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Biomedical subjects

A Yoshida

Publications and source records attributed to A Yoshida.

At least 919 records · Page 51Linked to original sources
PubMed1987

Inhibition of Streptococcus mutans glucosyltransferase by M-GTFI, a new inhibitor.

Two hundred strains of soil microorganisms were screened for the production of inhibitors of the glucosyltransferase activity of Streptococcus mutans strain, K1-R. The strain producing the greatest amount of inhibitor was one recently isolated in our laboratory. It has now been identified as a strain of Micromonospora narashinoensis on the basis of morphological and physiological studies. The inhibitor, M-GTFI, affects the glucosyltransferase that produces the water-insoluble glucan rather than that which produces the water-soluble glucan. Fuchsin-sulphite staining of the inhibitor after its purification by polyacrylamide gel electrophoresis indicates that it is probably an acidic substance. It had Mr 5700 as was determined by gel filtration. From an examination of the effects of this inhibitor on representative strains of S. mutans other than K1-R, there is a suggestion of a similar selectivity for the water-insoluble glucan-forming activity in other strains.

Dental Caries↗
PubMed1987

Low-dose irradiation to head, neck, or chest during infancy as a possible cause of thyroid carcinoma in teen-agers: a matched case-control study.

A matched case-control study was performed to identify the etiologic factors for thyroid carcinoma in teen-agers. Twenty-seven cases and 69 controls were investigated to assess the significance of various maternal and subject factors. Irradiation during infancy was the only factor which showed a statistically significant association with the incidence of thyroid cancer in teen-agers (summary X2 = 8.040; d.f. = 1; P less than 0.005). The estimated dose ranged from 0.2 to 40 rads on the head, neck, or chest during infancy.

Female↗
PubMed1987

Risks for malignancies in patients with chronic thyroiditis: a long-term follow-up study.

As a typical autoimmune disease, chronic thyroiditis may impose unusual risks for malignancies. A long-term follow-up study of a large number of patients (4,531) with chronic thyroiditis at the Noguchi Hospital in Ooita Prefecture was conducted for 0-24 years, the objective being to assess risks for various sites of neoplasms by comparing the observed numbers of deaths with the expected numbers computed from the mortality rates in Japan. There was no increase in risk for overall malignancies (90 observed vs. 104.1 expected) or breast cancer (4 observed vs. 5.7 expected). The patients had an increased risk for myelo- and lympho-proliferative neoplasms (13 observed vs. 4.9 expected, P less than 0.01), as found in a few previous follow-up studies. A new and unexpected finding was that the patients showed decreased risk for cancers of digestive tract (24 observed vs. 44.3 expected, P less than 0.01). The reason for this decline could not be elucidated in this study, so that further epidemiological studies and animal experiments in this respect are needed.

Adolescent↗
PubMed1987

[Preeclampsia and tubular dysfunction].

Renal involvement associated with preeclampsia is well investigated, especially from the aspect of glomerular lesion and coagulation. On the other hand, only a few studies on tubular dysfunction during normal pregnancy and preeclampsia have been reported. The first study was carried out to clarify and estimate the chronological changes in tubular function. Pregnant women without obvious tubular dysfunction and toxemia (group A) were investigated using serum Cl, Na minus Cl (Na-Cl index), uric acid and urinary beta 2-microglobulin (u-beta-MG) at the 10th, 20th, 30th and 36th weeks of gestation. The second study was carried out to determine the significance of tubular dysfunction accompanied by preeclampsia. Patients with severe preeclampsia (group B) and normal pregnancy (group C) were examined by the same index of tubular dysfunction. The diagnosis of severe preeclampsia was confirmed with hypertension (over 170/110 mmHg), proteinuria (beyond 3 g/day) and severe edema. The following results were obtained: Urinary beta-MG and serum Cl increased during the third trimester in group A, but the Na-Cl index decreased. The serum uric acid concentration increased during the third trimester in group A. Tubular dysfunction was evident during the third trimester in normal pregnancy. Every index of tubular dysfunction including u-beta-MG, serum Cl, Na-Cl index and uric acid in group B was significantly higher than in group C. In group B, 4 fetuses died and 7 out of 15 cases required Cesarean sections. The critical line of tubular dysfunction for fetal prognosis was Cl 110 mEq/l, Na-Cl index 28 mEq/l, uric acid 6.0 mg/dl and u-beta-MG 1,000 micrograms/l.(ABSTRACT TRUNCATED AT 250 WORDS)

Chlorine↗
PubMed1987

Glucose-6-phosphate dehydrogenase of malaria parasite Plasmodium falciparum.

Plasmodium falciparum growth is impaired in glucose-6-phosphate dehydrogenase (G6PD)-deficient red blood cells (RBCs), and malaria has been implicated in the spreading of deficient variants in malaria-endemic areas. Recent reports suggest that the malaria parasite can adapt itself to grow in these variant RBCs by producing its own G6PD, but studies on parasite G6PD are very limited. In this report, we define the properties of the parasite G6PD. G6PD was partially purified from infected and uninfected variant RBCs associated with severe G6PD deficiency. G6PD from infected RBCs contained two components separable by starch gel electrophoresis: a major component (approximately 90% activity) with a very slow anodal electrophoretic mobility and a minor component (approximately 10% activity) with the same mobility as the host G6PD. Parasite G6PD exhibited much higher affinity (low Km) to G6P and nicotinamide-adenine dinucleotide phosphate (NADP) than did human G6PD. Southern blot hybridization indicated that the parasite genome contained nucleotide sequences that were hybridizable with the human G6PD cDNA. These data indicate that the parasite is capable of adapting to G6PD-deficient RBCs by producing its own G6PD.

Collodion↗
PubMed1987

Quantitative analysis of inner ear anomalies by high resolution CT scanning of the temporal bone.

High resolution CT-scanning of the temporal bone revealed malformations of the labyrinthine capsule in 50 ears in our clinic from November 1980, to the end of 1984. Detailed assessment of the nature and extent of the abnormality allowed each ear to be awarded a mathematical score. Using statistical methods, the score was then correlated with the patient's hearing in that ear. By this method it was possible, with an 80% chance of being correct, to allocate a patient into one of two groups, i.e. partial deafness or total deafness.

Adolescent↗
PubMed1987

[Clinical evaluation of cefuzonam in children].

Cefuzonam (L-105, CZON), a new parenteral cephalosporin, was evaluated for its efficacy and safety in 22 children with bacterial infections (Table 1). The results obtained are summarized below. MICs of CZON to 26 strains of isolated organisms are shown in Table 2. MICs to all 14 strains of Haemophilus influenzae and 6 strains of Streptococcus pneumoniae were less than 0.05 microgram/ml. The MIC to 2 strains of Staphylococcus aureus was 0.39 microgram/ml and that to another was 0.78 microgram/ml. Two strains of Escherichia coli showed MICs of less than 0.05 and 0.10 microgram/ml, respectively. The MIC to 1 strain of Enterococcus faecalis was 6.25 micrograms/ml. The CZON was administered in 3 or 4 divided doses at a daily dosage ranging from 58.5 to 85.7 mg/kg by 30-minute drip infusion or intravenous injection to 22 patients (9 cases of pneumonia, 9 cases of tonsillitis, 2 cases of bronchitis, 1 case each of suppurative parotitis and acute pyelonephritis) and the following clinical results were obtained; excellent: 12 cases; good: 7 cases; fair: 3 cases. The overall efficacy rate was 86% (Table 4). Diarrhea was observed in four patients, and was resolved with or without discontinuation of the medication within a week. Anemia was noted in 2 cases. Leucopenia and neutropenia was observed in 1 case. There were a moderate rises in S-GOT and S-GPT activities in 1 patient (Table 4), and they necessitated the cessation of the CZON therapy. The S-GOT and S-GPT activities became normal after the drug treatment was stopped.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1987

Direct detection of usual and atypical alleles on the human aldehyde dehydrogenase-2 (ALDH2) locus.

A method for determining human mitochondrial aldehyde dehydrogenase (ALDH2) genotypes was developed. Two 21-base synthetic oligonucleotides, one complementary to the usual ALDH2(1) gene and the other complementary to the atypical ALDH2(2) gene, were used as specific probes for in-gel hybridization analysis of human genomic DNA from either peripheral blood cells or livers. Under appropriate hybridization conditions, these two probes can hybridize to their specific complementary alleles and thus allow the genotyping of the ALDH2 locus.

Aldehyde Dehydrogenase↗
PubMed1986

mRNA for the three human alcohol dehydrogenase subunits: size heterogeneity and developmental changes.

Human alcohol dehydrogenase consists of three types of subunits (alpha, beta, and gamma) which are governed by three separate loci. mRNA components for the three subunits were examined by Northern blot hybridization, using a common cDNA probe and specific oligonucleotide probes. A marked size heterogeneity of beta mRNA, ranging from 1.6 kb to 5.2 kb (of which the 2.4-kb and 3.5-kb were major), was observed in the adult liver. The mRNA for the gamma subunit was homogeneous (about 1.6 kb), and that for the alpha subunit contained a major 1.6-kb and a minor 4.3-kb component. The amount of mRNA was much lower (approximately 10% of adult) and the mRNA was less heterogeneous in the infant liver; i.e., an alpha mRNA (1.6 kb) and two beta mRNAs (a major 1.6 kb and a minor 3.5 kb), and no detectable gamma mRNA. The short beta mRNA, with 1.6 kb, could not be hybridized with a non-coding cDNA fragment that originated from the 3'-end of the 2.6 kb beta cDNA. The observed multiple ADH mRNAs, with a common coding region and different 3'-untranslated regions, are generated by utilization of multiple polyadenylation signals. The selection of polyadenylation signals and the rate of transcription of the three ADH loci are developmentally regulated. The 4.3-kb-long mRNA, which was hybridized with both a- and beta-specific probes, could be related to the previously cloned "fused beta-alpha" cDNA.

Adult↗