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Biomedical subjects

Y Sano

Publications and source records attributed to Y Sano.

At least 289 records · Page 16Linked to original sources
PubMed1988

Hypothalamic digitalis-like substance is released with sodium-loading in rats.

Role of the hypothalamic digitalis-like substance (EDLS) on the hypertension associated with an excess intake of sodium and the releasing mechanism were investigated. The blood pressure in rats fed with a sodium diet increased significantly after 4 weeks of the treatment compared to the control rats fed with a regular diet, which was accompanied by increased urinary output of the EDLS. Electrical lesions of the AV3V area in the hypothalamus significantly decreased both the urinary EDLS level and the blood pressure elevated by the sodium-loading. With the immunohistochemistry using digoxin antibody, the immunoreactives were localized in the neurons of paraventricular and supraoptic nuclei and some other hypothalamic areas, and were also seen in the nerve fibers distributed in the basal hypothalamus, infundibulum, and pituitary posterior lobe. Assuming that the CSF sodium is responsible for the release of EDLS, hypertonic NaCl (2.5 M) was infused into the lateral ventricle for 30 minutes. Blood pressure increased gradually, attaining peak rises about 30 minutes later. The plasma content of the EDLS was significantly greater in the hypertonic NaCl group than the control group treated with either the artificial CSF or 2.5 M of urea solution. On the other hand, the hypothalamic content decreased with the infusion of the hypertonic saline. Furthermore, the continuous intracerebroventricular infusions of the hypertonic NaCl with osmotic minipumps in conscious rats significantly increased the arterial pressure after 6 days. Thereby, the plasma level of the EDLS was significantly greater than the control rats that received only the artificial CSF.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Digitalis-like substance is produced in the hypothalamus but not in the adrenal gland in rats.

We studied the role of the adrenals on the plasma levels and urinary output of the digoxin-like immunoreactivity in order to elucidate the interrelationship between the adrenals and hypothalamic digoxin-like immunoreactivity. Urine was collected for 24 h 6 days after the bilateral adrenalectomy and then rats were killed by decapitation. Urinary excretion of digoxin-like immunoreactivity did not differ significantly between the sham-operated and adrenalectomized groups, regardless of sodium intake. Plasma levels did not change significantly with sodium-loading, and adrenalectomy did not significantly affect the plasma concentrations of the immunoreactivity. However, bilateral adrenalectomy increased the content of digoxin-like immunoreactivity in the hypothalamus significantly in both rat groups fed with a regular (P less than 0.05) and a high-salt (P less than 0.02) diet. However, when the levels were measured only 16 h after bilateral adrenalectomy, both plasma and hypothalamic contents were significantly higher in the high-salt than the regular-salt group. The correlation between the plasma and hypothalamic content was significant (P less than 0.01). These results strongly suggest that digoxin-like immunoreactivity is produced in the hypothalamus but not in the adrenals, and that the adrenal glands influence the turnover of the hypothalamic endogenous digitalis-like substance.

Adrenal Glands↗
PubMed1988

Neonatal hemophilia B with intracranial hemorrhage. Case report.

It is uncommon for infants with hemophilia to have excessive bleeding during the neonatal period. Even if bleeding occurs, it rarely becomes life-threatening, such as in intracranial hemorrhage (ICH). We here report a case of a 4-day-old boy who had intracranial hemorrhage as the first complication of hemophilia B. Computerized axial tomography (CT scan) and ultrasonography were very useful for early diagnosis. Only a few cases of neonatal hemophilia with intracranial hemorrhage have been reported, but the occurrence of this complication is probably more frequent. We reviewed seven cases (including our case) with intracranial hemorrhage as the first manifestation of neonatal hemophilia. Although these infants showed good prognosis as to survival, permanent residual neurological deficits remained in all of them. It is emphasized that intracranial hemorrhage due to hemophilia may occur in neonates even without a family history. Urgent neuroimaging and coagulation studies are necessary for an early and adequate diagnosis.

Cerebral Hemorrhage↗
PubMed1988

Solubilization and characterization of calcitonin gene-related peptide binding site from porcine spinal cord.

The binding site for calcitonin gene-related peptide (CGRP) was solubilized with 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS) in an active form from porcine spinal cord. 125I-labeled human alpha-CGRP (125I-CGRP) binding to the solubilized protein was determined by filtration using a GF/B glass filter. The maximal binding activity (approximately 60% of the crude membrane fraction) was obtained with 5 mM CHAPS. 125I-CGRP binding to the solubilized protein was of high affinity, saturability, and high specificity, having KD and Bmax values of 3.69 pM and 338 fmol/mg of protein, respectively. The binding activity was eluted in a single peak with a molecular mass of 400,000 daltons by gel filtration on TSK gel G4000SW. These results suggest that the solubilized protein may be responsible for the specific binding site.

Animals↗
PubMed1988

Immunohistochemical demonstration of serotonin-containing nerve fibers in the mammalian hippocampal formation.

The distributional pattern of serotonin-immunoreactive nerve fibers in the hippocampal formation of six different mammalian species (rat, chipmunk, hamster, cat, dog and monkey) was studied in detail by means of a modified peroxidase-antiperoxidase immunohistochemical method, using a specific serotonin antiserum. Furthermore, the density of varicosities distributed in each layer of the hippocampus was semiquantitatively analyzed. In all species investigated, the routes of serotonin fibers entering the hippocampal formation were found to be almost the same. These fibers were extensively distributed throughout the hippocampal formation, and had a characteristic arrangement corresponding to the laminar structure of this region. A dense innervation by varicose serotonin fibers was found in the stratum lacunosum-moleculare, but a few serotonin fibers were also distributed in the stratum lucidum of the CA2 and CA3 fields. The stratum pyramidale and the granule cell layer of the dentate gyrus contained a small number of serotonin fibers. The concentration and the direction of serotonin fibers were different in each area of each animal. Two peculiar observations should be stressed: (1) in the rat, the strata oriens and radiatum of CA2 and CA3 as well as the stratum lacunosum-moleculare displayed abundant serotonin fibers; (2) in the dog, abundant serotonin fibers were diffusely distributed in the CA1 field except for the stratum pyramidale and the most dense concentration of serotonin fibers was seen in the stratum oriens of CA3. The present study provides a morphological basis for further study of the functional significance of serotonin in the limbic system.

Animals↗
PubMed1988

Immunohistochemical studies on the distribution of endogenous digitalis-like substance (EDLS)-containing neurons in the rat hypothalamus, with special consideration on the possibility of their coexistence with posterior lobe hormones.

The distribution of the perikarya of endogenous digitalis-like substance (EDLS)-containing neurons in the rat hypothalamus was studied by immunohistochemistry using digoxin and digitoxin antiserum. In addition, the possible coexistence of EDLS and posterior lobe hormones was examined using an immunohistochemical double-staining technique. Digoxin-like immunoreactive neurons were demonstrated in the paraventricular and supraoptic nuclei and other hypothalamic areas. However, digitoxin-like immunoreactive neurons were not detected in the hypothalamus. A portion of the digoxin-like immunoreactive neurons showed immunoreactivity for vasopressin or oxytocin. From these results, it is suggested that these digoxin-like immunoreactive neurons correspond to "EDLS-producing neurons," and that EDLS seems to act not only as a natriuretic substance but also as a neurohormone or neurotransmitter.

Animals↗
PubMed1988

[Concentrations of cefuroxime in the skin].

Concentrations of cefuroxime (CXM) in the skin and the serum of 24 patients were examined. CXM (0.75 g, 1.5 g) was administered to these patients intravenously in one shot. The skin and the serum were collected at 30 and 60 minutes after the injection. Concentrations of CXM in the skin were following: 0.75 g, 30 min.; 11.4 +/- 5.3 micrograms/g 60 min.; 9.5 +/- 4.7 micrograms/g 1.5 g, 30 min.; 17.1 +/- 6.8 micrograms/g 60 min.; 15.7 +/- 13.2 micrograms/g Concentration ratios (skin/serum) at 60 minutes after the injection were from 72.5% to 79.2%. The binding ratio of CXM to serum protein was 41%, which was lower than most other antibiotics. High concentration levels of CXM were maintained in the skin for a long time. Based on this study, we consider that CXM is effective in the skin surgery.

Cefuroxime↗
PubMed1987

Resolution of proteins in linear gradient elution ion-exchange and hydrophobic interaction chromatography.

The following equation was derived for the resolution, Rs, of proteins in linear gradient elution ion-exchange and hydrophobic interaction chromatography: Rs alpha [(column length.molecular diffusivity)/(slope of the gradient.column gel volume.linear mobile phase velocity.particle diameter2)]1/2. Experimental results obtained under a wide range of experimental conditions (column length, 1-30 cm; particle diameter, 37-92 micron; linear mobile phase velocity, 0.2-3.5 cm/min; temperature, 15-35 degrees C) have shown that this relationship is valid except for very short columns with a shallow slope of the gradient and for low flow-rates. The relationship is very useful for scaling-up the linear gradient elution of proteins from data obtained with small columns.

Chromatography, Ion Exchange↗
PubMed1987

Immunohistochemical demonstration of serotonergic and peptidergic nerve fibers in the subcommissural organ of the dog.

The distributional patterns of serotonin-, luteinizing hormone-releasing hormone (LHRH)-, oxytocin (OXT)- and vasopressin (VP)-immunoreactive nerve fibers were studied in the subcommissural organ (SCO) of the dog by use of the peroxidase-antiperoxidase technique. Abundant serotonergic and moderate numbers of peptidergic nerve fibers running toward the ventricular surface were observed among the cylindrical ependymal cells in the SCO of the dog. Concerning the distributional density of the peptidergic nerve fibers, VP-immunoreactive fibers displayed the highest and LHRH-immunoreactive fibers the lowest values. Most serotonergic and peptidergic fibers returned to the basal portion of the SCO after forming loops immediately beneath the ventricular surface of the ependymal layer. Serotonin-immunoreactive fibers often established a perivascular plexus around the blood vessels in the SCO. At the electron-microscopic level, after use of antiserum to serotonin dark immunoprecipitate was observed in large granular vesicles and the matrix surrounding small and large, clear vesicles and mitochondria; VP immunoreactivity was localized in the large granular vesicles. Serotonergic nerve fibers could be detected in the SCO of the newborn dog. Although the distributional density was in principle not different from that in the adult animal, individual fibers showed immature features such as growth cones and insufficiently swollen varicosities. After penetrating into the ventricle, in the newborn dog, a few serotonin-immunoreactive fibers ran for a relatively long distance on the ependymal surface.

Aging↗
PubMed1987

Light and electron microscopic immunohistochemical studies of serotonin nerve fibers in the substantia nigra of the rat, cat and monkey.

The distribution of serotonin-containing nerve fibers in the substantia nigra of the rat, cat and monkey was studied with a highly sensitive peroxidase-antiperoxidase immunohistochemical method. Serotonin fibers in the substantia nigra of all species consisted of fine varicose fibers and formed a fine network. In the zona compacta of all species, serotonin fibers were sparsely distributed. In the zona reticularis of the rat and cat, these fibers were densely distributed and their distributional pattern was almost uniform, while in the monkey such fibers were unevenly distributed and high and low dense areas were intermingled. In the pars lateralis of all species, serotonin fibers were diffusely distributed, and the distributional density was much higher in the cat and monkey than in the rat. Immunoelectron-microscopic studies further revealed that a majority of the labeled varicosities in the rat substantia nigra were in close apposition to peridendritic axon terminals and were also free in the neuropil; occasionally they exhibited symmetrical synapses of "en passant" type with non-immunoreactive dendrites or somata. Our results support a functional significance of serotonergic regulation of the substantia nigra in mammals.

Animals↗
PubMed1987

The sequence and function of the recA gene and its protein in Pseudomonas aeruginosa PAO.

The recA gene of Pseudomonas aeruginosa has been isolated and its nucleotide sequence has been determined. The coding region of the recA gene has 1038 bp specifying 346 amino acids. The recA protein of P. aeruginosa showed a striking homology with that of Escherichia coli except for the carboxy-terminal region both at the nucleotide and amino acid level. The recA+-carrying plasmids restored the UV sensitivity and recombination ability of several rec mutants of P. aeruginosa. The precise location of the recA gene on the chromosome was deduced from the analysis of R' plasmids.

Amino Acid Sequence↗