PubMed Health⌕ Search

Biomedical subjects

M Yanagi

Publications and source records attributed to M Yanagi.

At least 73 records · Page 4Linked to original sources
PubMed1993

Phylogenetic analysis of the family Rhizobiaceae and related bacteria by sequencing of 16S rRNA gene using PCR and DNA sequencer.

The 16S rRNA gene sequences of 19 strains covering 97% of the molecules were determined for the members of the family Rhizobiaceae and related bacteria by PCR and DNA sequencer. The three biovars of Agrobacterium were located separately, whereas Agrobacterium rubi clustered with A. tumefaciens. Phylogenetic locations for the species of the genera Rhizobium, Sinorhizobium, Agrobacterium, Phylobacterium, Mycoplana (M. dimorpha), Ochrobactrum, Brucella and Rochalimaea (a rickettsia) were intermingled with each other with the similarity values higher than 92%. The family Rhizobiaceae should be redefined including the above-mentioned genera despite the ability for plant association and nitrogen fixation. Bradyrhizobium japonicum and Mycoplana bullata were far remote from the other species and should be excluded from this family.

Base Sequence↗
PubMed1993

Sequencing analysis of mutation points in the biotin operon of biotin-overproducing Escherichia coli mutants.

We analyzed mutation points of the biotin operon from biotin-overproducing mutants of Escherichia coli resistant to two biotin analogs, actithiazic acid and 5-(2-thienyl)-valeric acid, by DNA sequencing. The biotin operons cloned from these mutants were classified into three groups. One point mutation, which was a GC-->AT change within the operator overlapping the -10 region of the rightward (bioB) promoter, was considered to result in disruption of operator structure and enhancement of promoter activity. Two other point mutations, which were both GC-->AT changes just before and after the initiation codon of the bioB gene, were considered to activate the translation efficiency. These mutations significantly accelerated the biotin-forming activity from dethiobiotin in cell-free extracts.

Base Sequence↗
PubMed1993

[Study on safety of sodium hyaluronate (SL-1010) by injection in the anterior chamber].

We investigated effects of a newly developed sodium hyaluronate (SL-1010) on the anterior segment of the eye. The tested sodium hyaluronate was biosynthesized using Streptococcus zoo-epidemicus. Under an operating microscope, we replaced the aqueous humor of Macaca fascicularis (n = 3) with 150 microliters of 1% sodium hyaluronate solution without loss of the anterior chamber. The opposite eye was treated as a control and its aqueous was replaced with the same volume of the vehicle, isotonic phosphate buffer solution. We performed follow-up clinical examination with slit-lamp microscopy, pachymetry, pneumotonometery, and specular microscopy. On the 7th day, we performed histological study by light microscopy, transmission and scanning electron microscopy. Although the sodium hyaluronate group showed a significant increase of intraocular pressure at 9 hours after the treatment over the control, there were no significant differences in clinical findings between the sodium hyaluronate and the control groups. Histological studies demonstrated nothing particular except for slight swelling of mitochondria of corneal endothelial cells in both groups. It was concluded that the newly developed sodium hyaluronate is a biologically inactive and safe biomaterial.

Animals↗
PubMed1993

[A case of chondrosarcoma of the thoracic vertebra].

A case of chondrosarcoma of the thoracic vertebra in a 47-year-old female is described. Chest X-ray, CT and MRI disclosed an abnormal mass lesion in the posterior mediastinum. The lesion was surgically removed through right thoracotomy. The operative findings revealed that the lesion, hard and measuring 6.5 x 4.5 x 4.5 cm in diameter, was originated from the 7th and 8th thoracic vertebra. The lesion was histopathologically diagnosed chondrosarcoma. The chondrosarcoma arising from the thoracic vertebra is very rare, and only 10 cases have hitherto been reported in the Japanese literature.

Chondrosarcoma↗
PubMed1993

High-risk groups and screening strategies for early detection of hepatocellular carcinoma in patients with chronic liver disease.

Characteristics of high-risk groups for hepatocellular carcinoma (HCC) in Japan were studied to establish screening strategies for early detection of the tumor. Some 93% of patients with HCC were associated with chronic liver disease. On the other hand, 67% of patients with liver cirrhosis had HCC at autopsy. Most were related to current hepatitis virus infection. An analysis of risk factors among 120 patients with chronic hepatitis revealed that age and histological findings were independent risk factors, while HBsAg, anti-HCV, sex, history of heavy drinking, history of blood transfusion were not independent risk factors. Multivariate analysis of 239 patients with liver cirrhosis demonstrated that age, positivity for HBsAg and/or anti-HCV, family history of liver disease, hepatic reserve, and a history of radical resection were independent factors related to the development of HCC. A screening schedule for cirrhotic patients was established in accordance with these results; ultrasonography was done every three months, and tumor markers measured every two months. The screening strategy proved to be effective for the early detection of HCC and improvement of the prognosis.

Aged↗
PubMed1992

Conversion of dethiobiotin to biotin in cell-free extracts of Escherichia coli.

We constructed the plasmid pTTB151 in which the E. coli bioB gene was expressed under the control of the tac promoter. Conversion of dethiobiotin to biotin was demonstrated in cell-free extracts of E. coli carrying this plasmid. The requirements for this biotin-forming reaction included fructose-1,6-bisphosphate, Fe2+, S-adenosyl-L-methionine, NADPH, and KCl, as well as dethiobiotin as the substrate. The enzymes were partially purified from cell-free extracts by a procedure involving ammonium sulfate fractionation. Our results suggest that an unidentified enzyme(s) besides the bioB gene product is obligatory for the conversion of dethiobiotin to biotin.

Base Sequence↗
PubMed1991

Gene structure of heat shock proteins 61KDa and 12KDa (thermophilic chaperonins) of thermophilic bacterium PS3.

Heat shock proteins 60 (hsp60) and 10 (hsp10) are essential for the formation and restoration of many supramolecular structures. For reconstitution of these structures, we isolated stable hsps of 61kDa and 12kDa, which are similar to hsp60 and hsp10, respectively, from the supernatant fraction of thermophilic bacterium PS3 by ATP-Agarose chromatography. Using synthetic DNA of the deduced sequence, the 1.6kbp double stranded DNA encoding both proteins was obtained by the polymerase chain reaction (PCR). The complete sequence of the resulting reading frames showed high homology to those of the genes encoding GroEL (hsp60) and GroES (hsp10) of E. coli, and hsp60s and hsp10s of several other species. The genes for the 12K and 61K were present in the same operon. 61K was also partially similar to the F1 alpha subunit of thermophilic ATP synthase, which is highly reconstitutable to form the alpha beta complex.

Amino Acid Sequence↗
PubMed1990

Two enzymes concerned in peptide hormone alpha-amidation are synthesized from a single mRNA.

By expressing truncated rat pituitary 'peptidylglycine alpha-amidating enzyme' cDNAs in COS-7 cells, we found that the two reactions concerned in peptide carboxyl-terminal amidation, namely the peptidylglycine alpha-hydroxylation reaction and the peptidyl-hydroxyglycine amidation reaction, were catalyzed by 37- and 53-K proteins, which were derived from the 5'- and 3'-coding sequences, respectively. The full-length cDNA directed the expression of both the 37- and 53-K enzymes, and in the combined presence of the two enzymes the full conversion of a glycine-extended peptide into the amidated product was achieved. These results indicated that two enzymes concerned in peptide hormone alpha-amidation are generated from a common precursor protein encoded by a single mRNA.

Amino Acid Sequence↗
PubMed1990

The reaction product of peptidylglycine alpha-amidating enzyme is a hydroxyl derivative at alpha-carbon of the carboxyl-terminal glycine.

The peptidylglycine alpha-amidating enzyme catalyzes a reaction that transforms a carboxyl-terminal glycine-extended precursor into a carboxyl-terminal alpha-amidated peptide. We purified an alpha-amidating enzyme from equine serum by simplified steps including substrate affinity chromatography. With the purified enzyme, we detected an intermediate of the alpha-amidating reaction by high performance liquid chromatography analysis. The production of the intermediate required copper, oxygen, and ascorbate and increased linearly with incubation time. The structure of the intermediate was determined to be a hydroxyl derivative at the carboxyl-terminal glycine by fast atom bombardment mass spectrometry and by proton NMR. The intermediate was readily converted into an alpha-amidated product in alkaline conditions in a nonenzymic fashion. The nonenzymic conversion required no cofactor but was extremely accelerated by the addition of copper ion or at higher temperature. Our data suggest that the direct product of the alpha-amidating reaction is not an alpha-amidated peptide but a hydroxyl derivative at the alpha-carbon of the carboxyl-terminal glycine.

Amino Acid Sequence↗
PubMed1985

[Clinical study on the measurement of squamous cell carcinoma (SCC)--related antigen in SCC].

By using a RIA Kit for squamous cell carcinoma (SCC) antigen, extracted and purified this substance from liver metastasis of SCC of the uterine cervix, a fundamental and clinical study has been done. Based on the fundamental study, it was shown that this kit was useful clinically. High concentrations of serum SCC related antigen were observed in squamous cell carcinoma of the lung, head and neck, and uterus. It was recognized that the measurement of serum SCC related antigen was useful in not only diagnosis, but also in the evaluation of effectiveness of therapy or prediction of recurrence. In particular, as there is a lack of reliable tumor markers in head and neck tumors, good results can be anticipated from the measurement of SCC related antigen in such cases.

Aged↗
PubMed1985

[Clinical study of the measurement of tissue polypeptide antigen in patients with breast cancer].

Tissue polypeptide antigen (TPA) concentrations in patients with breast cancer were measured using a radioimmunoassay (RIA) kit. Although this RIA kit presented some problems in the dilution test of high-concentration samples, it was found to be adequate for clinical use. It was shown that the measurement of serum TPA concentration was useful in monitoring the local recurrence, for the early diagnosis of distant metastasis and for evaluating the therapeutical effect after surgery. TPA concentration showed no correlation with CEA concentration. Therefore, in order to raise the rate of diagnostic success, simultaneous measurement of both TPA and CEA was essential.

Adult↗