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Biomedical subjects

N Murai

Publications and source records attributed to N Murai.

At least 91 records · Page 5Linked to original sources

Hygromycin resistance gene cassettes for vector construction and selection of transformed rice protoplasts.

Hygromycin resistance gene cassettes were designed to facilitate vector construction for plant transformation. Unique EcoRI, Pstl, and Sacll sites in the coding sequence of a hygromycin B phosphotransferase gene (hph) from Escherichia coli were eliminated. The mutated hph genes were used to form gene cassettes flanked by EcoRI-Sacll-Kpnl-Hindlll sites. Hygromycin resistance of wild-type and mutated hph genes was indistinguishable in E. coli and rice protoplast growth assay.

Journal Article↗

Molecular Basis of Imidazolinone Herbicide Resistance in Arabidopsis thaliana var Columbia.

Acetolactate synthase (ALS), the first enzyme in the biosynthetic pathway of leucine, isoleucine, and valine, is inhibited by imidazolinone herbicides. To understand the molecular basis of imidazolinone resistance, we isolated the ALS gene from an imazapyr-resistant mutant GH90 of Arabidopsis thaliana. DNA sequence analysis of the mutant ALS gene demonstrated a single-point mutation from G to A at nucleotide 1958 of the ALS-coding sequence. This would result in Ser to Asn substitution at residue 653 near the carboxyl terminal of the matured ALS. The mutant ALS gene was introduced into tobacco using Agrobacterium-mediated transformation. Imidazolinone-resistant growth of transformed calli and leaves of transgenic plants was 100-fold greater than that of nontransformed control plants. The relative levels of imidazolinone-resistant ALS activity correlated with the amount of herbicide-resistant growth in the leaves of transgenic plants. Southern hybridization analysis confirmed the existence of transferred ALS gene in the transformant showing high imazapyr resistance. The results demonstrate that the mutant ALS gene confers resistance to imidazolinone herbicides. This is the first report, to our knowledge, of the molecular basis of imidazolinone resistance in plants.

Journal Article↗

[Rupture of hepatocellular carcinoma with multiple pulmonary metastasis successfully treated by transcatheter arterial embolization (TAE) of tumor: a case report].

A 66-year-old woman was hospitalized in a state of shock with rupture of hepatocellular carcinoma and multiple pulmonary metastasis. Her bleeding was successfully controlled by emergency transcatheter arterial embolization with Lipiodol (Lp-TAE). Treatments with UFT, OK-432 and two additional Lp-TAE caused the disappearance of pulmonary metastasis with AFP levels decreased and natural killer cell activity increased. The patient died one and a half years after the emergency Lp-TAE. The disappearance of pulmonary metastatic lesions seemed to be caused by improvement of the patient's immunity, which related to the regression of primary tumor after Lp-TAE. It was suggested that Lp-TAE is worth undertaking even in rupture of hepatocellular carcinoma with remote metastatic lesions.

Aged↗

Gallium-67 uptake in fibrous dysplasia of the bone.

In a 43-year-old woman with fibrous dysplasia of the ribs and facial bone and in a 40-year-old man with fibrous dysplasia of the facial bone, there were considerable increases in the uptake of Tc-99m methylenediphosphonate (Tc-99m MDP) and Gallium-67 citrate. Fibrous dysplasia should be added to differential diagnosis of high Gallium-67 citrate uptake in the bone lesions.

Adult↗

A polyethylene glycol-mediated protoplast transformation system for production of fertile transgenic rice plants.

We have established an efficient procedure for protoplast transformation and regeneration of fertile transgenic plants of rice (Oryza sativa L.) cultivars Nipponbare and Taipei 309. Protoplasts were mixed with a plant-expressible hygromycin resistance gene and treated with 25% (w/v) polyethylene glycol. Stringent selection of transformed colonies was applied to 14-day-old regenerated protoplasts in the presence of 95 micromolar of hygromycin B for 12 days. After selection, 450 and 200 resistant colonies were recovered per million treated Taipei 309 and Nipponbare protoplasts, respectively. Southern hybridization analysis of hygromycin-resistant cell lines and regenerated plants indicated that 1 to 10 copies of transferred DNA were integrated at 1 to 4 loci of the rice genome. Southern DNA analysis suggests that the introduced plasmid DNA may form concatemers by intermolecular recombination prior to integration. Four Taipei 309 and 39 Nipponbare transgenic rice plants were regenerated and grown to maturity in the greenhouse. Two Taipei 309 and 35 Nipponbare plants set viable seeds. Agronomic traits of Taipei 309 transgenic plants and inheritance of the hygromycin resistance trait by progeny of the selfed transgenic plants were analyzed.

Journal Article↗

[Radiotherapy combined with cis-diammine-dichloro platinum (II) plus vindesine in the treatment of non-small cell lung cancer: a comparison with treatment by radiation alone].

The effect of CDDP + VDS has been evaluated in 39 cases of non-small cell lung cancer, compared with those treated with radiation alone. Nineteen cases consisted of a combined radiation and chemotherapy group, while twenty cases were classed a the radiation therapy only group. CDDP was given at a dosage of 60 to 110 mg/m2 every 4 weeks, and VDS at a dosage of 3 mg/m2 3 times weekly. Radiation was given at a fraction dose of 1.5 to 2 Gy 5 times per week with a mean total dose of 56 Gy in the radiation only group, and 50 Gy in the combined therapy group. There were no significant difference in both the response rate and the survival time between the two groups. This suggests that combined chemotherapy was not effective for the treatment of non-small cell lung cancer.

Aged↗

Acute aortic dissection due to giant cell arteritis. Report of two autopsy cases.

Two autopsy cases of giant cell arteritis with aortic dissection are reported. One patient was an 87-year-old man, and the other was an 80-year-old woman. In both cases the patient died suddenly, and fatal pericardial bleeding due to the aortic dissection was revealed at autopsy. Histologically, marked inflammation with giant cells was observed in the wall of the aorta and in other arteries including the cranial arteries. The authors therefore consider that giant cell arteritis was one of the preceding lesions that culminated in aortic dissection.

Aged↗

[Radiotherapy in bone metastases--with special reference to its effect on relieving pain].

Between December 1986 and January 1978, 68 patients with bone metastases were analyzed to evaluate the effect of radiation for the relief of pain. The 68 patients, who had a total of 97 lesions, complained of pain caused by their bone metastasis. The good, fair, and poor responses were found to be 18%, 60%, and 22%, respectively. With reference to the primary neoplasms, the effective response rate was 73% in lung cancer, 100% in breast cancer, 75% in gastric cancer, 100% in hepatic cancer, 100% in bladder cancer, 25% in epipharyngeal cancer, and 70% in the other neoplasms. Depending on the cell types of the lung cancer, the effective response rate was 80% for small cell carcinomas, 72% for adenocarcinomas and 40% for squamous cell carcinomas. Our results suggest that radiotherapy for bone metastases is to be recommended, since the effective response rate was 78% for the relief of pain.

Adenocarcinoma↗

Endogenous cytokinins in the ribosomal RNA of higher plants.

Endogenous cytokinin-active ribonucleosides were isolated from the rRNA and tRNA of pea epicotyls (Pisum sativum L., var Alaska) and of wheat germ (Triticum aestivum). The RNA preparations were analyzed for cytokinins by enzymic hydrolysis, ethyl acetate extraction, and Sephadex LH-20 fractionation in several solvents. Tentative identification of the cytokinins was based on cochromatography with synthetic cytokinin standards in several systems and on activity in the tobacco bioassay. Both the rRNA and tRNA from 10 day old pea epicotyls contained ribosylzeatin, isopentenyladenosine, and 2-methylthioribosylzeatin. The latter compound was the most active fraction in the pea rRNA, but was the least active fraction in the tRNA, where isopentenyladenosine activity was predominant. The 2-methylthioribosylzeatin from pea rRNA was identified by gas chromatography-mass spectrometry. Wheat germ rRNA contained cis and trans ribosylzeatin and 2-methylthioribosylzeatin. The tRNA contained isopentenyladenosine in addition. The specific cytokinin activity (activity per A(260) unit) of the tRNA was over forty times that of the rRNA. Significant contamination of the rRNA preparations by cytokinin-containing tRNA is considered unlikely on the basis of quantitative differences in the cytokinin content of the rRNA and tRNA preparations, electrophoretic analysis of rRNA purity and cytokinin analysis of fractionated oligonucleotide digests.

Journal Article↗

T-DNA of pTi-15955 from Agrobacterium tumefaciens is transcribed into a minimum of seven polyadenylated RNAs in a sunflower crown gall tumor.

Northern blot hybridization analysis of polysomal polyadenylated RNA isolated from sunflower crown gall tumor PSCG-15955 demonstrated that a minimum of seven RNAs were transcribed from T-DNA of pTi-15955 from Agrobacterium tumefaciens. The sizes of the T-DNA transcripts were 1.8, 1.6, 1.5, 1.1, 1.0 kilo bases (kb) and two transcripts of 0.8 kb long. The relative abundance of these polyadenylated RNAs varied greatly, the 1.0 kb RNA being the most abundant and the 1.6 kb RNA being the least abundant. Assignment of map locations of the seven polyadenylated RNAs indicated that the conserved region of T-DNA which may play a central role in tumorigenesis contained four RNAs of 1.8, 1.1, 0.8(a) and a portion of 0.8(b) kb long.

DNA Restriction Enzymes↗

Octopine synthase mRNA isolated from sunflower crown gall callus is homologous to the Ti plasmid of Agrobacterium tumefaciens.

We have shown that the structural gene for octopine synthase (a crown gall-specific enzyme) is located in a central portion of the T-DNA that came from the Ti plasmid of agrobacterium tumefaciens and is expressed after it has been transferred to the plant cells. Polyadenylylated RNA was prepared from polysomes isolated from an octopine-producing crown gall callus and purified by selective hybridization to one of five recombinant plasmids. Each such plasmid contained a different fragment of T-DNA of pTi-15955 (octopine-type Ti plasmid). Purified mRNA was translated in vitro in rabbit reticulocyte lysates, and the translation products were immunoprecipitated with antibody against octopine synthase. Total and immunoprecipitated products were characterized by their molecular weights. A polypeptide of M(r) 40,000 (the same as authentic octopine synthase) was synthesized in vitro by crown gall mRNA selectively hybridized to three of the five fragments of T-DNA and precipitated with antibody against octopine synthase. This polypeptide was not immunoprecipitated with normal rabbit antibody nor was it synthesized when mRNA from the habituated callus was substituted. A mRNA 1500 bases long was detected when total mRNA was fractionated on an agarose gel, transferred to nitrocellulose, and used for hybridization to three of the five (32)P-labeled T-DNA fragments. This apparent mRNA for octopine synthase hybridized to the same three fragments of T-DNA as the mRNA for the M(r) 40,000 polypeptide and was not detected in the habituated callus.

Journal Article↗