PubMed Health⌕ Search

Biomedical subjects

H Kitano

Publications and source records attributed to H Kitano.

27 records · Page 2Linked to original sources
PubMed1985

Binding of serum proteins to polymer gels. II. Binding mechanism to polyoxyphenol-formaldehyde gels.

The binding mechanism of proteins to an amorphous polymer gel [formaldehyde-hydroquinone (FA-HQ)], which is a product of addition condensation of hydroquinone with formaldehyde, is examined. Proteins such as serum albumin and gamma-globulin bound to the FA-HQ gel rapidly and irreversibly (without elution by acid, alkali, urea, or detergent solution). The binding of a modified bovine albumin to the FA-HQ gel showed that the blocking of the amino groups in the albumin molecule decreased the amount of protein bound to the gel. Amino acids bound to the FA-HQ gel to a larger extent at alkaline than at neutral pH. These results supported the essential role of the amino groups in binding to the FA-HQ gel. Using the FA-HQ gel-packed glass column or polymer tube, rapid and complete removal of proteins from serum could be carried out, which suggests the usefulness of the gel for the easy pretreatment of biological samples for clinical assays using immobilized enzyme columns.

Amino Acids↗
PubMed1985

Inhibitory effect of ouabain on the palytoxin-induced contraction of human umbilical artery.

Palytoxin (PTX), C129H223O3N54, isolated from marine coelenterates of Palythoa tuberculosa, caused contraction of the human umbilical artery in a dose-dependent manner (10(-11)-10(-8) M). Pretreatment with ouabain (10(-5) M) abolished the PTX (10(-8) M)-induced contraction but had no effect on the serotonin- (10(-6) M) and potassium- (40 mM) induced contractions. When the muscle was exposed to a potassium-free medium, application of PTX was able to cause a contraction similar to the contraction in normal medium. In the presence of verapamil (3 X 10(-6) M) or in the calcium-free medium. PTX-induced contraction was inhibited. In the depolarized muscle with 126 mM potassium, PTX did not induce a contraction whereas serotonin did. Our results suggest that PTX causes calcium influx through the plasma membrane of the umbilical artery, causing contraction. The site of action of PTX is presumably related to the Na,K-ATPase on the plasma membrane, although the precise relation between the site of action and increase in calcium influx is not known now.

Acrylamides↗
PubMed1985

Pressure effects on catalysis by alkaline phosphatase reconstituted in lipid bilayers.

Bovine intestinal alkaline phosphatase (EC 3.1.3.1) was reconstituted into lipid bilayers by a dilution method using n-octylglucopyranoside. From the kinetic measurements at various pressures, the volume of activation (delta V not equal to) and volume change in substrate binding (delta V) were estimated for free and reconstituted ALP. The delta V not equal to and delta V values for free ALP and reconstituted ALP in the gel state liposome showed opposite tendencies (-23 ml . mol-1 [delta V not equal to], 35 ml . mol-1 [delta V] for free ALP and 27 ml . mol-1 [delta V not equal to], -36 ml . mol-1 [delta V] for reconstituted ALP, respectively), which suggest both strong desolvation effect of enzyme molecule by the surrounding lipids and drastic conformational change of the enzyme molecule by the reconstitution into liposomes.

Alkaline Phosphatase↗
PubMed1977

The results of penicillin G Administration of chronic unrestrained cats: electrographic and behavioral observations.

Intramuscular administration of penicillin G was carried out in a series of 27 chronic cat preparations. In addition to the EEG, the high frequency components of cerebral electrical activity were also recorded from cortical and deep structures. Videotape recordings using split-screen technique allowed correlations of the animal's clinical state with the EEG. The results showed that 'spike-wave' type activity occurred earliest in the cortex. The discharges were also best formed in cortical and thalamic structures. The other deep structures showed characteristic bursting, but not of the 'spikewave' type variety. The cerebellum showed also early participation. Clinical expressivity of the bursts depended upon the state of alertness of the animal, the height of the spike components and the extent of depth participation. The high frequency recordings revealed characteristic alternation of decrease and increase in activity mostly in cortical structures and to a lesser extent in thalamus. Pontine and medullary reticular formation areas showed usually no changes in the high frequency records during the bursts. When major seizures were induced, they were always of focal onset rather than of the primary generalized type as one sees with pentylenetetrazol. Different cortical or deep structures served as the initiating site in different animals. It was concluded that systemic penicillin adminstration does not lead to a truly primary generalized form of epilepsy, but produces its effects by multifocal activation of various cerebral structures, with cortex and cerebullum usually showing earliest involvement.

Animals↗
PubMed1976

A comparison of the effectiveness of primidone versus carbamazepine in epileptic outpatients.

Prior to the release of carbamazepine for the treatment of patients with psychomotor and grand mal seizures, primidone was regarded as the drug of choice for these disorders, especially when combined with diphenylhydantoin (DPH). It was, therefore, of interest to compare the effectiveness of carbamazepine against primidone when added to a therapeutic dose of DPH. Forty-five patients completed a 6-month study with each patient serving as his own control. The patients were initially stabilized on therapeutic doses of DPH and one of the test compounds, while all other medications were withdrawn. After 3 months of treatment, they were transferred onto the other drug for a second 3-month period. Extensive laboratory testing, including anticonvulsant levels, electroencephalograms, and neuropsychological evaluations, was performed. For the most part, the patients remained on outpatient status, returning for reports of seizure frequency, side effects, and laboratory studies every 14 days. The study was conducted in a single blind fashion by the treating neurologists; double blind by the electroencephalographer and psychologists. The results indicated that the two drugs did not differ in their effectiveness on seizure control. There were somewhat more side effects--none serious--with carbamazepine than with primidone. The EEG showed increased fast activity with primidone and increased theta activity with carbamazepine. There was no difference in regard to decrease of electroencephalographic seizure discharges. The patients showed more impairment on a repeatable neuropsychological test battery with primidone than with carbamazepine, and they also showed an increase on the psychopathic deviate scale of the Minnesota Multiphasic Inventory. Depressive feelings, when present, lessened while under treatment with carbamazepine. The results suggest that patients with the seizure types under consideration and who do not respond to DPH alone or to a DPH-phenobarbital combination can be placed on either carbamazepine or primidone while phenobarbital is discontinued. A patient who is intellectually and emotionally intact with no past history of behavioral disturbances may do better on primidone than carbamazepine, because this drug gives fewer side effects. On the other hand, those patients who have a past history of emotional and/or intellectual disturbances may profit more from carbamazepine.

Adolescent↗