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Biomedical subjects

S Yamaguchi

Publications and source records attributed to S Yamaguchi.

At least 847 records · Page 47Linked to original sources

Production of infectious swine vesicular disease virus from cloned cDNA in mammalian cells.

Full-length cDNA clones of the swine vesicular disease virus (SVDV) were constructed from subgenomic cDNA clones in the expression vector pSVL (pSVLS00). The direct transfection of mammalian cells with plasmid pSVLS00 results in the production of infectious virus. The recovered virus was neutralized completely by anti-SVDV guinea-pig serum, but did show a difference in plaque morphology from the parental virus.

Animals↗

Diabetes mellitus in a young man with Bloom's syndrome.

Bloom's syndrome (BS) is a rare autosomal recessive genetic disorder in which diabetes mellitus unusually frequently develops as a complication. We report on a 21-year-old Japanese male patient with BS who exhibited impaired glucose tolerance (IGT) in the initial oral glucose tolerance test (OGTT) and had developed patterns of diabetes mellitus by the second OGTT at the 2-years-and-2-months follow-up. German and Passarge reported that the onset of diabetes in patients with BS was in late adolescence or early adulthood. Our results support the findings of German and Passarge. Therefore, when a person with BS reaches late adolescence or early adulthood, an OGTT is necessary to ascertain whether the patient has IGT or diabetes mellitus as a complication, regardless of whether or not diabetic signs such as glucosuria are present.

Adult↗

Genetic and behavioral analysis of flagellar switch mutants of Salmonella typhimurium.

At the interface between the sensory transduction system and the flagellar motor system of Salmonella typhimurium, the switch complex plays an important role in both sensory transduction and energy transduction. To examine the function of the switch complex, we isolated from 10 cheY mutants 500 pseudorevertants with a suppressor mutation in one of the three genes (fliG, fliM, and fliN) encoding the switch complex. Detailed mapping revealed that these suppressor mutations were localized to several segments of each switch gene, suggesting localization of functional sites on the switch complex. These switch mutations were introduced into the wild-type background and into a chemotaxis deletion background. Behavior of the pseudorevertants and their derivatives (1,500 strains in all) was observed by light microscopy. In the chemotaxis deletion background, about 70% of the switch mutants showed smooth swimming and the rest showed more or less tumbly swimming. There was some correlation between the mutational sites and the swimming patterns in the chemotaxis deletion background, suggesting that there is segregation of functional sites on the switch complex. The interaction of the switch complex with the chemotaxis protein, CheY, and the stochastic nature of switching in the absence of CheY are discussed.

Alleles↗

Primitive reflexes and MRI findings, cerebral blood flow in normal elderly.

We studied the relation between primitive reflexes (glabellar, snout and palmomental) and MRI findings, cerebral blood flow and mental function in 68 normal aged volunteers. One or more of the three primitive reflexes was elicited in 50% of all subjects. The subjects who had the incidental cerebral lesions showed a significantly higher incidence of the primitive reflexes than those without them. However, there was no difference in mean regional cerebral blood flow (rCBF), brain atrophy and intellectual ability between the subjects with primitive reflexes and those without. The primitive reflexes appear in a significant proportion and these reflexes have a significant relationship with incidental cerebral lesions in normal elderly.

Aged↗

Computerized tomography with longitudinal follow-up of brain atrophy in patients with Parkinson's disease.

Computerized tomographic (CT) studies with longitudinal follow-up of the relationship between supratentorial and infratentorial brain atrophy in Parkinson's disease (PD) using our new CT-derived brain atrophy index (BAI) are reported. In those patients with Parkinson's disease, CT analysis demonstrated a significant increase in brain atrophy compared with controls. Infratentorial BAI correlated significantly with supratentorial BAIs and the decrease in the infratentorial BAI correlated with a corresponding decrease in the supratentorial BAI in those with PD. It is postulated that the infratentorial brain atrophy found in patients with PD could well be secondary to supratentorial brain atrophy.

Adult↗

Molecular cloning and sequence of the complementary DNA encoding human mitochondrial acetoacetyl-coenzyme A thiolase and study of the variant enzymes in cultured fibroblasts from patients with 3-ketothiolase deficiency.

Complementary DNAs encoding the precursor of human hepatic mitochondrial acetoacetyl-CoA thiolase (T2) (EC 2.3.1.9) were cloned and sequenced. The cDNA inserts in these clones were 1,518 bases in length when overlapped, and encoded the 427-amino acid precursor of this enzyme (45,199 mol wt). This amino acid sequence included a 33-residue leader peptide moiety and a 394-amino acid subunit of the mature enzyme (41,385 mol wt). The T2 gene expression in fibroblasts from four patients with 3-ketothiolase deficiency was analyzed by Northern blotting. The T2 mRNA in all four cell lines had the same 1.7 kb as that of the control. However, the amounts of T2 mRNA differed: the content was reduced in two cell lines (cases 1 and 3), whereas it was within a normal range in others (cases 2 and 4). Pulse labeling followed by subcellular fractionation revealed that the T2 proteins in the fibroblasts from these patients are present in the mitochondria. These results suggest that different mechanisms are involved in the enzyme defects in the four patients.

Acetyl-CoA C-Acetyltransferase↗

Nonspecific lipid transfer protein (sterol carrier protein-2) defective in patients with deficient peroxisomes.

The biosynthesis and intracellular localization of nonspecific lipid transfer protein (nsLTP) in control human subjects and in patients with peroxisome-deficient disorders were investigated. The molecular mass of human nsLTP was indistinguishable from that of rat nsLTP (13 kDa) by immunoblot analysis. Intracellular localization was identical with that of catalase, a marker enzyme of peroxisomal matrix, by a double immunofluorescence study. The nsLTP was deficient in liver tissues or fibroblasts from patients with peroxisome-deficient disorders such as Zellweger syndrome and neonatal adrenoleukodystrophy (ALD). Pulse-chase experiments showed that nsLTP was synthesized as a large precursor in both the control and Zellweger fibroblasts. However, the processing to the 13 kDa mature protein was disturbed and the degradation was rapid in Zellweger fibroblasts. After somatic cell fusion using Zellweger fibroblasts from different genetic groups, the processing was normalized. These results suggest that the biosynthesis and localization of human nsLTP are similar to those of rat nsLTP and that the defect of nsLTP in peroxisome-deficient disorders is a phenomenon secondary to an abnormal transport mechanism of peroxisomal proteins. The defect of nsLTP may play an important role in metabolic disturbances in bile acid synthesis and steroidogenesis in peroxisome-deficient disorders.

Biopsy↗

Hypotensive effects on spontaneously hypertensive rats and antifungal activity on various species of Fusarium oxysporum of diethylstilbestrol-related compounds.

The diethylstilbestrol-related compounds 3,3'-dihydroxy-alpha, beta-diethyldiphenylethane (I), diethylstilbestrol (II) and hexestrol (III) showed hypotensive effects on spontaneously hypertensive rats (SHR) and antifungal activities against all Fusarium oxysporum sp. tested. As previously reported, I had strong hypotensive action on normotensive rats at the dose of 10 mg/kg, while II and III showed weak hypotensive effects on these rats at the same dose. In this work, all three compounds also had hypotensive actions on SHR at the same dose. I showed the strongest hypotensive effect (-80.0 +/- 5.0 mmHg, 10 mg/kg, i.v.) on both SHR and normotensive rats. The three compounds also had antifungal activities against five kinds of Fusarium oxysporum sp. tested. Especially, II strongly inhibited the growth of Fusarium oxysporum f. sp. raphani IFO-9972 (minimum inhibitory concentration (MIC): 1.0 micrograms/ml).

Animals↗

Biological activities of racemomycin-B, beta-lysine rich streptothricin antibiotic, the main component of Streptomyces lavendulae OP-2.

Racemomycin-B (RM-B), the main component of Streptomyces lavendulae OP-2 which is the basis of 50% of the antibiotics produced, is a streptothricin antibiotic which contains three beta-lysine moieties in the molecule. RM-B had antimicrobial activity against plant-pathogenic microorganisms and growth-inhibitory activity against the root of Brassica rapa L. at the concentration of 50 ppm. It strongly inhibited the growth of Pseudomonas syringae pv. tabaci IFO-3508 (minimum inhibitory concentration (MIC): 0.4 microgram/ml), and also showed antifungal activity against six kinds of Fusarium oxysporum species (MIC: 0.1-2.0 micrograms/ml). The antimicrobial activity of RM-B was much stronger than those of RM-A and -C which contain, respectively, one and two beta-lysine moieties in their molecules. The above activities of RM-A, -C and -B were thus in the order of -B greater than -C greater than -A: namely, the biological activity of racemomycin compounds tended to be stronger with increase in the number of beta-lysine moieties in the molecule.

Fusarium↗

[Effects of methylmercury on ethanol-induced sleeping time of mice].

This study was carried out to clarify the effects of methylmercury intoxication on the ethanol-induced sleeping time of mice. The mice were injected with methylmercury chloride (MMC) (10 mgMMC/kg body weight) subcutaneously for 1, 5 and 10 successive days (1, 5 and 10 inj.), and control mice received only saline. Twenty-four hours, after the last injection, these mice were treated with ethanol (4.5 mgEtOH/kg body weight) intraperitoneally and subsequent sleeping time was observed. After 24 hours, mice were sacrificed to measure the concentration of MMC in various brain regions and liver. A similar experiment with ethanol treatment was also performed to assay the biogenic monoamines in various brain regions and alcohol dehydrogenase (ADH) activity in liver. The results can be summarized as follows: 1) Ethanol-induced sleeping time was 170 min. in the 10 inj. and it was significantly longer than saline, 1 and 5 inj. However, other experimental groups showed no change when compared with saline. 2) Norepinephrine levels increased in white matter and pons + medulla after 1 inj. 3) Dopamine levels increased only in white matter of the 10 inj. when compared with saline. No changes were shown in the other groups. 4) Serotonin levels increased in all the regions after 1 inj. 5) ADH activity in liver did not show any alteration during the experimental period when compared with saline.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[The clinical and etiological study on juvenile periodontal disease].

Seven juvenile periodontally diseased patients were evaluated for clinical, microbiologic and local or systemic host factors. Three patients showed the localized from of periodontitis clinically and radiographically and by deep periodontal pockets associated with the molars and incisors. Four were in the generalized froms, in which in most cases all teeth were affected. The results in both diseased froms on the predominant cultivable subgingival microflora, the composition of which was not different from that in adult periodontitis, consisted of significantly increased proportions of Gram-negative anaerobic rods, Bacteroides sp. and B. gingivalis, Haemophilus sp. and H. actinomycetemcomitans were detected in 1/3 of the localized and 2/4 of the generalized periodontitis. They were of no value in distinguishing activity that enhanced disease in the generalized from. Elevated serum IgG responses were noted with B. gingivalis. No markedly functional abnormalities of neutrophils from peripheral blood have been demonstrated, however it might function with systemic factors, like an insulin-dependent diabetes. Morphologic characteristics of the oral and periodontal tissue in localized periodontitis were that the pattern of destruction was confined to specific teeth groups characterized by extensive the bucco-lingual width ratio of the dental crown to alveolar bone width. These observations indicate that the generalized form of juvenile periodontitis lesions were associated not only with the presence of subgingival bacteria, but also with conditions such as local morphologic and systemic or constitutional factors, individual variation in relation to destructive and protective aspects of the defense mechanisms.

Adolescent↗

[Ultrasonographic study on kidneys in patients with chronic renal failure. Part I. Ultrasonic measurement of renal size and analysis of renal ultrasonotomograms].

Ultrasonograms of 546 kidneys were obtained in 280 patients undergoing chronic dialysis. Dialysed kidneys could be detected in 529 of the 546 kidneys (96.9%) by ultrasonic examination. The ultrasonic diagnoses on dialysed kidneys were contracted kidney in 313 kidneys (59.2%) and acquired cystic disease of the kidney in 107 kidneys (20.2%). Ultrasonic measurement of the size of kidney (length and thickness) revealed that the kidneys in patients with chronic renal failure were much smaller than normal ones. But the kidneys in patients undergoing dialysis for more than 8 years gradually increased in size with incidence of acquired renal cysts. The kidneys in patients with diabetic nephropathy were greater in length and thickness than those with chronic glomerulonephritis. Sonographic features of dialysed kidneys were unclear renal imaging, unidentified central echoes, cortico-medulla + border and increased parenchymal echogenicity. Irregularity of the renal contour had a tendency to increase in number with incidence of cysts in long-term dialysis patients. The ultrasonograms of the kidneys with diabetic nephropathy showed fewer changes than normal ones. No major complication of the kidney was detected in the present study. However, two retroperitoneal hematomas and one renal cell carcinoma developed within two years after this examination. We believe that regular screening of the kidneys by ultrasonic examination is mandatory in patients on chronic dialysis for early diagnosis and treatment of these complications.

Adolescent↗

[Ultrasonographic study on kidneys in patients with chronic renal failure. Part II. Acquired cystic disease of the kidneys].

Ultrasonic examination of the kidney was performed on 280 patients undergoing chronic dialysis. Acquired cystic disease of the kidney (ACDK) was detected in 107 of 529 kidneys (20.2%). This paper presents an analysis of ultrasonotomograms of ACDK. Ultrasonic measurement of the size of ACDK was 72.5 +/- 15.2 mm in length and 41.7 +/- 9.8 mm in thickness. The size of ACDK was significantly greater than that of contracted kidneys by ultrasonographic diagnosis. With regard to sex distinction the length and thickness of ACDK were significantly greater in males than in females. As for laboratory data, patients with ACDK showed significantly higher values of red blood cell count, hematocrit and serum creatinine concentration compared with contracted kidneys. Prolongation of the dialysis peirod increased the incidence of ACDK. The size of ACDK showed a tendency to increase with duration of dialysis. However, no correlation was noted statistically between the incidence of ACDK and duration of dialysis and between the size of ACDK and duration of dialysis. There was a significantly lower incidence of ACDK in patients with diabetic nephropathy than those with chronic glomerulonephritis. A sonographic feature of ACDK is irregularity of the renal contour because of cystic transformation. Renal imaging, identification of the corticomedullary border, identification of the central echoes and increased parenchymal echogenicity were similar to other dialyzed kidneys. The main complications of ACDK are hemorrhage and tumor formation. We observed two retroperitoneal hematomas and one renal cell carcinoma developed within two years after this examination. The incidence of complications of ACDK was 5.1 per cent. We believe that patients with ACDK should be watched carefully by regular ultrasonic examination for early diagnosis and treatment of these complications.

Adult↗

[Adaptational changes in cone electroretinograms in man].

Changes of amplitude and implicit time of human cone electroretinogram (ERG) were studied during dark adaptation and succeeding light adaptation. Dark-adapted cone ERG was isolated by subtracting scotopic blue response from matched scotopic red response. The former represented the rod-mediated b-wave, while the latter consisted of both rod-mediated b-wave and cone-mediated b-wave or x-wave. The b-wave amplitude of dark-adapted cone ERG remained unchanged during dark adaptation, while the implicit time increased systematically, reaching a plateau. Light-adapted cone ERG was obtained by red stimulus lights under a bright background light. The amplitude of light-adapted cone ERG was markedly suppressed through dark adaptation but it recovered gradually during light adaptation, reaching the base line level. The implicit time was unchanged during light adaptation.

Adaptation, Ocular↗

[Clinical effects of oxybutynin hydrochloride (Pollakis)--especially in the treatment of pollakisuria, urgency and urinary incontinence].

The effects and the safety of oxybutynin hydrochloride were investigated in 52 patients, 17 male and 35 female, with the chief complaints of pollakisuria, urgency and urinary incontinence. Clinical responses to the drug were assessed mainly by the subjective symptoms of the patients. The diagnoses of these patients were neurogenic bladder in 17, unstable bladder in 16 and others in 19 patients. The average administration period was 66.8 days. The rate of global improvement (excellent and good) was 55% in the 2 mg dose given 3 times daily group, 68.2% in the 3 mg dose given 3 times daily group. Side effects, such as dry mouth, were observed in 2 of the 52 patients (3.8%), but no serious side effects were observed. The rate of global utility (remarkable and moderate) was 67.3%. These data indicate that oxybutynin hydrochloride seems to be useful and safe for the treatment of pollakisuria, urgency and urinary incontinence.

Administration, Oral↗