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Biomedical subjects

S Kataoka

Publications and source records attributed to S Kataoka.

At least 127 records · Page 7Linked to original sources
PubMed1989

Functions of the COOH-terminal region of cyclodextrin glucanotransferase of alkalophilic Bacillus sp. #1011: relation to catalyzing activity and pH stability.

Cyclodextrin glucanotransferase (beta-CGTase) of alkalophilic Bacillus sp. #1011 degrades starch to mainly beta-cyclodextrin (beta-CD). This enzyme is considered to contain an extra-polypeptide in its COOH-terminal region in addition to its NH2-terminal domain which exhibits the starch-degrading activity. To analyze the functions of this extra-polypeptide in the beta-CGTase, two mutated enzymes, in which DNA regions encoding 10 or 13 amino acids from the COOH-terminus were deleted, were obtained. The mutated enzymes degraded starch to glucose, maltooligosaccharides and alpha-CD, in addition to beta-CD. Furthermore, the pH stability of the mutated enzymes in the alkaline pH range (pH 9-11) was reduced.

Bacillus↗
PubMed1989

Brain stem type neuro-Behçet's syndrome. Correlation of enhanced CT scans and MRI during the acute and chronic stage of the illness.

Brain stem type neuro-Behçet's syndrome was studied with enhanced CT and MRI during the acute and chronic stage of the illness. During the acute stage, brain CT revealed a low density lesion in the brain stem extending from the lower pons up to the midbrain ventrolaterally with marginal enhancement effect. T2-weighted image showed a high signal intensity lesion in the brain stem which mainly involved the basis ponti, tegmentum, tectum and cerebral peduncle. During the chronic stage, the lesion became low in signal intensity with T2-weighted image and reduced in its size without enhancement in brain CT. The prolonged relaxation time of the lesions was gradually normalized with steroid treatment. Sequential brain CT with enhancement and MRI study with T1- and T2-weighted images were useful to detect the lesions and to evaluate the activity in the neuro-Behçet's syndrome.

Adult↗
PubMed1989

Cytotoxic effect of 8-amino adenosine 3',5'-cyclic monophosphate on FM3A mouse mammary tumor cells.

Derivatives of adenosine 3',5'-cyclic monophosphate (cAMP) with modifications at the 8-position were synthesized and examined for their cytotoxic effects on FM3A mouse mammary tumor cells and ZR-75 human mammary tumor cells. On in vitro tests of these derivatives, 8-amino (8-NH2) cAMP was the most effective against both cell lines. This compound showed the dose-dependent inhibition of FM3A cell growth in the concentration of over 2.5 microM with the ID50 value of 4 microM. Furthermore, antitumor activity of 8-NH2 cAMP was also tested against FM3A cells in vivo. T/C% values of 8-NH2 cAMP were respectively 162% and 138% in response to doses of 30 and 10 mg/kg by intraperitoneal injections of 8-NH2 cAMP for 5 d. 8-NH2 cAMP was converted to 8-NH2 adenosine via 8-NH2 adenosine 5'-monophosphate by some enzymes in the fetal bovine serum and the cytotoxic effect of 8-NH2 cAMP on FM3A cells was actually stemmed from 8-NH2 adenosine.

Animals↗
PubMed1989

[Statistical observation of crowns and bridges in Matsumoto Dental College].

A study was made of 11,425 crowns and 2,385 bridges which had been fabricated for 5,588 patients at the Prosthetic Clinic of Matsumoto Dental College during the fourteen-year period, from January 1973 to December 1986. Some of the results were as follows: 1. 753 patients, 1,585 crowns and 372 bridges in 1983 were the most numerous in all the survey years. 2. The rate of vital teeth of crowns has increased from 1984. 3. Of crowns, 22.1% and of bridge retainers, 22.3% were fabricated as porcelain fused to metal crown in 1985. 4. The rate of resin facing crowns of crowns and bridge retainers increased sharply in 1986. 5. Of crowns, 19.0% and of bridge retainers, 30.5% were fabricated as partial coverage crowns in 1986. 6. The rate of more than 5-unit bridges increased from 1982 to 1985.

Crowns↗
PubMed1989

Alkylated cAMP derivatives: selective synthesis and biological activities.

Many alkylated cAMPs have been prepared and tested for their antitumor and cardiac activities. Treatment of cAMP with several bases and alkyl bromides gave alkyltriesters of cAMP (2), N6,N6,2'-O-trialkyl cAMPs (3), N6,2'-O-dialkyl cAMPs (4) and 2'-O-monoalkyl cAMPs (5) in one step. N6,N6-dialkyl cAMPs (6) were prepared from 2'-O-tosyl cAMP by the similar alkylation, followed by detosylation. Synthesis of N6-monoalkyl cAMPs (7) was achieved by the reductive alkylation of cAMP with aldehydes in one step. Alkyl triesters of cAMP exhibited antitumor activities against P815 cells. N6-mono and N6,N6-dialkyl cAMPs showed significant cardiac activities.

Alkylation↗
PubMed1988

Derivation and termination of fusiform vesicles in the transitional epithelium of the rat urinary bladder.

Ultrastructural behavior of fusiform vesicles with an asymmetrical unit membrane in the rat transitional epithelium was investigated by in situ injection of gold colloidal particles and gold-labeled Ricinus communis lectin, and by section staining with the lectin. These experiments suggest that the fusiform vesicles are not formed from the luminal cell membrane by contraction of the urinary bladder, and that old luminal cell membranes are removed via multivesicular bodies.

Animals↗
PubMed1988

[Purification of prostatic acid phosphatase and prostate specific antigen from human seminal plasma].

Prostatic acid phosphatase (PAP) and prostate specific antigen (PA), which are useful markers of diagnosis for prostatic cancer, have been purified from human seminal plasma. Total of 54.4 mg PAP and 3.0 mg PA were purified from 426.5 ml human seminal plasma. The purified antigens were demonstrated a single band by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), having a molecular weight of about 50,000 and 34,000, respectively. The PAP and PA purified from human seminal plasma were considered similar to that of prostatic tissue immunologically and biochemically.

Acid Phosphatase↗
PubMed1987

Quantitative analysis of glucose after transient ischemia in the gerbil hippocampus by light and electron microscope radioautography.

Changes in glucose uptake in the gerbil hippocampus were studied by high-resolution [3H]2-deoxyglucose radioautography under sham and postischemic conditions. Sections of dorsal hippocampi were fixed by chemical fixatives or rapid-freezing and freeze-substitution techniques. Light and electron microscope radioautograms showed that the cell soma of each CA1 neuron subjected to transient ischemia revealed various degrees of glucose uptake. In the neuropil of the CA1 stratum radiatum, glucose uptake was higher in the thin dendrites of the ischemic group. Cell damage due to transsynaptic stimulation is suggested by these results.

Animals↗
PubMed1987

Nucleotide sequence of the beta-cyclodextrin glucanotransferase gene of alkalophilic Bacillus sp. strain 1011 and similarity of its amino acid sequence to those of alpha-amylases.

The nucleotide sequence of the gene for cyclodextrin glucanotransferase of alkalophilic Bacillus sp. strain 1011 was determined. The deduced amino acid sequence at the NH2-terminal side of the enzyme showed a high homology with the sequences of alpha-amylase in the three regions which constitutes the active centers of alpha-amylases.

Amino Acid Sequence↗
PubMed1987

Serotonergic efferent nerve fibers in the retinal plexiform layer of the abalone.

Serotonin (5-HT)-immunohistochemistries at light- and electron-microscopic levels, using rabbit anti-5-HT serum (#1234), were applied to the whole head and only to the eye of the abalone, respectively. Peroxidase-antiperoxidase and fluorescein isothiocyanate methods were used for the light-microscopic immunohistochemistries. Many immunoreactive nerve fibers were demonstrated in the outer zone of the retinal plexiform layer, small optic nerve fiber bundles, the optic nerve trunk and the cerebral ganglion. Immunoreactive somata were observed only in the cerebral ganglion. Accordingly the immunoreactive fibers in the retinal plexiform layer are considered to be efferent. Cored vesicles in the retinal plexiform layer demonstrated by both conventional chemofixation and a rapid-freeze-substitution method showed strong immunoreactivities localized within their limiting membrane. The same fibers also contained small clear vesicles. They are considered to be different from larger clear vesicles in non-immunoreactive fibers reportedly containing acetylcholine. The function of the efferent fibers remains to be elucidated.

Animals↗