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Biomedical subjects

S Kawaguchi

Publications and source records attributed to S Kawaguchi.

At least 253 records · Page 14Linked to original sources
PubMed1984

Geniculocortical projection to layer I of area 17 in kittens: orthograde and retrograde HRP studies.

Using the orthograde and retrograde HRP methods, the distribution of geniculocortical (G-C) afferent terminals in area 17 was examined in kittens and an adult cat. Following HRP injection in the entire dorsal lateral geniculate nucleus (LGNd), afferent terminals were labeled in layer I and deeper layers. The terminals in layer I in young kittens (less than 2 weeks old) were densely distributed throughout layer I, whereas in old kittens (over 1 month old) they were sparsely distributed in the outer half of layer I. When the HRP injection site was confined to the A laminae (lamina A and lamina A1), a few HRP-labeled terminals in layer I were seen in young kittens but not in older kittens or an adult cat. Following HRP injection in layer I of area 17 in young kittens, relatively large neurons were labeled retrogradely. The labeled neurons were located chiefly in the C complex and partly in the A laminae. The present experiments revealed that the G-C afferents to layer I of area 17 in young kittens originate from relatively large neurons which are located chiefly in the C complex and partly in the A laminae and that these afferents give dense terminals covering the entire layer I. These findings contrast with those obtained in adult cats, in which the G-C afferents to layer I originate exclusively from small neurons in the C complex and give sparse terminals to the outer half of layer I.

Animals↗
PubMed1984

Physicochemical characterization of spray-dried phenylbutazone polymorphs.

A spray-drying method was applied to the recrystallization of phenylbutazone, and the resulting samples were examined by X-ray powder diffractometry, differential thermal analysis, IR spectrophotometry, scanning electron microscopy, and hot-stage photomicroscopy. Three different crystalline forms (delta, beta, and epsilon) could be prepared from methylene chloride solution by varying the drying temperature of sprayed droplets from 120 degrees C to 30 degrees C. Form epsilon, the fifth polymorph of phenylbutazone, was confirmed as a novel crystalline form which could not be prepared by recrystallization techniques. In this spray-drying system the composition of spray-dried samples was shown to be a function of the drying temperature. While the stable form delta was obtained at higher drying temperatures, form epsilon was obtained only under conditions affording a slower evaporation rate of the solvent. The dissolution properties of the pure modifications prepared by recrystallization techniques and the spray-dried samples were evaluated in simulated intestinal fluid. Form epsilon showed excellent in vitro availability and much higher solubility than any other of the forms.

Calorimetry↗
PubMed1984

Insulin resistance in an infant with leprechaunism.

A Japanese female infant with typical features of leprechaunism exhibited glucose intolerance despite marked hyperinsulinemia, indicating insulin resistance. Circulating insulin appeared to be chemically and biologically normal. There was no evidence of antagonism of insulin action or circulating antibodies to insulin or insulin receptors. Insulin receptor assay of her erythrocytes showed very low affinity despite a six-fold increase in the number of receptors as compared with those of normal adult controls. Our studies indicate that insulin resistance in this patient appears to be due to a qualitative abnormality of insulin receptors or to a postreceptor defect.

Abnormalities, Multiple↗
PubMed1984

Irradiation conditions required in combined radiation-microbial process for landfill leachate.

A landfill leachate, which contains large amounts of microbially refractory humic substances, was irradiated with 60Co gamma-rays under several conditions and the modification of its biodegradability was examined. The effects of initial pH and dose rate on the modification were found to be insignificant. The apparent effect was observed for the initial concentration of the humic substances. High biochemical oxygen demand (BOD) value was obtained as the initial concentration was higher. As the initial concentration was lower, in contrast, the decreasing rates of total organic carbon (TOC) and chemical oxygen demand (COD) were high. Therefore two possible designs of the combined radiation-microbial processes with and without dilution are proposed. Both processes require only about 30% of the irradiation dose, compared with a simple radiation process.

Biodegradation, Environmental↗
PubMed1983

Postnatal development of the geniculocortical projection in the cat: electrophysiological and morphological studies.

Using laminar field potential analysis, we examined responses elicited by both photic and optic nerve stimulations in 30 kittens of 0--65 days of age and in three adult cats. In adult cats, the response in the visual cortex on optic nerve stimulations is a wave complex which consists mainly of surface positive depth negative (sP-dN) potentials. By contrast, the response in neonates consists of two surface negative - depth positive (sN-dP) waves. In 2 weeks, preceding the sN-dP waves, an sP-dN wave appears. As age increases, the sP-dN wave becomes of higher voltage and the sN-dP waves become of lower voltage. Thus, the configuration of the response resembles that of adult cats in 3--4 weeks. Both photic and optic nerve stimulations elicit responses of the same configuration in the same area. The extent of the response area is exactly the same at any age as in adult cats. Using the orthograde HRP method, we examined terminals of the geniculocortical afferent in 23 kittens of 0--43 days of age. The density of labeled terminals in layer I is much higher in kittens before 1 week of age (n = 8) than in kittens after 1 month of age (n = 5), whereas the density of labeled terminals in layer IV is higher in the older kittens than in the younger kittens. These electrophysiological and morphological changes are correlated in reference to the maturation of the neuronal circuit in the visual cortex.

Aging↗
PubMed1983

Plasma exchange for treatment of intractable psoriasis.

Hemofiltration and plasma exchange, using a plasma separator with membranes, were used in 14 psoriatic patients. The efficacies of the treatments were compared. Among the patients, 13 were treated with hemofiltration and/or direct hemoperfusion, 5 experienced complete remission, 5 improved, and 3 remained unaffected. In these 3 cases, plasma exchange was performed. The first patient, who suffered from psoriasis pustulosa with arthropathica, achieved complete remission with only two treatment of 2-L plasma exchange. Joint pain was also eliminated. Both skin lesions and joint pain were markedly improved in the second patient, who suffered from psoriasis vulgaris with arthropathica. The third patient showed marked improvement with only two plasma exchanges, and is under continuing observation.

Adult↗
PubMed1983

Post-natal development of the cerebello-cerebral projection in kittens.

Post-natal development of the cerebello-cerebral response was investigated in 126 kittens from birth to 142 days of age by analysis of laminar field potentials in the cerebral cortex; the thalamocortical projection mediating the cerebello-cerebral response was examined on four new-born and three one-month-old kittens by means of anterograde axonal transport of horseradish peroxidase. A marked response was evoked in the frontal motor cortex from birth and an appreciable response could be evoked in the parietal association cortex at 2 days after birth. The latency of response in the frontal cortex decreased sharply from birth till 3 weeks of age whereas that in the parietal cortex remained almost unchanged until 2 weeks of age. Maturation of the cerebello-cerebral projection, in every respect, proceeds earlier in the frontal cortex than in the parietal cortex. The cerebello-cerebral response in kittens at any age, like in adult cats, consisted of two types of elementary responses: one which is characterized by a surface positive-depth negative (s.p.-d.n.) wave and the other which is characterized by a surface negative-depth positive (s.n.-d.p.) wave. The response in the frontal cortex was a sequential occurrence of the two waves while the responses in the parietal cortex was a pure form of the s.n.-d.p. wave. Two types of thalamocortical projections corresponding to the two types of elementary responses were revealed: one is the projection mainly onto layer I which appears to mediate the s.n.-d.p. wave and the other is the projection mainly onto layer III which appears to mediate the s.p.-d.n. wave. Development of the cerebello-cerebral response and changes in the terminal distribution of the thalamocortical projection during maturation are consistent with the principle of ontogenesis of the mammalian neocortical organization, i.e. ascending sequential maturation.

Aging↗
PubMed1983

Elimination kinetics of cefotaxime and desacetyl cefotaxime in patients with renal insufficiency and during hemodialysis.

The pharmacokinetics of cefotaxime, a new semi-synthetic cephalosporin for injection, was studied in 30 subjects with various degrees of renal function after a single 1-gram intramuscular injection. Serum and urinary concentrations of cefotaxime and desacetyl cefotaxime were determined by high pressure liquid chromatography. The pharmacokinetic parameters of cefotaxime were obtained using a one-compartment open model. The mean serum half-life of the parent compound (cefotaxime), 0.87 h in normal subjects, was prolonged to 2.35 h in hemodialysis patients. There was a significant linear correlation between the elimination rate constant of cefotaxime and creatinine clearance. The mean cumulative urinary recovery of the administered dose in the 24-hour urine was 51.7% as cefotaxime and 25.6% as desacetyl cefotaxime in normal subjects.

Adult↗
PubMed1983

[A double blind clinical trial of cefamandole and cefmetazole in complicated urinary tract infections].

We conducted a randomized double blind comparison of cefamandole (CMD) and cefmetazole (CMZ) in the treatment of 193 patients with complicated urinary tract infections. The patients received 1 gram of CMD or CMZ twice a day intravenously by drip infusion over 1 hour for 5 days. Pretreatment urinary leukocyte counts and urinary bacterial counts were at least 5 cells/hpf and 10(4) bacteria/ml, respectively. Each patient was randomly allocated either to CMD or CMZ group. There were 93 patients in CMD group and 100 patients in CMZ group. Clinical efficacy was evaluated based on the effect of treatment on bacteriuria and pyuria according to the criteria set by the UTI Committee, Japan. The response to CMD treatment was excellent in 18 cases (19.4%), moderate in 38 cases (40.9%) and poor in 37 cases (39.8%) with an overall effectiveness of 60.2%, whereas the response to CMZ was excellent in 19 cases (19.0%), moderate in 40 cases (40.0%) and poor in 41 cases (41.0%) with an overall effectiveness of 59.0%. No statistical significant difference was found between 2 treatment groups. Comparison of the bacteriological response between 2 groups showed that the eradication rate for strains of Gram-positive cocci were significantly higher in those patients treated with CMD. Gram-negative rods were eradicated from 68.4% of cases treated with CMD, and 78.0% of those with CMZ, but the difference was not significant. Adverse reactions were observed in 3 patients receiving CMD 1 case each of diarrhea, eruption and epigastric pain. Abnormality in laboratory tests was found in 6 patients in each treatment group. The results indicate that CMD is effective, safe and useful in the treatment of patients with complicated urinary tract infections, and its efficacy, safety and usefulness are comparable with those of CMZ.

Adolescent↗
PubMed1983

[Simultaneous, bilateral hypertensive intracranial hematomas].

The reported incidences of bilateral intracerebral hemorrhages due to systemic arterial hypertension are exceptionally rare in Japan. Unilateral hemorrhages, on the other hand, are less uncommon. Recently, we have examined two patients with bilateral intracerebral hemorrhages due to hypertension. The first case involved bilateral thalamic hemorrhages; and in the other, a contralateral hemorrhage developed postoperatively, subsequent to the evacuation of a primary hematoma. The characteristic neurological manifestation of bilateral intracerebral hemorrhages include quadriparesis, bilateral Babinski's signs, stupor, and coma. Published information regarding the anatomy of intracerebral hemorrhages due to hypertension is inconclusive, but the bilateral basal ganglias are believed to be most frequently involved. One school of thought explains the pathomechanism of bilateral hemorrhages as a symmetrical rupture of cerebral microaneurysm. However, it is possible that an unilateral hematoma was formed by a ruptured microaneurysm, and subsequently, a contralateral hemorrhage developed in relatively short time due to circulatory disturbance. As in the case of general cerebral hemorrhage, a craniotomy is also indicated for hypertensive bilateral intracerebral hemorrhage.

Aged↗