain, treatment-related toxicity was not observed. This study shows that the liposome-mediated in vivo gene transfer of antisense K-ras construct may be a useful therapeutic strategy for pancreatic cancer.

Animals↗

PubMed1995

Mutation frequency of the p16/CDKN2 gene in primary cancers in the upper digestive tract.

We report a highly frequent homozygous deletion of the p16/CDKN2 gene in the esophageal cancer cell line and a relatively high frequency of homozygous deletion in gastric cancer cell lines. In contrast, in primary esophageal carcinomas, mutation frequency of the p16/CDKN2 gene has been controversial (0, 21, and 52% previously reported), and no reports are available for the mutation frequency of this gene in surgical specimens of gastric carcinomas. Here we report that four (16%) of 25 primary esophageal squamous cell carcinomas were found to be mutated, one in exon 1 and three in exon 2, and that no mutations were observed in 19 surgical specimens of gastric adenocarcinomas. This is the first report showing the absence or quite low frequency of mutation in surgical specimens of gastric carcinomas.

Base Sequence↗

PubMed1995

Cloning and characterization of MST, a novel (putative) serine/threonine kinase with SH3 domain.

Protein kinases play a key role in cell growth regulation. We have isolated a cDNA fragment of the MST gene from the MKN28 gastric cancer cell line cDNA pool by degenerate polymerase chain reaction. MST-cDNAs were cloned from the human brain cDNA library. Nucleotide sequence analysis indicated that the MST gene encodes a novel putative non-receptor type of serine/threonine kinase with Src homology 3 (SH3) domain, two leucine zipper domains and proline rich domain. The deduced amino acid sequence corresponding to a part of kinase domain and leucine zipper domains of MST (amino acid codons 244-461) is almost identical to the published partial amino acid sequence of MLK2. MST is the first non-receptor type of serine/threonine kinase containing SH3 domain, leucine zipper domain and proline rich domain other than PTK1/Sprk. The MST gene was moderately expressed in brain, skeletal muscle and testis as a 3.8 kb mRNA, and the MST gene has been mapped to human chromosome 19q13.1-q13.2.

Amino Acid Sequence↗

PubMed1995

Influence of high glucose on 1,25-dihydroxyvitamin D3-induced effect on human osteoblast-like MG-63 cells.

Impaired bone formation due to defective osteoblast function, as reflected in a decreased serum osteocalcin (OC) concentration in the patients with diabetes, has been implicated in the development of diabetic osteopenia. The role of hyperglycemia in this decrease in serum OC concentration was investigated. 1,25-dihydroxyvitamin D3 (1,25[OH]2D3), an active form of vitamin D3, stimulated OC secretion from the human osteosarcoma cell line MG-63 in a dose-dependent manner. Exposure of the cells to high concentrations of glucose for 7 days significantly impaired 1,25(OH)2D3-induced OC secretion as compared with that observed with cells maintained under normal glucose (5.5 mM) or high mannitol conditions. The inhibitory effect of glucose was in a dose-dependent manner up to 55 mM. High glucose (55 mM) also attenuated the 1,25(OH)2D3-induced increase in OC mRNA abundance in MG-63 cells, suggesting that the inhibition of the 1,25(OH)2D3-induced increase in OC secretion by exposure to a high concentration of glucose was, at least in part, mediated at the transcriptional level. High glucose significantly decreased the number of 1,25(OH)2D3 receptors in MG-63 cells, without any change in the dissociation constant for 1,25(OH)2D3; this effect was not mimicked by high mannitol, indicating specificity for glucose. These observations suggest that a high glucose concentration significantly impairs the ability of osteoblastic cells to synthesize OC in response to 1,25(OH)2D3 by reducing 1,25(OH)2D3 receptor number, and that impaired cell function caused by sustained exposure to high glucose contributes to the defect in bone formation observed in the patients with diabetic osteopenia.

Amino Acid Sequence↗

PubMed1995

Effects of PF1022A on adult Angiostrongylus cantonensis in the pulmonary arteries and larvae migrating into the central nervous system of rats.

We examined the effects of PF1022A, newly developing in Japan, on adult Angiostrongylus cantonensis in the pulmonary arteries of rats. Following five and ten successive oral doses at 10 mg/kg per day, the first-stage larvae in rat faeces disappeared completely at 2 weeks after treatment. The treatment completely killed the female worms, but not the male worms. However, numbers of male worms were also decreased after the administration of either five successive oral doses at 10 mg/kg per day for four courses or five successive intraperitoneal doses at 0.5 mg/kg per day. Next, we examined the effects of PF1022A on larval A. cantonensis migrating into the central nervous system (CNS) of rats. Following five successive oral doses at 5 or 10 mg/kg per day and five successive intraperitoneal doses at 0.5 mg/kg per day, lesser killing effects were observed on male as well as female worms. On the basis of these results it is apparent that PF1022A will become a promising anthelmintic available as treatment for tissue-dwelling as well as intestinal nematodes.

Administration, Oral↗

PubMed1995

In vitro effects of VD-99-11 on Angiostrongylus cantonensis and isolated frog rectus.

In vitro effects of VD-99-11 were examined using adult Angiostrongylus cantonensis and isolated frog rectus. In A. cantonensis, paralysis was elicited by VD-99-11 at 10(-9)-10(-6) g/ml. The paralysis caused by VD-99-11 (10(-8) g/ml) was antagonized by picrotoxin or bicuculline but not by phentolamine. A relationship between VD-99-11 and gabergic antagonists was observed in worm preparations contracted by eserine or pyrantel: VD-99-11 at higher concentrations (3x10(-6) g/ml) caused a marked contraction. In worm preparations contracted with eserine or pyrantel, the only additional contraction induced by VD-99-11 (5x10(-6) g/ml) was antagonized by strychnine. In experiments on the guanidine (2.5x10(-3) M)-induced twitch responses in isolated frog rectus, marked stimulation was caused by VD-99-11 (3-5x10(-6) g/ml). The stimulated responses induced by VD-99-11 were antagonized by tetrodotoxin, D-tubocurarine, strychnine, and hemicholinium-3, respectively. These results suggest that VD-99-11 seems superior to milbemycin D, milbemycin oxime, and ivermectin in some aspects, such as in vitro potency, though this new substance is similar to these drugs in having two different actions on the gabergic mechanism at lower concentrations and on the cholinergic mechanism at higher concentrations.

Angiostrongylus cantonensis↗

PubMed1995

Amplification and detection of the VNTR locus D4S95 in a Japanese population.

The D4S95-VNTR locus was amplified and the polymorphism analysed in a population sample of 169 randomly selected Japanese individuals. A total of 14 alleles containing 850-1360 base pairs were distinguished by agarose gel electrophoresis. The distribution of alleles was symmetrical with respect to one peak at 1030 bp. The mean exclusion chance and discrimination power were calculated as 0.604 and 0.876 respectively.

Alleles↗

PubMed1995

Successful left trisegmentectomy for ruptured hepatoblastoma using intraoperative transarterial embolization.

Although surgical treatment with resection for spontaneous rupture of hepatoblastoma into the free abdominal cavity is difficult in small children, it may be the only treatment available. The authors describe a 16-month-old girl who showed a progressive decrease in hematocrit and no response to blood transfusion, after spontaneous rupture of a large hepatoblastoma that extended to the pubic bone. Percutaneous transcatheter arterial embolization could not be performed because selective catheterization was impossible. Therefore, emergency surgery was conducted. After intraoperative transcatheter arterial embolization (IOTAE) to control hemorrhage, left trisegmentectomy was performed. The patient then underwent chemotherapy, followed by autologous bone marrow transplantation. The hemorrhage from the ruptured tumor was completely arrested by IOTAE, and the postoperative course was uneventful. Hepatic resection after IOTAE, followed by chemotherapy and bone marrow transplantation, represents a promising treatment for ruptured hepatoblastoma.

Angiography↗

PubMed1995

Characterization of the gubernacular contractile response to calcitonin gene-related peptide in the mouse.

Calcitonin gene-related peptide (CGRP) has no effect on quiescent skeletal muscle, but cultured neonatal mice gubernacula show rhythmic contractions in response to CGRP. This study investigated whether these contractions (1) require calcium ions, (2) are activated via acetylcholine receptors, or (3) require dihydropyridine receptors. Gubernacula (n = 20 for each experiment) from male mice aged 7 days old were preincubated for 30 minutes in aerated culture medium (Krebs-Henseleit solution) with (1) up to 1.8 mmol/L of calcium with or without CGRP (714 nmol/L), (2) up to 5.0 mumol/L of curare with CGRP and calcium (1.8 mmol/L), or (3) up to 1 mumol/L of nifedipine with CGRP and calcium. Then they were placed on agar-coated grids over the same compound solutions, and observed for 2 days by video camera to see contractions. Of gubernacula cultured with calcium (1.8 mmol/L) and CGRP, 90% showed contractions, which decreased to 20% without CGRP (P < .001) and 15% without calcium (P < .001). Only 5% of gubernacula cultured without both CGRP and calcium showed contractions. Also these contractions in response to CGRP depended on calcium concentrations in a dose-dependent manner. Curare did not suppress contractions. With increasing dose of nifedipine, the percentage of gubernacula contracting decreased from 95% to 0%. These results suggest that developing mouse gubernacular contractions in response to CGRP require influx of calcium ions to the sarcoplasm via dihydropyridine receptors in a similar manner to contractions of immature cardiac or smooth muscles, and these contractions are not activated via acetylcholine receptors.

Animals↗

PubMed1995

Gene transfer and expression in progeny after intravenous DNA injection into pregnant mice.

Several methods that enable foreign genes to be transferred directly into germ cells and adult animals have been developed, which have stimulated great interest in manipulating genes in vivo. However, there have been no methods available for introducing genes into fetuses. We report here that a single intravenous injection of expression plasmid: lipopolyamine complexes into pregnant mice resulted in successful gene transfer into the embryos. The transgenes thus introduced were expressed in the fetuses and newborn progeny. This simple and new method of gene transfer into embryos will facilitate rapid analysis of transgene effects in the fetuses and will be useful for studying gene-deficient animal models to gain transgene functions at desired stages of embryogenesis.

Animals↗

PubMed1995

Hst-1 (FGF-4) antisense oligonucleotides block murine limb development.

The initiation of limb development depends on the site specific proliferation of the mesenchyme by the signals from the apical ectodermal ridge (AER) in embryonic mouse. We have previously reported that the local expression of Hst-1/Fgf-4 transcripts in AER of the mouse limb bud is developmentally regulated, expressed at 11 and 12 days post coitus (p.c.) embryo. In an effort to further understand the role of Hst-1/FGF-4 in mouse limb development, an antisense oligodeoxynucleotides (ODNs) study was performed. We first established a novel organ culture system to study mouse limb development in vitro. This system allows mouse limb bud at 9.5-10-d p.c. embryo, when placed on a sheet of extracellular matrix in a defined medium, to differentiate into a limb at 12.5-d p.c. embryo within 4.5 d. Using this organ culture system, we have shown that exposure of 9.5-10-d p.c. embryonal limb bud explants to antisense ODNs of Hst-1/FGF-4 blocks limb development. In contrast, sense and scrambled ODNs have no inhibitory effect on limb outgrowth, suggesting that Hst-1/FGF-4 may work as a potent inducing factor for mouse limb development.

Animals↗

PubMed1995

Identification of a novel phospholipase C family gene at chromosome 2q33 that is homozygously deleted in human small cell lung carcinoma.

Since a considerably high incidence of allelic loss on chromosome 2q was detected in lung carcinoma and a homozygous deletion at chromosome 2q33 was detected in a small cell lung carcinoma cell line, NCI-H82, a novel tumor suppressor gene has been suggested to be present in this chromosomal region. In the present study, we constructed a cosmid contig map covering the homozygous deleted region, which was estimated as being 220 kbp in size, and identified a gene from the deleted region. All of the coding exons of this gene were homozygously deleted in this cell line, while a 5'-non-coding exons was retained. Since the gene encodes a protein with striking similarity to several members of a family of phospholipase C, we designated this gene as PLC-L (phospholipase C-deleted in lung carcinoma). The PLC-L gene was expressed in a variety of fetal and adult organs including the lung. However, its expression was greatly reduced in seven of 13 (53.8%) of small cell lung carcinoma and 13 of 15 (86.7%) of non-small cell lung carcinoma cell lines. Since its homology to phospholipase C genes suggests the involvement of the PLC-L gene in inositol phospholipid-based intracellular signaling cascade, it is possible that aberrant expression of the PLC-L gene contributes to the genesis or progression of human lung carcinoma.

Amino Acid Sequence↗

PubMed1995

The role of the genitofemoral nerve and calcitonin gene-related peptide in congenitally cryptorchid mutant TS rats.

We investigated whether previous gubernacular denervation in TS rats changes the gubernacular contractile response to or binding capacity of calcitonin gene-related peptide receptors. In TS rats there is excessive calcitonin gene-related peptide in the genitofemoral nerve and 85% of the male rats have cryptorchidism. TS rats and controls underwent genitofemoral nerve transection or sham operation at day 0. On day 3 gubernacula were cultured with or without calcitonin gene-related peptide to observe contractions. Gubernacular frozen sections were incubated with 125iodine calcitonin gene-related peptide with or without unlabeled calcitonin gene-related peptide. Exposed x-ray films were quantified by computerized densitometry. In the sham operated controls contractility increased from 15 to 55% by adding calcitonin gene-related peptide compared with 5% and 10%, respectively, in the TS rats. After genitofemoral nerve denervation exogenous calcitonin gene-related peptide increased contractility to 90% in controls and 75% in TS rats. Previous genitofemoral nerve transection increased specific 125iodine calcitonin gene-related peptide binding 21% in controls and about 100% in TS rats. Genitofemoral nerve transection in TS rats restored gubernacular contractile response to calcitonin gene-related peptide in vitro and doubled the binding capacity of calcitonin gene-related peptide receptors.

Animals↗

PubMed1995

Serum antibody against unfused recombinant E7 protein of human papillomavirus type 16 in cervical cancer patients.

Sera were examined for the presence of antibody against E7 protein of human papillomavirus type 16 (HPV-16) by Western blot analysis using the bacterially derived unfused protein. The occurrence rates of anti-E7 antibody against HPV-16 were 14.1% (10/71) in cervical cancer patients, 0% (0/48) in cervical intraepithelial neoplasia patients, and 0% (0/41) in female non-malignant patients. Three patients (one with endometrial cancer, one with breast cancer, and one male patient with colon polyp) out of 115 patients with tumors in organs other than the cervix, had antibody against E7 protein of HPV-16. The serum antibody, once positive, could be detected for a long time after surgical removal of the cancers in all cases that could be followed up. HPV-16 DNA could be detected in 50% (13/26) of cervical cancer patients. Sixty-nine percent (9/13) of patients with HPV-16 DNA in cancers had the antibody and all the patients with stages II, III, and IV cervical cancer (8/8) harboring HPV-16 DNA showed the presence of the antibody against E7 protein of HPV-16. In contrast, only 20% (1/5) of cervical cancer patients with stage Ia or Ib harboring HPV-16 DNA showed positive for the anti-E7 antibody in sera. These findings suggest that the presence of anti-E7 antibody in serum depends on the staging of cervical cancer and extent of HPV infection.

Adult↗

PubMed1995

Frequent development of murine T-cell lymphomas with TcR alpha/beta+, CD4-/8- phenotype after implantation of human inflammatory breast cancer cells in BALB/c nude mice.

Tumors developed quite frequently in some of the visceral organs, including spleen and liver, in BALB/c nude mice upon subcutaneously xenografting surgical specimens from five different inflammatory breast cancer patients. All of these tumors developed within two and a half months to one year after the subcutaneous inoculation of surgical specimens. From these tumors, five independent transplantable tumors, including tMK-2, tHK-1, tYK-1, tYK-2 and tTY-1 have been established. Chromosome analysis, morphologic studies by light and electron microscopy and phenotype analysis indicated that these tumors are of mouse origin. The tMK-2 tumor was highly metastatic to the spleen and liver when it was subcutaneously transplanted into the right scapular region. In addition, the region where the tMK-2 tumor cells were subcutaneously inoculated showed an apparently inflammatory process represented by erythema. After subcutaneous inoculation into the right scapular region, tHK-1, tYK-1, 2, and tTY-1 tumors also metastasized to some of the visceral organs, including spleen and liver. From these tumors, in vitro cell lines were established. The cells grew in a stromal-cell dependent manner under in vitro culture conditions. The cells were again tumorigenic at the inoculated region and metastasized to various organs, including liver and spleen, of BABL/c nude mice. Histological examination revealed that the tumors showed features of malignant lymphoma. Phenotypically, these five tumors expressed early T lymphocyte markers as revealed by anti-mouse anti-TcR alpha/beta, anti-CD3, CD4 and CD8 monoclonal antibodies. To our knowledge, these cell lines are the first T-cell lines showing the phenotype of extrathymically differentiated T-cells in the liver.

Animals↗

PubMed1995

Basic fibroblast growth factor as a candidate tumor marker for renal cell carcinoma.

The present investigation was conducted to determine serum levels of basic fibroblast growth factor (FGF) by enzyme immunoassay in patients with various urogenital tumors. Renal cell carcinoma had a higher tendency (28 of 52, 53.8%) toward increased serum levels of basic FGF than any of the other urogenital tumors, and increased serum basic FGF was detected more frequently in patients with advanced renal cell carcinoma. Analysis of histological pattern indicated that renal cell carcinoma with a solid or tubular component is more likely to produce basic FGF. However, no significant difference was seen between the percentage of clear cell type tumor patients with increased serum basic FGF (50.0%) and the percentage of granular cell type tumor patients with increased serum basic FGF (66.7%). Five of 8 patients with renal cell carcinoma who underwent selective renal venous sampling before nephrectomy showed increased serum basic FGF in the renal vein from the affected kidney. After resection of the affected kidney to remove the cancer, serum basic FGF disappeared within 2 weeks. However, residual huge tumor or postoperative disease prolonged the increased levels of basic FGF in 2 patients, indicating that basic FGF is produced from and secreted by tumor tissue itself. These findings suggest that serum basic FGF can be useful in the diagnosis, and in evaluating the prognosis, of patients with renal cell carcinoma.

Biomarkers, Tumor↗

PubMed1995

Presence of Streptococcus DNA sequence in surgical specimens of gastric cancer.

In Southern blot analysis using Mycoplasma 16S ribosomal DNA (rDNA) as a probe, positive signals were detected in DNA samples from surgical specimens of gastric cancers. The DNA that hybridized to Mycoplasma 16S rDNA was eluted from the gel, cloned and sequenced. The cloned sequence was identical to 16S rDNA of Streptococcus anginosus. In Southern blot analysis with the S. anginosus 16S rDNA fragment as a new probe, positive signals were detected in 9 (20%) out of 43 cases of gastric cancer.

Adenocarcinoma↗