Author Fujita, Hirofumi| Shiosaka, Masahiko| Ogino, Tetsuya| Okimura, Yuya| Utsumi, Toshihiko| Sato, Eisuke F.| Akagi, Reiko| Inoue, Masayasu| Utsumi, Kozo| Sasaki, Junzo|
Published Date 2008-06-23
Publication Title Brain Research
Volume volume1206
Content Type Journal Article
JaLCDOI 10.18926/AMO/32892
FullText URL fulltext.pdf
Author Takagi, Koji| Yamada, Teruo| Miki, Yukari| Umegaki, Teruo| Nishimura, Makoto| Sasaki, Junzo|
Abstract To clarify the development of follicular growth and atresia in the immature ovary, rats. ovaries and blood were removed at fixed points during the period from 0 to 35 days after birth (Day 0 to Day 35). The ovaries were immunohistochemically examined, and blood concentrations of serum follicle-stimulating hormone (FSH) and estrogen (E) were measured. We investigated how time-course changes in follicular cell proliferation, estrogen receptor β (ERβ), apoptosis, and FSH and E concentrations are connected with follicular growth and atresia. Apoptosis was found in the ova from Day 0 to Day 3. On Day 15, apoptosis occurred in some granulosa cell nuclei in some follicles, but BrdU uptake and the presence of cyclin D2 and ER β could be observed in other granulosa cells. From Day 17, apoptosis increased in the follicular granulosa cells, and BrdU uptake and the presence of cyclin D2 and ERβ were decreased. Follicular atresia continued, reaching a peak on Day 30. Serum FSH and E concentrations increased until Day 15, then markedly decreased after Day 17. The mechanism of apoptosis in the ova from Day 0 to 3 has not been clarified. However, the onset of follicular atresia was caused by apoptotic degeneration from Days 15 to 17. These results showed that the oocytes were selected by apoptosis at 2 points in the time-course of the maturation of the ovary.
Keywords histology apoptosis proliferation estrogen follicle-stimulating hormone
Amo Type Original Article
Published Date 2007-10
Publication Title Acta Medica Okayama
Volume volume61
Issue issue5
Publisher Okayama University Medical School
Start Page 283
End Page 298
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 17971845
Web of Sience KeyUT 000250431700006
JaLCDOI 10.18926/AMO/32426
FullText URL fulltext.pdf
Author Okimasu, Eiji| Moromizato, Yasunori| Watanabe, Sadahiro| Sasaki, Junzo| Shiraishi, Noriyuki| Morimoto, Yasuko M| Miyahara, Masanobu| Utsumi, Kozo|
Abstract <p>We studied the effect of glycyrrhizin, a compound known as an anti-inflammatory and antiallergic drug, on the membrane permeability change induced by phospholipase A2 (PLA2) and on platelet aggregation. Glycyrrhizin was found to inhibit the PLA2-induced carboxyfluorescein (CF) release from D,L-dipalmitoyl phosphatidylcholine (DPPC) liposomes. Part of this inhibitory effect of glycyrrhizin on PLA2 is accounted for by the physical state of the substrate, the DPPC liposome membrane. Glycyrrhizin also inhibited collagen-induced platelet aggregation in a concentration dependent manner, which may in part account for its inhibitory effect on PLA2.</p>
Keywords phosholipase A2 glycyrrhizin liposome platelet aggregation
Amo Type Article
Published Date 1983-10
Publication Title Acta Medica Okayama
Volume volume37
Issue issue5
Publisher Okayama University Medical School
Start Page 385
End Page 391
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 6689106
Web of Sience KeyUT A1983RN98400001
JaLCDOI 10.18926/AMO/31915
FullText URL fulltext.pdf
Author Watanabe, Sadahiro| Takehara, Yoshiki| Fujii, Yoshitaka| Okimasu, Eiji| Moromizato, Yasunori| Sasaki, Junzo|
Abstract <p>To investigate the involvement of actin filaments in concanavalin A (Con A)-induced cap formation and cytochalasin B (CB)-induced zeiotic knob migration, the distribution of F-actin was studied in Con A-treated and CB-treated Ehrlich ascites tumor cells (EATC) by fluorescence microscopy using heavy meromyosin conjugated with a fluorescent dye, N-(7-dimethylamino-4-methylcoumarinyl) maleimide, (DACM-HMM). In non-treated cells, the diffuse fluorescence of DACM-HMM was observed in the cytoplasm, particularly intensely under the plasma membrane and around the nucleus. In Con A- and CB-treated cells, the fluorescence was seen at Con A-induced-capped and CB-induced-knob-accumulated regions. This fluorescence was more intense in CB-treated cells. To study the actin filaments in these fluorescent regions more clearly, the soluble components of the cells were eliminated by treatment with Triton X-100 or saponin solution containing a low concentration of glutaraldehyde, and the detergent-treated and saponin-treated cells were observed under a transmission electron microscope. Concentrated actin filaments were observed directly beneath the Con A-induced capping area and CB-induced zeiotic knob-accumulation area. The area of concentrated actin filaments appeared to correspond to the electron dense area observed in the identical region in the cells fixed without detergent treatment. More actin filaments were observed in CB-treated cells than in Con A-treated ones.</p>
Keywords DACM-HMM Ehrlich ascites tumor cells concanavalin A cytochalasin B actim capping
Amo Type Article
Published Date 1986-12
Publication Title Acta Medica Okayama
Volume volume40
Issue issue6
Publisher Okayama University Medical School
Start Page 301
End Page 311
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 3825593
Web of Sience KeyUT A1986F275800004
JaLCDOI 10.18926/AMO/31734
FullText URL fulltext.pdf
Author Moromizato, Yasunori| Watanabe, Sadahiro| Sasaki, Junzo|
Abstract <p>Concanavalin A (Con A) induced cap formation in rat ascites hepatoma cells (AH7974). In these Con A-treated cells, the association of cytoplasmic proteins with cell membranes was suggested by observing their Triton shells. The transition from G-actin to F-actin occurred in these cells. The association of membrane lipid with cytoplasmic proteins extracted from AH cells was studied by the isolation of protein-bound liposomes and phase transition release. The analysis of isolated liposomes revealed that many cytoplasmic proteins which specifically associated with liposomes were cytoskeletal elements including F-actins. The association of proteins with liposomes was affected by the lipid composition of the liposomal membrane and by the Ca2+ concentration of the incubation medium. The strong interaction of liposomal membrane with cytoplasmic proteins or isolated cytoskeletal proteins was demonstrated also by phase transition release using carboxy fluorescein-containing liposomes. These experiments showed that there was a strong affinity between lipid membrane and cytoskeletal elements including F-actins and that the amount of F-actin increased due to Con A treatment. The association of the submembranous microfilaments with the cell membrane may contribute to capping of the cells caused by Con A.</p>
Keywords concanavalin A actins liposomes phase trasition release
Amo Type Article
Published Date 1987-08
Publication Title Acta Medica Okayama
Volume volume41
Issue issue4
Publisher Okayama University Medical School
Start Page 145
End Page 154
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 3661239
Web of Sience KeyUT A1987J833200001
JaLCDOI 10.18926/AMO/31288
FullText URL fulltext.pdf
Author Sasaki, Junzo| Imanaka, Masaaki| Watanabe, Sadahiro| Otsuka, Nagayasu| Nakamoto, Shu| Mori, Masaharu|
Abstract <p>The effect of cytochalasin B (CB) on the surface structure of Ehrlich ascites tumor cells was investigated using the scanning electron microscope. The effect occurs in two steps: formation of zeiotic knobs on the cell surface and subsequent grouping of the knobs at one pole of the cell. The early step of zeiotic knob formation occurs at low concentrations of CB (0.5-1 microgram/ml) at 37 degrees C and at high concentrations of the drug (5-10 microgram/ml) at low temperature but within 1 min at 37 degrees C. This step is only partially inhibited by 5 x 10(-3) M sodium azide. The subsequent grouping of zeiotic knobs lasts for more than 2 min at 37 degrees C and occurs only in the case of high concentrations of CB. It is inhibited by sodium azide and is often associated with grouping of the microvilli, which are then lost from all of the cell surface except the area of knob-grouping.</p>
Keywords cytochalasin B Ehrlich ascites tumor cells zeiosis scanning electron microscopy.
Amo Type Article
Published Date 1981-06
Publication Title Acta Medica Okayama
Volume volume35
Issue issue3
Publisher Okayama University Medical School
Start Page 197
End Page 204
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 6457509
Web of Sience KeyUT A1981MD16600005
JaLCDOI 10.18926/AMO/31003
FullText URL fulltext.pdf
Author Nomura, Takako| Otsuka, Nagayasu| Tanaka, Yukiko| Sasaki, Junzo|
Abstract <p>A mixture of glycol methacrylate (GMA) and Quetol 523 was examined as an embedding medium for atrial tissue to be selectively stained for specific atrial granules. Semi-thin sections of rat atrial tissue embedded in this resin were stained with lead hematoxylin and observed under a light microscope. Atrial granules were found to be specifically stained blue black with lead hematoxylin. The same semithin sections stained with OsO4 vapor were examined electron microscopically and the atrial granules could be distinguised clearly from other cytoplasmic components. The GMA-Quetol 523 mixture is a useful embedding medium for studying the distribution of specific atrial granules by light and electron microscopy.</p>
Keywords specific atrial granules glycol methacrylate-Quetol lead-hematoxylin electron microscopy rat
Amo Type Article
Published Date 1988-12
Publication Title Acta Medica Okayama
Volume volume42
Issue issue6
Publisher Okayama University Medical School
Start Page 311
End Page 316
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 2467524
Web of Sience KeyUT A1988R743300002
JaLCDOI 10.18926/AMO/30996
FullText URL fulltext.pdf
Author Nomura, Takako| Kurokawa, Hideo| Kanda, Shigeto| Mizukawa, Kiminao| Sasaki, Junzo| Otsuka, Nagayasu|
Abstract <p>To clarify the mode of secretion of specific atrial granules, rat atrial muscle cells were examined by transmission electron microscopy. Atrial granule formation and exocytotic features of granules were clearly seen. Abrupt breaks in the unit membrane structure of mature granules were observed in thin sections, but these breaks were not detected in freeze-fracture replicas. These findings support the concept that the granule contents are released to the extracellular space by exocytosis.</p>
Keywords exocytosis atrial natriuretic polypeptide rat atrium electron microscopy
Amo Type Article
Published Date 1988-08
Publication Title Acta Medica Okayama
Volume volume42
Issue issue4
Publisher Okayama University Medical School
Start Page 201
End Page 206
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 3177005
Web of Sience KeyUT A1988P884600003
JaLCDOI 10.18926/AMO/30995
FullText URL fulltext.pdf
Author Sasaki, Junzo| Watanabe, Sadahiro| Nomura, Takako| Fujiwara, Tazuko| Ogura, Hajime|
Abstract <p>The cytoskeletons of two established chick embryo cell (CEC) lines were examined by fluorescence and electron microscopy and compared with those of control cells and cells transformed by Rous sarcoma virus (RSV). In normal CEC, many stress fibers were observed. On the other hand, stress fibers were disorganized in nontransformed spontaneously established CEC, non-tumorigenic CEC partially transformed with a chemical carcinogen, and tumorigenic RSV-transformed CEC. In the normal CEC, actin filaments formed several bundles along the processes of the cell. Stereo-images of the peripheral region revealed bundles of filaments which were located along the attached side to the substrate. A fine well preserved network of filaments was also observed. On the other hand, in spontaneously established, partially transformed and RSV-transformed CEC, a fine network of filaments, but no actin cables, was found. These results support previous evidence that the cytoskeletal changes themselves are not directly related to the transformation or tumorigenicity of cells. </p>
Keywords chick embryo cells cytoskeleton actin Triton X-100 Rous sarcoma virus.
Amo Type Article
Published Date 1988-08
Publication Title Acta Medica Okayama
Volume volume42
Issue issue4
Publisher Okayama University Medical School
Start Page 193
End Page 200
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 3177004
Web of Sience KeyUT A1988P884600002
JaLCDOI 10.18926/AMO/30858
FullText URL fulltext.pdf
Author Ogura, Hajime| Fujiwara, Tazuko| Watanabe, Sadahiro| Sasaki, Junzo|
Abstract <p>The effects of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) on the organization of cytoskeleton and growth of normal and established chick embryo cells (CEC) were studied. The cytoskeleton of normal CEC formed stress fibers, while that of the CEC lines established in our laboratory formed no stress fibers. TPA treatment of normal CEC resulted in disorganization of the stress fibers into amorphous structure, while that of the established CEC lines induced no reorganization of the cytoskeleton. TPA had no promotional effect in vitro or in vivo on tumor growth in normal or the established CEC.</p>
Keywords 12-O-tetradecanoyl-phorbol-13-acetate established chick embryo cell lines cytoskeleton stress fiber anchorage-independent growth
Amo Type Article
Published Date 1989-08
Publication Title Acta Medica Okayama
Volume volume43
Issue issue4
Publisher Okayama University Medical School
Start Page 249
End Page 252
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 2801188
Web of Sience KeyUT A1989AP79100008
JaLCDOI 10.18926/AMO/30673
FullText URL fulltext.pdf
Author Mori, Masaharu| Nakamoto, Shu| Kirizuka, Keizi| Sadahira, Yoshito| Awai, Michiyasu| Seno, Satimaru| Sasaki, Junzo| Utsumi, Kozo|
Abstract <p>Cytochalasin B (CB) treatment induces or accelerates the capping phenomenon in some cells. In Ehrlich ascites tumor cells (EATC) CB treatment apparently induced the capping of Con A binding sites as observed under a fluorescent microscope. However, electron microscopic examinations revealed that the CB treatment did not induce a rearrangement of Con A binding sites, but rather it only induced a change in cell shape. On the contrary, CB treatment inhibited the capping phenomenon induced by treatment with Con A. Electron microscopic observations may give exact information on the distribution of lectin binding sites.</p>
Keywords Ehrlich ascites tumor cell concanvalin A cytochalasin B cap formation
Amo Type Brief Note
Published Date 1982-12
Publication Title Acta Medica Okayama
Volume volume36
Issue issue6
Publisher Okayama University Medical School
Start Page 483
End Page 486
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 7158429
Web of Sience KeyUT A1982PW07500007
JaLCDOI 10.18926/AMO/30662
FullText URL fulltext.pdf
Author Sasaki, Junzo| Imanaka, Masaaki| Watanabe, Sadahiro| Mori, Masaharu| Nakamoto, Shu| Kirizuka, Keizi| Otsuka, Nagayasu|
Keywords cytochalasin B Ehrlich ascites tumor cells cappong zeiosis cationized ferritin
Amo Type Brief Note
Published Date 1982-08
Publication Title Acta Medica Okayama
Volume volume36
Issue issue4
Publisher Okayama University Medical School
Start Page 307
End Page 312
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 6890303
Web of Sience KeyUT A1982PE61100008
JaLCDOI 10.18926/AMO/30438
FullText URL fulltext.pdf
Author Takehara, Yoshiki| Yoshioka, Tamotsu| Sasaki, Junzo|
Abstract <p>The concentration of lipoperoxides in maternal blood increases as gestation progresses. The concentration in pregnant women at 40 weeks gestation is 1.6 times higher than in nonpregnant women. The concentration in the cord blood, however, is 70% lower than that in maternal blood. To study the role of placental tissue in the difference in the lipoperoxide concentration between the cord blood and maternal blood, we investigated the lipoperoxide concentration, antioxidant activities and in vitro lipoperoxide formation in placental tissue during pregnancy. The lipoperoxide concentration was 50% lower in placental tissue of 40 weeks gestation than in tissue of 5-11 weeks gestation. Catalase and superoxide dismutase activities in placental tissues increased as gestation progressed, while glutathione peroxidase activity and alpha-tocopherol concentration did not change significantly during the gestational period. The in vitro formation of lipoperoxides in placental tissue decreased as gestation progressed. These results show that placental tissue suppresses lipoperoxide formation in the late gestational age, lowers the concentration of lipoperoxides in the blood and protects the fetus against oxygen toxicity.</p>
Keywords lipoperoxides antioxidant factors placenta human gestation
Amo Type Article
Published Date 1990-04
Publication Title Acta Medica Okayama
Volume volume44
Issue issue2
Publisher Okayama University Medical School
Start Page 103
End Page 111
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 2363363
Web of Sience KeyUT A1990DE10000007
JaLCDOI 10.18926/AMO/30425
FullText URL fulltext.pdf
Author Fujii, Yoshitaka| Yoshioka, Tamotsu| Sasaki, Junzo|
Abstract <p>We examined the effect of fetal calf serum (FCS) on meiotic division, subsequent fertilization, and first cleavage to the 2-cell stage of rat oocytes during in vitro maturation. FCS had no effect on the nuclear progression from dictiate to metaphase of the second maturation in vitro and, FCS had no effect on the first cleavage to the 2-cell stage of fertilized oocytes. However, FCS efficiently increased penetration rate of oocytes and shortened the time required for dissolution of the zona pellucida by alpha-chymotrypsin. These results showed that FCS did not affect cytoplasmic maturation necessary for oocytes to develop to the 2-cell stages. We found that FCS only affects the zona pellucida and does not affect the nucleus or cytoplasm of rat oocytes. FCS may prevent hardening of the zona pellucida. </p>
Keywords in vitro fertilization in vitro maturation fetal calf serum rat zona pellucida
Amo Type Article
Published Date 1990-08
Publication Title Acta Medica Okayama
Volume volume44
Issue issue4
Publisher Okayama University Medical School
Start Page 203
End Page 208
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 2244475
Web of Sience KeyUT A1990DX04500004
Author Kawasaki, Shoji| Nomura, Takako| Matsuura, Junko| Sasaki, Junzo| Gao, Xian Shu| Asaumi, Jun-ichi| Nishikawa, kouji| Hiraki, Yoshio| Utsumi, Kozo|
Published Date 1995-01-31
Publication Title 岡山大学医療技術短期大学部紀要
Volume volume5
Content Type Departmental Bulletin Paper
Author 佐々木 順造|
Published Date 1975-03-31
Publication Title
Content Type Thesis or Dissertation