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S Toda

Publications and source records attributed to S Toda.

At least 109 records · Page 6Linked to original sources
PubMed1994

Isolation and classification of temperature-sensitive mutants of influenza B virus.

We isolated 25 temperature-sensitive mutants of B/Kanagawa/73 strain generated by mutagenesis with 5-fluorouracil and classified them into seven recombination groups by pair-wise crosses. All mutants showed a ratio of plaquing efficiency at the nonpermissive temperature (37.5 C) to the permissive temperature (32 C) of 10(-4) or less. At 37.5 C most of group I, II, and III mutants did not produce appreciable amounts of protein, but all other group mutants were protein synthesis-positive. A group VII mutant produced active hemagglutinin (HA) and neuraminidase (NA) at the nonpermissive temperature, but Group V mutants produced only active NA and were defective in the HA molecule. The other group mutants, including group IV mutants with mutation only in the NA gene (8, 10), lacked both activities at the nonpermissive temperature. One of nine influenza B virus isolates in 1989 had EOP 37.5/32 of 1/3 x 10(-2) and belonged to recombination group VII.

Animals↗
PubMed1994

Patients with methamphetamine psychosis admitted to a psychiatric hospital in Japan. A preliminary report.

To examine the clinical characteristics of methamphetamine (MAP) psychosis in Japan, we evaluated 104 patients with MAP psychosis (80 men and 24 women) admitted to the closed psychiatric units of Tokyo Metropolitan Matsuzawa Hospital between 1988 and 1991. There has recently been a steep increase in the number of admissions for MAP psychosis, reflecting the growth of the epidemic of MAP abuse in Japan. Although more than half of the patients were discharged within one month, 16 patients were hospitalized for more than 3 months. Most of the patients showed paranoid psychotic state similar to schizophrenia, consistent with previous reports. Despite the abstinence from MAP and antipsychotic medication, psychotic symptoms tended to persist in some of the patients. The etiological role of MAP psychosis in the development of long-lasting psychotic state was discussed.

Adolescent↗
PubMed1994

Eurystatins A and B, new prolyl endopeptidase inhibitors. III. Fermentation and controlled biosynthesis of eurystatin analogs by Streptomyces eurythermus.

Accurate and precise component analysis of eurystatin analogs in fermentation broth was devised by HPLC methods with and without 2,4-dinitrophenylhydrazonation. Detailed optimization of fermentation conditions and strain improvement by HPLC analysis significantly increased the eurystatin productivity of Streptomyces eurythermus. Chemically defined fermentation media which produced eurystatins A and B at fermentation yields comparable to complex media were elaborated for radio-isotope fermentation studies and controlled biosynthesis. Radio-isotope incorporation study using 14C-labeled amino acids in chemically defined medium demonstrated that L-leucine and L-ornithine were the direct precursors for the L-leucine and L-ornithine moieties of eurystatins A and B, respectively. Based on this finding, L-valine and L-isoleucine were supplemented to the growing culture of S. eurythermus in chemically defined medium, which resulted in the controlled biosynthesis of new eurystatin analogs named eurystatins C, D, E and F.

Amino Acids↗
PubMed1994

[A case of thymic cyst showing elevated CEA, SLX and CA125 levels in the cystic fluid associated with non-invasive thymoma].

A 66-year-old woman, who had complained of left ptosis and been diagnosed as having myasthenia gravis (ocular type) 9 years previously, was admitted to our hospital for further examination of an abnormal mass shadow on chest X-ray film. Chest computerized tomography (CT) revealed a cystic tumor in the anterior mediastinum and thoracotomy was performed to make a definitive diagnosis. The tumor could be removed completely and was diagnosed histologically as a thymic cyst with thymoma. The cyst was 32 x 30 x 28 mm in size and contained about 10 ml of brown turbid fluid. The levels of CEA (61.3 ng/ml), SLX (24,000 U/ml) and CA125 (1300 U/ml) were markedly increased in the cystic fluid, while those in serum were not elevated. Immunohistochemical staining demonstrated the epithelial cells lining the cyst to contain SLX. The findings suggest that SLX was produced in the epithelial cells of the cyst. However, neither CEA nor CA125 was positive in the epithelial cells. From our review of reported cases of thymic cyst showing elevated levels of tumor markers in the cystic fluid, the main mechanism of marked elevation of tumor markers seems to be condensation in the cystic fluid rather than increased production in epithelial cells lining the cyst. Cases of thymic cyst with thymoma are extremely rare, but our case was concluded to be incidentally associated with non-invasive thymoma.

Aged↗
PubMed1994

Efficacy of Listerine antiseptic against MRSA, Candida albicans and HIV.

The antiseptic activity of Listerine and Cool Mint Listerine against methicillin-resistant Staphylococcus aureus (MRSA), Candida albicans, human immuno deficiency virus (HIV) and oral bacteria was examined in this study. Exposure for 30 seconds to Listerine killed MRSA completely. Exposure for 30 seconds significantly decreased viable cells of C. albicans. More than 60% of HIV was inactivated by a 30 second exposure to 50% Listerine. Listerine exhibited a potent bactericidal effect against cariogenic and periodontopathic bacteria. Cool Mint Listerine had almost the same antiseptic effect against tested microorganisms. Listerine appears to be effective for killing etiologic microorganisms of opportunistic infection in the oral cavity.

Candida albicans↗
PubMed1993

Plural cells organize thyroid follicles through aggregation and linkage in collagen gel culture of porcine follicle cells.

Some follicle cells organize thyroid follicles through proliferation of single cells in collagen gel culture. The aim of this study was to clarify whether two or more (plural) cells can form follicles through aggregation and linkage in this culture system. To address this question, we performed collagen gel culture of porcine follicle cells, using cell labeling with PKH 2 dye. A mixture of dye-labeled and nonlabeled cells was cultured in collagen gel. Organized follicles consisted of both dyed and nondyed cells. This suggested that plural cells reconstructed follicles through aggregation and linkage. To further confirm this finding, cells embedded in collagen gel were cultured in inhibition of cell proliferation with 2 micrograms/ml aphidicolin. Forty to 60 percent of the cells formed follicles, which did not grow larger. Electron microscopy showed that intracytoplasmic cavities appeared in the cells. In contrast, 20-30% of the embedded cells developed into cavity-embracing single cells, which remained signet rings. These results indicate that follicle cells organize follicles in collagen gel culture by two means: through cell division of cavity-embracing single cells and through aggregation and linkage of plural cells.

Animals↗
PubMed1993

Studies on the mode of antifungal action of pradimicin antibiotics. II. D-mannopyranoside-binding site and calcium-binding site.

Based on the structure-activity relationship data of BMY-28864 and related pradimicin derivatives, the calcium salt-forming ability and the D-mannopyranoside-specific visible absorption maximum shift of BMY-28864 were analysed in the ternary complex formation of BMY-28864 with D-mannopyranoside and calcium. The free C-18 carboxyl group of BMY-28864 was proved to be the sole site for binding to calcium, while no hydroxyl groups of the aglycone were involved in calcium salt formation. The stereospecific D-mannopyranoside-recognizing ability of BMY-28864 was completely abolished by removal of the C-5 disaccharide moiety, and, more particularly, of the C-5 thomosamine moiety. Close relationship of these findings with the antifungal action was also supported by the in vitro antifungal assay and the potassium leakage induction test.

Anthracyclines↗
PubMed1993

A new neuritogenetic compound BU-4514N produced by Microtetraspora sp.

A novel neuritogenetic compound BU-4514N was isolated from the fermentation broth of Microtetraspora sp. T689-92. It showed significant NGF-mimic activity and antibacterial activity against Gram-positive bacteria. Structural studies revealed that BU-4514N was a new chemotype antibiotic related to lydicamycin.

Actinomycetales↗
PubMed1993

[A case of complete remission of metastatic skin carcinoma (erythema type) from advanced gastric cancer by CDDP administration].

A 75-year-old female with skin metastasis from advanced gastric cancer (portion A, tub2, ss beta, n2, P0H0, Borrmann 3-type) was successfully treated with CDDP at a dosage of 25 mg/body every week or two. She had undergone R2 curative subtotal gastrectomy in October 1986, and had orally taken tegafur 300 mg/day as postoperative adjuvant chemotherapy. Three years after the operation, she had skin erythema at chest and neck. A pathological examination revealed that the skin erythema was a metastasis of gastric cancer. After administration of 5-FU and MMC, the skin lesion diminished in size, but in November of 1990, it expanded again. Administration of 5-FU, MMC and epirubicin was not effective. The skin lesion expanded extensively and changed to nodular type. CDDP was intermittently administered from August 1991 to December 1991, 25 mg/body div. every week or two; the total volume of CDDP reached 225 mg. The metastatic skin carcinoma disappeared and a complete response was obtained. CEA, which had been high (190 ng/ml), regained the normal level. Thrombocytopenia and liver dysfunction developed as side effects, but reduced after cessation of CDDP administration. The patient has been well for 3 years and 6 months since the onset of the skin metastasis.

Adenocarcinoma↗
PubMed1993

Reconstruction of alveolus-like structure from alveolar type II epithelial cells in three-dimensional collagen gel matrix culture.

The purpose of this study is to reconstruct an alveolus-like structure from alveolar type II epithelial cells in a culture condition. Isolated alveolar type II epithelial cells of the rat were cultured in a three-dimensional collagen gel matrix. Single type II cells formed cellular aggregates that had a lumen after cell division in this culture condition. Through proliferation of the component cells, these aggregates grew to assume a globular or branching structure, part of which in turn developed into a large, cystic alveolus-like structure. This structure consisted of flattened epithelial cells intermingled with cuboidal epithelial cells. In these structures, the surfactant production was confirmed by immunohistochemistry and electron microscopy. To our knowledge, this is the first report of a reconstruction of an alveolus-like structure in a three-dimensional collagen gel matrix culture. This culture system seems to provide an appropriate physiological environment in which to study the differentiation and disorders of pulmonary alveoli.

Animals↗
PubMed1992

Differentiation of human thyroid follicle cells from normal subjects and Basedow's disease in three-dimensional collagen gel culture.

Thyroid follicles, an essential functional unit of the thyroid, exist in the extracellular matrix of the tissue in vivo. Therefore, in any monolayer culture system, the follicles cannot be reconstructed. Our previous study adopting three-dimensional collagen gel culture showed that isolated porcine follicle cells reconstructed thyroid follicles specific for the thyroid gland in vivo. To elucidate whether this culture system is also applicable to human follicle cells, and furthermore to provide a culture system for investigations of the pathogenesis of human thyroid diseases, we tried to culture isolated human follicle cells of normal thyroid tissue and of Basedow's disease in three-dimensional collagen gel. In this culture system, they apparently reconstructed thyroid follicles. The component cells of the reconstructed follicles exhibited structural polarity specific for human thyroid follicle cells and produced thyroid hormones. In addition, the cells responded to a TSH-stimulation in terms of morphological and functional differentiation, and they presented HLA-DR antigen with an interferon-gamma-stimulation. This report is a first instance of reconstruction of human thyroid follicles and HLA-DR antigen induction in three-dimensional follicle structures in vitro. This culture system provides a more physiological environment in vitro for biological and pathogenetic investigations of human thyroid follicle cells than the monolayer culture system. Further experiments using this method will probably provide new clues to the pathogenetic mechanisms of human thyroid diseases.

Cell Differentiation↗
PubMed1992

A unique case of extramammary Paget's disease. Derivation from eccrine porocarcinoma?

A unique case of extramammary Paget's disease is reported that may have derived from eccrine porocarcinoma. A palm-sized erythematous plaque on the patient's pubis spread to the lower abdominal wall. The center of the lesion contained a reddish tumor. Histologic findings of the erythematous plaque showed features of extra-mammary Paget's disease. Those of the reddish tumor, however, corresponded most closely to eccrine porocarcinoma, though we could not entirely rule out that the changes corresponded to larger nests of less differentiated Paget cells. The two distinct neoplastic areas showed continuity both clinically and histologically; our case differed from epidermotropic eccrine porocarcinoma in several clinicopathologic respects. Our case suggests the possibility that extramammary Paget's disease could arise from preexisting porocarcinoma.

Adenoma, Sweat Gland↗
PubMed1992

Maternal responsiveness to infants in three societies: the United States, France, and Japan.

This study examines and compares prominent characteristics of maternal responsiveness to infant activity during home-based naturalistic interactions of mother-infant dyads in New York City, Paris, and Tokyo. Both culture-general and culture-specific patterns of responsiveness emerged. For example, in all 3 locales infants behaved similarly, mothers also behaved similarly with respect to a hierarchy of response types, and mothers and infants manifest both specificity and mutual appropriateness in their interactions: Mothers responded to infants' exploration of the environment with encouragement to the environment, to infants' vocalizing nondistress with imitation, and to infants' vocalizing distress with nurturance. Differences in maternal responsiveness among cultures occurred to infant looking rather than to infant vocalizing and in mothers' emphasizing dyadic versus extradyadic loci of interaction. Universals of maternal responsiveness, potential sources of cultural variation, and implications of similarities and differences in responsiveness for child development in different cultural contexts are discussed.

Adult↗
PubMed1992

Electron microscopical and immunohistochemical studies on the induction of "Qi" employing needling manipulation.

During a sparrow-pecking and twisting-needle manipulation to the acupoints BL 23, 24 and 25 for an induction of "Qi", it was found that some transparent materials were binding to the needles after removed from the volunteer's skin. Electron-microscopical analysis of the transparent materials revealed that they corresponded to the injured fascia made up of collagen fibers, elastic fibers, fibroblasts, adipocytes and mast cells. Rarely were nerve fiber-like structures observed in the materials. Immunohistochemically, calcitonin gene-related peptide-positive nerve fibers could be demonstrated in the acupoint BL 24 associated fascia. A possible functional relationship between the needle manipulation and the induction of Qi-sensation is discussed along with the acupoint tissue constitution.

Acupuncture Points↗