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M Yoshihama

Publications and source records attributed to M Yoshihama.

30 records · Page 2Linked to original sources
PubMed1996

U14 snoRNAs are encoded in introns of human ribosomal protein S13 gene.

During the mapping and sequencing of human ribosomal protein genes, we have found that U14 small nucleolar RNAs (snoRNAs) are encoded in introns of the ribosomal protein S13 gene. PCR cloning and sequencing have been employed to obtain the intron-containing (functional) human S13 gene and to eliminate a number of the processed pseudogenes. The S13 gene consists of six exons and five introns and spans a genomic region of 3.3 kb. U14 snoRNA genes are positioned in introns 3 and 5 of the S13 gene. A sequence comparison of the U14 genes in human and Xenopus laevis revealed that the regions involved in binding to 18S rRNA and the consensus (boxes C and D) of sequences for snoRNAs are highly conserved among the genes in the two species.

Base Sequence↗
PubMed1994

Physical, sexual, and emotional abuse by male intimates: experiences of women in Japan.

This article examines the nature of violence (physical, emotional, and sexual) perpetrated by Japanese men against their female intimates. Data were collected in a nationwide mail questionnaire survey with a convenience sample of 796 women between July and December, 1992. Most respondents were currently married and working full-time; average age was 43.5 years. Over three fourths reported at least one type of violence perpetrated by their male intimate partner. These Japanese women reported a wide range of abuse--from a slap to an assault with a deadly weapon, from verbal ridicules to restriction of social activities, and from incompliance with contraception to forced, violent sex. About two thirds of the most serious physically violent incidents resulted in injury. Sociocultural factors unique to Japanese women's experiences of male violence are identified and discussed along with their implications for prevention and intervention.

Adult↗
PubMed1993

Aromatase activity and the effect of estradiol and testosterone on DNA synthesis in endometrial carcinoma cell lines.

Human endometrial and breast carcinoma cell lines were examined for aromatase activity and the effects of sex steroids (estradiol and testosterone) on DNA synthesis. Aromatase activity was high (greater than 500 fmol/10(7) cells/24 h) in the cell lines MCF-7 and OMC-2, moderate (100-499 fmol/10(7) cells/24 h) in the cell lines HEC-59 and Ishikawa, and low (less than 100 fmol/10(7) cells/24 h) in the HHUA cell line. A substantial stimulation of DNA synthesis by estradiol (10(-9)M) was observed in cell lines HEC-59, OMC-2, and MCF-7, with an increase in [3H]thymidine uptake of over 250%. The Ishikawa cell line was stimulated moderately (115-249%). No estradiol-induced increase in DNA synthesis was observed in HHUA. Responsiveness of DNA synthesis to testosterone was observed in cell lines that showed the greatest response to estradiol, namely HEC-59, OMC-2, and MCF-7. Otherwise, estrogen-responsiveness did not always correlated with a significant aromatase activity. These data suggest that some but not all endometrial carcinomas may possess an aromatase-dependent growth stimulating system.

Aromatase↗
PubMed1992

Reveromycins, new inhibitors of eukaryotic cell growth. II. Biological activities.

Reveromycins A, B, C and D showed inhibitory activity against EGF-stimulated mitogen response in Balb/MK cells. Furthermore reveromycins A, C and D exhibited morphological reversion of srcts-NRK cells, antiproliferative activity against human tumor cell lines and antifungal activity. The effects of reveromycins A, C and D on eukaryotic cells were closely similar to each other, but those of reveromycin B were very weak. In vitro studies revealed that reveromycin A is a selective inhibitor of protein synthesis in eukaryotic cells.

Animals↗
PubMed1990

Inhibitory effect of a new androstenedione derivative, 14 alpha-hydroxy-4-androstene-3,6,17-trione (14 alpha-OHAT) on aromatase activity of human uterine tumors.

The development of human uterine estrogen-dependent tumors is considered to be closely related to estrogen biosynthesis. This study examined whether or not 14 alpha-hydroxy-4-androstene-3,6,17-trione (14 alpha-OHAT), a new 4-androstene-3, 17-dione derivative synthesized microbiologically, inhibits estrogen biosynthetase (aromatase) activities of human uterine tumors (i.e. uterine endometrial cancer, uterine leiomyoma and uterine adenomyosis tissues). 14 alpha-OHAT inhibited aromatase activity in all uterine tumors, dose-dependently (0.1-10 microM). Moreover, 14 alpha-OHAT did not show the binding affinity to rabbit uterine cytosol-sex steroids, and it was not converted to estrogen in human placental preparations. Thus, 14 alpha-OHAT, an aromatase inhibitor, may be useful clinically as an endocrine chemotherapy for peri- or post-menopausal women with uterine estrogen-dependent tumors.

Adult↗
PubMed1990

14 alpha-hydroxyandrost-4-ene-3,6,17-trione as a mechanical-based irreversible inhibitor of estrogen biosynthesis.

Various derivatives of androst-4-ene-3,17-dione derived from microbial transformation were evaluated as inhibitors of human placental aromatase. 14 alpha-Hydroxyandrost-4-ene-3,6,17-trione was the most potent inhibitor showing a time-dependent, pseudo-first-order inactivation of aromatase in the presence of reduced nicotinamide adenine dinucleotide phosphate with apparent Ki of 1.3 microM and Kinact of 0.23 min-1. This compound also inhibited aromatase in rat ovary and suppressed serum estradiol levels in in vivo experiments.

Androstenols↗
PubMed1985

Cloning vector system for Corynebacterium glutamicum.

A protoplast transformation system has been developed for Corynebacterium glutamicum by using a C. glutamicum-Bacillus subtilis chimeric vector. The chimera was constructed by joining a 3.0-kilobase cryptic C. glutamicum plasmid and the B. subtilis plasmid pBD10. The neomycin resistance gene on the chimera, pHY416, was expressed in C. glutamicum, although the chloramphenicol resistance gene was not. The various parameters in the transformation protocol were analyzed separately and optimized. The resulting transformation system is simple and routinely yields 10(4) transformants per microgram of plasmid DNA.

Bacillus subtilis↗
PubMedDate not supplied

Histoculture drug response assay, a possible examination system for predicting the antitumor effect of aromatase inhibitors in patients with breast cancer.

Histoculture drug response assay (HDRA) systems have been used in evaluating the cytotoxic effects of chemotherapeutic agents for many kinds of advanced cancers. We have adapted the HDRA system to estimate the antitumor effect of aromatase (estrogen synthetase) inhibitors on breast cancer. Small pieces of breast cancer tissue specimens were placed onto a collagen-matrix filled with medium containing testosterone (a substrate for aromatase) or testosterone plus an aromatase inhibitor. At the end of culture, [3H]-thymidine incorporation was measured in aliquots of the histocultured specimens after 10 days culture. The increment of thymidine incorporation in testosterone-treated specimens to that of control provides an index of existence of aromatase and estrogen-dependency, since converted estradiol from added testosterone by aromatase stimulates the incorporation. The decrease in the index of "testosterone + aromatase inhibitor"/"testosterone" indicates the antitumor effect of the aromatase inhibitor on breast cancer. Twenty-one 25 breast cancer surgical specimens were successfully cultured, and 6 showed the increased incorporation of [3H]-thymidine by testosterone. Aromatase inhibitor blocked this stimulation in these 6 specimens. These results suggested that this antitumor effect is related to the inhibition of aromatase and the aromatase inhibitor would be effective for individual patients with breast cancer which responds to testosterone in this histoculture assay system. The histoculture technique we used here is therefore expected to be useful in predicting the efficacy of aromatase inhibitors for individual patients with breast cancer.

Antineoplastic Agents↗