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Biomedical subjects

Y Taniguchi

Publications and source records attributed to Y Taniguchi.

At least 469 records · Page 26Linked to original sources
PubMed1988

Pressure effects on substrate activation phenomena in the alpha-chymotrypsin-catalyzed hydrolysis of p-nitrophenyl acetate.

With and without p-chlorophenol as an activator, the rates of hydrolysis of p-nitrophenyl acetate catalyzed by alpha-chymotrypsin were measured at pressures up to 2 kbar at 25 degrees C. From the pressure dependence of the rate constant (kcat)A and (kcat)0 of the product formation with and without an activator, the activation volumes (delta V not equal to cat)A and (delta not equal to cat)0 were +2 and -6 +/- 1 cm3.mol-1. From the pressure dependence of the equilibrium constant (KA) of incorporation of p-chlorophenol into the enzyme, the volume change (delta VA) was -10 +/- 1 cm3.mol-1. The mechanisms of the substrate activation are discussed in terms of the activation and reaction volumes.

Atmospheric Pressure↗
PubMed1988

Rapid growth of a pseudosarcoma of the esophagus.

The growth of a pseudosarcoma of the esophagus was observed chronologically by serial esophagography. Esophagograms taken 12 and 6 months prior to diagnosis showed no abnormalities. At diagnosis, the tumor in the lower esophagus had a polypoid and nodular surface with a stalk, and it was approximately 3 cm in diameter. Four months later, the tumor had increased in size to 4 cm in diameter. The tumor was 5 cm in length and incarcerated into the stomach with an elongated stalk at operation. The growth curve was linear on semilogarithmic paper; its doubling time was calculated as 2.2 months. The surgical specimen showed squamous cell carcinoma and spindle cell sarcoma-like elements that comprised the greater part of the tumor. The sarcoma-like elements had metastasized to the abdominal lymph nodes. These findings confirm that this polypoid tumor grows rapidly.

Aged↗
PubMed1988

Immunocytochemical delineation of thyrotrophic area: origin of thyrotropin-releasing hormone in the median eminence.

To identify the specific thyrotropin-releasing hormone (TRH)-containing neurons projecting to the median eminence (ME), a retrograde tracing method with horseradish peroxidase (HRP) was combined with immunocytochemical staining for TRH. Three days after HRP injection restricted to the ME, several TRH-positive neuronal perikarya were found to contain HRP. Such double-stained cells were exclusively distributed in the anterior parts of the periventricular nucleus and the most medial parts of the paraventricular nucleus. Few double-stained cells were observed in other parts of the brain examined. The present observations appear to demonstrate that the specific TRH neurons projecting to the ME are located along the border of the third ventricle, anterior to the ME.

Animals↗
PubMed1988

Anaphylactoid reaction to oxytocin during cesarean section.

A case of an allergic reaction to synthetic oxytocin administered during cesarean section is reported. Epinephrine was more effective in improving the severe hypotension than ephedrine. The incidence of anaphylactoid reaction to oxytocin is very low, but this potential problem must always be kept in mind in daily obstetric practice.

Adult↗
PubMed1988

Projection of pro-opiomelanocortin neurons from the rat arcuate nucleus to the midbrain central gray as demonstrated by double staining with retrograde labeling and immunohistochemistry.

Conjugate of horseradish peroxidase and wheat germ agglutinin (HRP-WGA conjugate) was injected into the midbrain central gray (MCG) of three adult rats. Frontal sections of the diencephalon were first treated with diaminobenzidine and hydrogen peroxide to detect the retrogradely transported conjugate. They were then stained immunohistochemically to detect pro-opiomelanocortin (POMC)-derived peptides (ACTH, beta-endorphin and alpha-MSH). The coexistence of the three POMC-derived peptides was confirmed by the immunohistochemistry of three consecutive sections stained with antiserum specific to each peptide. Some of the neuronal perikarya distributed in and around the arcuate nucleus were positive to the immunohistochemical stain for POMC-derived peptides, and, concomitantly, were labeled with HRP-WGA conjugate, which indicated that they projected to the MCG. They were mostly concentrated in the rostral three-fifths of the arcuate nucleus. The finding that some of the POMC neurons in the arcuate nucleus project to the midbrain central gray deserves interest, because the central gray is involved in analgesia induced by opioid peptides.

Adrenocorticotropic Hormone↗
PubMed1988

The distribution of vasopressin- or oxytocin-neurons projecting to the posterior pituitary as revealed by a combination of retrograde transport of horseradish peroxidase and immunohistochemistry.

The distribution of vasopressin (AVP)-containing or oxytocin (OXT)-containing neurons in the rat hypothalamus which project to the posterior pituitary was revealed by the combination of retrograde tracing of horseradish peroxidase (HRP) and immunohistochemistry. The majority of magnocellular neurons labeled with HRP were located in some of the hypothalamic nuclei, including the supraoptic nucleus and paraventricular nucleus. Many of these neurons were also immunostained by anti-AVP or anti-OXT. On the other hand, some of the immunostained neurons were not labeled with HRP in the dorso-medial and the most caudal parts of the paraventricular nucleus. These data confirmed previous reports concerning the distribution of AVP- or OXT-neurons projecting to the posterior pituitary, as a more direct visualization of both the neuropeptides and the retrogradely transported HRP in the same tissue section was attained. In addition, some of the HRP-labeled perikarya which seemed to have direct contact with the ventricular lumen were occasionally seen; its functional significance is discussed.

Animals↗
PubMed1988

[The measurement of parathyroid hormone in sera of hemodialysis patients with renal insufficiency by employing the various kinds of parathyroid hormone kits].

This study focussed on elucidating difference of blood PTH levels, by employing the various kinds of PTH kits. We carried out the measurements of PTH levels in sera of the hemodialysis patients with renal insufficiency presumably inactivated PTH degradative regulation in kidney. Our results showed the remarkable significant relationships among blood PTH levels of carboxyl and mid-region PTH and intact PTH in hemodialysis patients and was deduced that the difference of PTH levels by using various kinds of PTH kits was responsible of PTH cleavage effect in the kidney.

Adult↗
PubMed1988

[The measurements of parathyroid hormones in sera of elderly osteoporotic patients with serum high alkaline phosphatase activity].

This study was carried out to investigate effects of drugs treated in the elderly osteoporotic patients on measurements of carboxy terminal, mid-region and intact PTH, by using the various kinds of PTH kits. The drugs such as 1 alpha(OH)D3, calcitonin and so on, in the treatment of osteoporotic patients, was brought about no significant inter-relationships among carboxy terminal, mid-region and intact PTH in sera of the elderly osteoporotic patients with serum high alkaline phosphatase activity.

Aged↗
PubMed1988

[The load bearing function of patellar tendon bearing brace--on the relation between shaft length and rate of load bearing].

The load bearing function of the PTB brace was studied with emphasis on the relationship between shaft length and rate of load bearing. A PTB brace with a heel was used in this experiment, and a sliding device was attached to the shaft of the brace. Load cells were placed in the brace in the patellar tendon, anterior and posterior of the lower leg and the anterior and posterior sole. To each group of data on pressure on the load cells and vertical component of the ground reaction force, multiple regression analysis was applied to evaluate the load bearing function of the PTB brace. Results showed that 80% of non-loading was obtained at the start point of the shaft in which the load cell on the posterior sole of the brace indicated no-loading, 60% was obtained at a point 4.8 mm below the start point, 40% at 8.6 mm, and 20% at 12.3 mm.

Adult↗
PubMed1988

Two human cases of gnathostomiasis and discovery of a second intermediate host of Gnathostoma nipponicum in Japan.

Two human cases of gnathostomiasis from ingestion of raw native Japanese loaches, Misgurnus anguillicaudatus, are reported. Seven early third-stage larval Gnathostoma nipponicum were recovered from 3,098 loaches in the same district in which 2 human patients had obtained and eaten raw loaches. Encapsulated G. nipponicum larvae were also recovered from loaches infected under laboratory conditions. All 6 weasels captured in the same district in which the naturally infected loaches were found and where the humans had become infected were infected with adult worms of the same species. This is the first report of M. anguillicaudatus serving as a second intermediate host of G. nipponicum.

Animals↗
PubMed1987

Effect of pressure on the pre-steady-state kinetics of the hydrolysis of anilide substrates catalyzed by alpha-chymotrypsin.

The pre-steady-state of the hydrolysis of succinyl-L-alanyl-L-alanine p-nitroanilide (SA2pNA) and succinyl-L-alanine p-nitroanilide (SApNA) catalyzed by alpha-chymotrypsin in Tris buffer solution was measured up to 1.5 kbar at 25 degrees C. The pressure dependence of the formation of tetrahedral intermediate from the Michaelis complex on the rate constant (k1) gave activation volumes, delta V1 not equal to, of -33 +/- 2 cm3 X mol-1 for SA2pNA and -30 +/- 2 cm3 X mol-1 for SApNA. The reaction mechanism of alpha-chymotrypsin is discussed in terms of the activation volumes.

Alanine↗
PubMed1987

Activation of interleukin-2 receptor gene by forskolin and cyclic AMP analogues.

Forskolin (FK), a reversible activator of adenylate cyclase, markedly enhanced the expression of interleukin-2 receptor (IL-2-R) on a human natural killer (NK)-like cell line, YT. The FK-induced increase in IL-2-R on YT cells closely correlated with an increase in intracellular cyclic AMP (cAMP) level, and was mimicked by dibutyryl cyclic AMP (dbcAMP). FK induced both high and low affinity IL-2-R on the cells. Using a cDNA for the IL-2-R as a probe, the FK-induced IL-2-R expression was shown to be associated with an increase in IL-2-R mRNA. FK also enhanced the IL-2-R expression on a human T lymphotrophic virus I (HTLV-I) positive T-cell line (YTA-1H) and augmented the phorbol ester-induced expression of IL-2-R on HTLV-I negative T-cell lines (HSB-2 and HPB-ALL). These results suggest the possibility that the stimulation of adenylate cyclase may serve as a pathway leading to activation of the IL-2-R gene in certain types of lymphocytes.

Adenylyl Cyclases↗
PubMed1987

Ultrastructure of sheathed vessels in the retina from patients with various diseases.

Retinal sheathed vessels from five patients with various vascular diseases were examined by light and electron microscopy. All of these vessels were characterized by a marked increase and disarrangement of collagen fibrils in the media and adventitia. Cytoplasmic processes of glial cells had invaded the adventitia in sheathed vessels and even in unsheathed ones. Thickening and multilamination of the basal laminae were observed in both the sheathed and unsheathed vessels. The lumens of most sheathed vessels were still patent, and the blood cells and endothelial cells of these vessels appeared to be intact. We found no essential differences in the ultrastructure of these vessels in the five patients with various vascular diseases. It is concluded that the increase and disarrangement of collagen fibrils may be mainly related to the ophthalmoscopic appearance of the sheathing and that other factors seem to be of lesser significance.

Adult↗
PubMed1987

Establishment and characterization of a new murine mammary tumor cell line, BALB/c-MC.

A new murine mammary tumor cell line (BALB/c-MC) was established from a spontaneous mammary tumor in a 17-mo.-old female mouse of the low mammary cancer strain BALB/cHe. The cell line was derived from a papillary adenocarcinoma. In monolayer culture the line exhibits a pavementlike arrangement of cells and forms "domes" or "hemicysts" as the cells become confluent. The cell line rapidly forms tumors when transplanted into young syngeneic BALB/cHe mice. The subcutaneous injection of 10(6) cells resulted in the development of mammary tumors (typical papillary adenocarcinomas) in 33 of 37 (87%) recipients within 2 to 3 mo. after injection. These mammary tumors also metastasize to lung [14 of 33 (42%) of recipients] during this time. The number of chromosomes in this cell line is hyperdiploid (average of 43, range 39 to 44).

Adenocarcinoma, Papillary↗