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Biomedical subjects

I Yoshida

Publications and source records attributed to I Yoshida.

At least 235 records · Page 13Linked to original sources
PubMed1989

The occurrence of intramitochondrial Ca2+ granules in valproate-induced liver injury.

Two epileptic patients treated with anticonvulsants of valproic acid, phenobarbital, nitrazepam, and diphenylhydantoin developed anorexia, convulsions, and unconsciousness. The liver biopsy samples showed degenerated hepatocytes containing enlarged mitochondria with a distorted matrix. The matrix granules in the mitochondria were enlarged in size as compared with those of chronic hepatitis (Po = 0.0009). X-ray microanalysis has revealed the presence of calcium in large mitochondrial matrix granules. Both patients were thought to have valproic acid intoxication because they recovered quickly after the withdrawal of valproic acid.

Calcium↗
PubMed1989

Effects of drugs and fatty acids related to Reye syndrome on brain water content in rats.

Brain water content was measured by gas-chromatography in rats following intraperitoneal injection of drugs and fatty acids related to the etiology of Reye syndrome. A statistically significant increase in brain water content was observed following injection of 5% glucose solution, valproic acid, acetyl salicylic acid, calcium hopantenate, margosa oil, 4-pentenoic acid, linolenate and arachidonate. Seizures occurred in all animals given valproic acid, margosa oil and 4-pentenoic acid, and in 25% of those given 5% glucose solution + anti-diuretic hormone. The results of these studies may help in the selection of appropriate agents for experimental induction of acute encephalopathy and brain edema in animal models of Reye syndrome.

Animals↗
PubMed1989

[Two cases of scleroderma associated with vibration syndrome].

Case 1, a 49-year-old male who had been engaged in repair and reclamation of automobile tires, developed symptoms of vibration syndrome (Raynaud's phenomenon, numbness of both hands, tinnitus and impaired hearing) after some 30 years' use of a grinder and impact wrench. Two years thereafter, multiple sclerodermic lesions appeared over the trunk, upper extremities, and thighs; these disappeared about 2 years later. Histologically, hyperplasia and nodular swelling of collagen bundles were present in the dermis. An immunological study showed the serum to be positive for anti-centromere antibody, but no visceral lesions were demonstrable. This case corresponded to generalized morphea. Case 2, a 53-year-old male, developed symptoms of vibration syndrome (Raynaud's phenomenon, numbness of both hands, impaired hearing and arthralgia) after 25 years' use of a jack hammer in a quarry. Thereafter, sclerodermic changes of the forearms, lower legs, face and abdomen occurred with an associated sclerodactyly. Histological examination of involved skin revealed diffuse hyperplasia and homogenization of collagen bundles throughout the entire thickness of the dermis. These findings, together with serum positivity for anti-RNP antibody and dilation of the lower portion of the esophagus, led us to a diagnosis of progressive systemic sclerosis. We inferred that the vibration syndrome in the present cases might be related etiologically to these forms of scleroderma.

Autoantibodies↗
PubMed1989

[Hemodynamic changes on the course of septic multiorgan failure patients].

The hemodynamic changes on the course of septic multiorgan failure (s-MOF), and the effects of norepinephrine administrated at septic shock state were evaluated in thirteen patients who died of s-MOF in ICU. The course in ICU was divided into following three stages. Stage I was for a few days after admission in ICU. Stage II was severe infected state. Stage III was the terminal state, i.e., a few days before death. Norepinephrine was administrated when conventional catecholamines (dopamine and/or dobutamine) could not maintain the blood pressure level in the shift from stage II to III, and the hemodynamic changes were evaluated before and after the administration. The following results were obtained: 1) Hemodynamic changes: The stage I was characterized as a moderately hyperdynamic state. The stage II exhibited a typical hyperdynamic state distinguished by a decrease in systemic vascular resistance (SVR). The stage III was distinguished as a normodynamic shock state, because of fall of cardiac output within normal control level. 2) Norepinephrine increased cardiac index, heart rate, and right ventricular stroke work index, but mean arterial pressure, stroke index and SVR did not exhibit any change. However, norepinephrine was useful aid to maintain the circulation in hypotensive state, when conventional catecholamines could not maintain blood pressure any more.

Adult↗
PubMed1989

[Surgical treatment of the malignant mediastinal tumors--with special reference to prosthetic reconstruction of superior vena cava].

Sixteen patients with the malignant mediastinal tumors compromising the superior vena cava (SVC) and brachiocephalic veins (BCV) were treated from April 1974 to March 1987. SVC reconstruction by prosthesis combined with or without tumor resection were performed in 6 cases and removal of the tumor with partial resection of SVC and right BCV in one case. Two patients died within one month and two patients survived over 5 years postoperatively. Tumor resection, removal of the right lung and SVC wall, and patch angioplasty were performed in one patient who died three and one half months postoperatively. Resection of the tumor and left BCV were performed in 4 patients. Segmentally resected left BCV was reconstructed with interposed graft in two, prosthesis was implanted between left BCV and right atrium in one and no venous reconstruction was attempted in one. Three patients are alive and one patient died six and one half years after operation. Exploratory mediastinotomy was carried out in 3 cases and radiation therapy alone in one case. All but one patients died within one year after diagnosis. Though the long term results of the surgical treatment for malignant mediastinal tumor was not satisfactory, extensive resection of the tumor was worth attempting, as the patency rate of the prosthetic venous reconstruction was improved.

Adolescent↗
PubMed1988

The purification and characterization of an acellular pertussis vaccine.

An acellular pertussis vaccine manufactured by Biken was investigated for purity, potency and toxicity. The vaccine was composed of almost equal proportions of pertussis toxin (PT) and filamentous hemagglutinin (FHA). The purity of the vaccine was 97-99%. The protective effects of component vaccines containing various ratios of PT and FHA were tested and it was found that the ratio of 1:1 provided the most effective vaccine.

Animals↗
PubMed1988

Development of inactivated vaccine against virus causing haemorrhagic fever with renal syndrome.

B-1 virus belonging to the hantavirus group was serially passaged in the brains of newborn mice. Inactivated vaccine was prepared from the brains after inactivation with formalin and then purification by ultracentrifugation. The antigenic potency of this vaccine in vitro was determined by antibody-bound enzyme-linked immunosorbent assay (ELISA) and serial diluted vaccine bound to an aluminium hydroxide gel was inoculated into Balb/c mice to test immunogenicity. After two injections of this vaccine preparation, antibodies were detected in the mice by immunofluorescent, neutralizing and haemagglutination inhibition antibody tests. When mice immunized with this vaccine were challenged with B-1 virus and Hantaan virus (KHF-83-61BL strain), the virus titres in their lungs and spleens were significantly less than those in non-immunized mice. These results suggest that inactivated B-1 virus vaccine is effective against virus challenge by homotypic (B-1 virus) and heterotypic (Hantaan virus) viruses.

Animals↗
PubMed1988

Lipid storage myopathy associated with recurrent Reye syndrome-like attacks, but with a normal carnitine level.

A 7-year-old girl developed recurrent episodes of hepatic and cerebral dysfunction which mimicked those in Reye syndrome (RS). Because of mild muscle weakness, she had repeated muscle biopsies which showed markedly increased amounts of lipid droplets, predominantly in type 1 fibers. Liver histological examination showed widespread hepatocellular steatosis. However, diffuse microvesicular fat, seen in RS, was not found in the cytoplasm. The concentrations of free- and acylcarnitine in serum and muscle were within normal ranges. Normal ketogenesis was induced by fasting. Based on the clinical, laboratory, and histopathological findings, our patient was initially thought to have systemic carnitine deficiency. However, the serum and muscle carnitine levels were within normal limits. Although the primary metabolic defect has yet to be elucidated, the present study indicates that lipid storage myopathy in the absence of carnitine deficiency can be complicated with RS-like episodes.

Carnitine↗
PubMed1988

Undecaprenyl diphosphate synthase from Micrococcus luteus B-P 26: essential factors for the enzymatic activity.

An undecaprenyl diphosphate synthase fraction, which was free of other prenyltransferases and was active without the addition of detergent or phospholipid, was obtained by Sephadex G-100 chromatography of cell-free extracts of Micrococcus luteus B-P 26 cells. The addition of small amounts of Triton X-100 to this fraction caused a marked loss of the enzyme activity, but the activity was gradually restored as further detergent was added. When the enzyme fraction was chromatographed on DEAE-cellulose, the synthase was partially purified, but the activity was not detected unless assayed with addition of the detergent or a lipid fraction of this bacterium. Among the three phospholipids isolated from this bacterium, cardiolipin and phosphatidylglycerol had a marked effect in activating lipid-depleted undecaprenyl diphosphate synthase, but O-lysylphosphatidylglycerol, which occurs prominently in this bacterium, had little effect.

Alkyl and Aryl Transferases↗
PubMed1988

Mechanisms of chronic recurrent idiopathic ventricular tachycardia.

In 24 patients with idiopathic ventricular tachycardia (VT), mechanisms of VT and the effects of antiarrhythmic drugs after induction were studied electrophysiologically, and by exercise testing. VT was induced electrophysiologically in 14 patients. Class 1 antiarrhythmic drugs were effective in 7 of them, which implied that one of the mechanisms of idiopathic VT was reentry related to the depressed channel dependent slow conduction. In 6 of the 14 patients, the QRS morphology of VT showed a complete RBBB with axis deviation pattern and the tachycardia was responsive to verapamil. In 2 of them, induction of VT was facilitated at low plasma verapamil concentrations. In the other 2 patients, left ventricular mapping showed that a notched potential preceding each QRS complex and the retrograde His bundle deflection with a short interval were recorded during VT. These findings suggested that the mechanism of this type of VT was reentry, mediated by Ca dependent slow conduction and located within the left bundle branch network. Exercise testing provoked VT in eight. Beta-blockers and Ca-antagonists were effective in 6 and in 4, respectively. These findings indicate the possibility that in addition to enhanced automaticity or reentry, triggered activity could play a role in the genesis of exercise related VT.

Adolescent↗
PubMed1988

Correlation between augmented resistance to influenza virus infection and histological changes in lung of mice treated with trehalose-6,6'-dimycolate.

Mice inoculated intravenously with trehalose-6,6'-dimycolate (TDM), a glycolipid component of the cell wall of Mycobacterium, in an oil-in-water emulsion (TDM emulsion) acquired a high resistance to intranasal infection by influenza virus. Athymic nude mice inoculated with TDM emulsion could not acquire such an augmented resistance to influenza virus infection. The augmented antiviral resistance of TDM emulsion-treated mice was diminished by prior intravenous inoculation of silica particles, which selectively impair macrophage functions. In vitro experiments showed that macrophage cultures treated with TDM emulsion released an activator(s) of T lymphocytes. Histological studies of the lung of TDM emulsion-inoculated mice revealed that a typical granuloma and severe perivascular lymphocyte infiltration appeared, though no such histological change was observed in the lung of control emulsion-inoculated mice. The lungs from TDM emulsion-treated athymic nude mice and the lungs from silica particle- and TDM emulsion-treated mice showed fewer and smaller granulomata and milder perivascular lymphocyte infiltration than a typical granuloma and lymphocyte infiltration in the lungs of TDM emulsion-treated mice. These and earlier results suggest that an acquired antiviral resistance of TDM emulsion-treated mice was caused by elicitation of macrophages with TDM, then activation of T lymphocytes, leading to granuloma formation and an amplified earlier interferon production in response to influenza virus infection.

Animals↗
PubMed1988

[Prostatic tissue levels of cefpiramide (CPM)].

The concentration of CPM in prostatic tissue and serum in 12 patients with benign prostatic hypertrophy was measured. One gram of CPM was injected intravenously prior to prostatectomy. One, 2, 3 and 5 hours following the administration of CPM, the mean serum level of CPM was 142, 88.2, 87.4 and 61.2 micrograms/ml, respectively, while the mean level in the prostatic tissue was 48.3, 15.1, 15.6 and 8.3 micrograms/g, respectively. The prostatic tissue level of CPM was thought to be enough to eradicate gram-negative and gram-positive bacteria in the prostate. It is presumed from our study that clinical effectiveness of CPM might be expected in the case of acute or chronic bacterial prostatitis.

Cephalosporins↗
PubMed1987

Dynamic interaction between components of hexaprenyl diphosphate synthase from Micrococcus luteus BP-26.

Hexaprenyl diphosphate synthase from Micrococcus luteus BP-26, which has been known to be dissociated into two essential components, designated as components A and B, during hydroxyapatite chromatography [Fujii, H., Koyama, T., & Ogura, K. (1982) J. Biol. Chem. 257, 14610-14612], was also resolved similarly by Sephadex G-100 or DEAE ion-exchange chromatography. Each component takes various self-aggregated forms. The apparent molecular mass of component B estimated by gel filtration on Superose 12 varied depending on its concentration, ranging from approximately 18 to 49 kilodaltons (kDa). On the other hand, the apparent molecular mass of component A varied depending on not only its concentration but also the ionic strength of the medium, ranging from approximately 13 to 24 kDa. When a mixture of components A and B preincubated in the presence of Mg2+ but in the absence of substrate was subjected to Superose 12 gel filtration, they were eluted at positions identical with those observed when they were chromatographed individually. In contrast, when a mixture of components A and B incubated in the presence of Mg2+ and substrates was filtrated on Superose 12, the elution positions were markedly changed, showing that an approximately 24-kDa aggregate of component A (designated as A) and an approximately 27-kDa aggregate of component B (designated as B) were the major species. Evidence was also obtained to show that farnesyl diphosphate (FPP) binds to the components to form an aggregate, A-B-FPP-Mg2+, which probably represents an intermediary state of enzyme catalysis.

Alkyl and Aryl Transferases↗