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| Registros recuperados: 77 | |
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| HAYASHI, Ken-Go; BERISHA, Bajram; MATSUI, Motozumi; SCHAMS, Dieter; MIYAMOTO, Akio; 松井, 基純; 宮本, 明夫. |
| Recent findings indicate that the changing profile of angiopoietins (ANPT) and their receptor Tie2 are closely associated with development and regression of the vascular network in the cyclic ovary. We previously reported that mRNA expression for the ANPT-Tie system in theca interna changes during bovine follicular development and atresia, and both ANPTs affect steroidogenesis in the preovulatory follicle. The aim of this study was to investigate mRNA expression for ANPT1, ANPT-2 and Tie2 in granulosa cells (GC) during follicular development in the cow. Bovine follicles were classified according to the estradiol-17β (E2) concentration in follicular fluid (FF) as follows: (1) E2<0.5, (2) 0.5<E2<5, (3) 5<E2<20, (4) 20<E2<180 and (5)... |
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Palavras-chave: Follicular development; Angiopoietin-Tie system; Granulosa cell; Cow. |
| Ano: 2004 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2975 |
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| SHIMIZU, Takashi; AKIYAMA, Hirotada; ABE, Yasuyuki; SASADA, Hiroshi; SATO, Eimei; MIYAMOTO, Akio; UCHIDA, Takafumi; 清水, 隆; 宮本, 明夫. |
| Protein phosphorylation on certain serine or threonine residues preceding proline (Ser/Thr-Pro) is a pivotal signaling mechanism in diverse cellular processes. Pin1 is a highly conserved enzyme that isomerizes only the phosphorylated Ser/Thr-Pro bonds in certain proteins, thereby inducing conformational changes. Although much protein is phosphorylated in the ovary, the role of Pin1 in the ovary is still unknown. The purpose of this study is to investigate the effects of gonadotropins on protein and mRNA expression of Pin1 in mice ovaries. Quantitative PCR analysis showed that the expression of Pin1 mRNA significantly increased in the ovaries of equine chorionic gonadotropin (eCG)-treated mice compared with those of untreated mice (P<0.05). However,... |
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Palavras-chave: E2F; Follicle development; Gonadotropin; Ovary; Pin1. |
| Ano: 2006 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4056 |
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| TETSUKA, Masafumi; NISHIMOTO, Hiromi; MIYAMOTO, Akio; OKUDA, Kiyoshi; HAMANO, Seizo; 手塚, 雅文; 宮本, 明夫. |
| Glucocorticoids modulate ovarian function in cattle. However, their regulatory mechanisms have not been fully elucidated. In the present study, we examined gene expression of two glucocorticoid-metabolizing enzymes, a bidirectional 11β-HSD type 1 (11HSD1) and a dehydrogenase 11β-HSD type 2 (11HSD2), and glucocorticoid receptor (GR) in bovine follicles during follicular maturation and atresia. Granulosa cells (GCs) and theca interna layers (TIs) were harvested from follicles classified as small growing, dominant, preovulatory, early atretic and late atretic follicles. The expression levels of 11HSD1, 11HSD2 and GR mRNA were quantified by real-time PCR. In the healthy follicles, expression of 11HSD1 mRNA increased as follicles matured, both in GCs and TIs. A... |
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Palavras-chave: Bovine; Cortisol; 11β-HSD; Follicle; Glucocorticoid receptor; MRNA. |
| Ano: 2010 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2810 |
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| MAGATA, Fumie; SHIRASUNA, Koumei; STRÜVE, Klaas; HERZOG, Kathrin; SHIMIZU, Takashi; BOLLWEIN, Heinrich; MIYAMOTO, Akio; 清水, 隆; 宮本, 明夫. |
| Persistence of the corpus luteum (CL) in cattle usually occurs during the puerperium and is associated with interference of prostaglandin (PG) F2α release from the uterus. The objective of the present study was to determine for the first time the gene expressions in the persistent CL compared with the CL of pregnancy and cyclic CL. Three types of CL biopsy samples were collected from 32 lactating Holstein cows: (1) CL persisting for 29 to 33 days after the first ovulation postpartum (persistent CL, n=9), (2) CL between days 29 and 33 of early pregnancy (CL of pregnancy, n=8) and (3) CL between days 10 and 13 of the estrous cycle (cyclic CL, n=27). mRNA expression of 2',5'-oligoadenylate synthetase-1 was upregulated only in the CL of pregnancy, confirming... |
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Palavras-chave: Dairy cow; Early pregnancy; Persistent corpus luteum; MRNA expression. |
| Ano: 2012 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3938 |
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| Ozawa, Takahiro; Acosta, Tomas J.; Nakamura, Tadashi; Miyamoto, Akio; 中村, 正; 宮本, 明夫. |
| The presence of gonadotropin-releasing hormone (GnRH)-like protein has been previously demonstrated in the bovine follicle. This GnRH-like protein was purified and concluded to be histone H2A. However, neither GnRH peptide nor specific GnRH-immunoreactivity (GnRH-IR) has been demonstrated in the bovine follicle so far. Thus, this study focused on the detection of specific GnRH-IR using the second-antibody enzyme immunoassay in isolated bovine mature follicles, and on an examination of the direct effect of luteinizing hormone (LH), endothelin-1 (ET-1), and cytokines on the GnRH-IR using an in vitro microdialysis system (MDS). We further examined a cross-reactivity of the GnRH antibody with bovine histone H2A. GnRH-IR was detected in microdialyzed perfusate... |
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Palavras-chave: GnRH; Immunoreactivity; Microdialysis; Follicle; Cow. |
| Ano: 2000 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2970 |
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| ACOSTA, Tomas J.; TETSUKA, Masa; MATSUI, Motozumi; SHIMIZU, Takashi; BERISHA, Bajram; SCHAMS, Dieter; MIYAMOTO, Akio; 松井, 基純; 清水, 隆; 宮本, 明夫. |
| The aim of the present in vivo study was to monitor real-time fluctuations of cortisol (Cr) in the wall of preovulatory follicles using a microdialysis system (MDS) implanted in the theca layer as well as changes in ovarian venous plasma (OVP) and jugular venous plasma (JVP). Seven cows were superovulated using FSH and prostaglandin F2α injections. Dialysis capillary membranes were surgically implanted into the theca layer of mature follicles and connected to a microdialysis system. Fractions of the perfusates were collected from Day -1 (Day 0=LH surge) to Day 3. No difference in the concentrations of Cr between JVP and OVP was detected throughout the experiment. Circulating concentrations of Cr ranged from 20 to 35 ng/ml 8 h after surgery in ovulatory and... |
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Palavras-chave: Bovine; Cortisol; Follicle; Ovary; Ovulation. |
| Ano: 2005 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2980 |
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| KAWASHIMA, Chiho; ITO, Nozomi; NAGASHIMA, Shuntarou; MATSUI, Motozumi; SAWADA, Kumiko; SCHWEIGERT, Florian J.; MIYAMOTO, Akio; KIDA, Katsuya; 川島, 千帆; 松井, 基純; 宮本, 明夫; 木田, 克弥. |
| The aim of the present study was to investigate nutritional and metabolic parameters during the dry and early postpartum periods of ovulatory and anovulatory cows, as well as their postpartum reproductive performance. Blood samples from 20 multiparous Holstein cows were collected once a week from the far-off dry period to 3 weeks postpartum. Early postpartum (0–3 weeks) ovulation was confirmed using plasma progesterone concentration profiles, and cows were considered ovulatory if they had resumed luteal activity by this point (n = 9), whereas cows that had not were considered anovulatory (n = 11). Data from the ovulatory and anovulatory cows were analyzed separately for the far-off dry period (7–4 weeks prepartum), the close-up dry period (3–1 weeks... |
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Palavras-chave: Dairy cow; First ovulation; Hepatic enzyme; Liver function; Reproductive performance. |
| Ano: 2016 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4308 |
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| KOBAYASHI, Shu-ichi; ACOSTA, Tomas J.; HAYASHI, Kanako; BERISHA, Bajram; OZAWA, Takahiro; OHTANI, Masayuki; SCHAMS, Dieter; MIYAMOTO, Akio; 宮本, 明夫. |
| It is well known that prostaglandin (PG) F2α and PGE2 are actively produced by bovine early corpus luteum (CL) at higher levels than in the CL of later stages. However, there is no in vivo information about the local secretion of PGs within bovine developing CL so far. Thus, the objective of the present study was to determine in detail the real-time changes in PGF2α and PGE2 secretion within developing CL. A microdialysis system (MDS) was surgically implanted into the newly formed CL of 6 cows on Day 3 after GnRH administration (about 1.5 days after ovulation) to induce superovulation following FSH treatment. Both PGF2α and PGE2 release were high during the first 24 h within developing CL but decreased thereafter. These profiles were well reflected in the... |
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Palavras-chave: PGF2α; PGE2; Developing CL; Cow; In vivo. |
| Ano: 2002 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2974 |
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| MAGATA, Fumie; HORIUCHI, Maya; MIYAMOTO, Akio; SHIMIZU, Takashi; 宮本, 明夫; 清水, 隆. |
| In postpartum dairy cows, lipopolysaccharide (LPS) derived from gram-negative bacteria such as Escherichia coli causes uterine inflammation and leads to ovarian dysfunction. The aim of this study was to determine the effect of LPS on steroid production in bovine theca cells at different stages of follicular development. Theca cells isolated from pre- and post-selection follicles (PRFs, <8.5 mm in diameter, and POFs, >8.5 mm in diameter, respectively) of bovine ovaries were exposed to LPS under luteinizing hormone (LH) conditions, estradiol (E2) conditions or both conditions in vitro. Bovine theca cells expressed the LPS receptor gene complex: Toll-like receptor 4 (TLR4), CD14 and MD2. LPS suppressed progesterone (P4) and androstenedione (A4)... |
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Palavras-chave: Androstenedione; Dairy cow; Lipopolysaccharide; Progesterone; Theca cells. |
| Ano: 2014 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3935 |
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| NOZAKI, Hirofumi; WIJAYAGUNAWARDANE, Missaka P.B.; KODITUWAKKU, Suranga P.; YOSHIDA, Takashi; NAKAMURA, Tadashi; ARAI, Ikichi; URASHIMA, Tadasu; MIYAMOTO, Akio; 中村, 正; 浦島, 匡; 宮本, 明夫. |
| N-acetylglucosaminyltransferase I (GnT I; EC 2.4.1.101), which catalyzes the first step in the conversion of oligomannose to complex or hybrid N-glycans of glycoproteins, was found in media cultured with bovine oviduct epithelial cells (BOEC) obtained from non-pregnant cows during the follicular phase. Combined treatment with specific hormones increased GnT I release from BOEC. Luteinizing hormone (LH; 10 ng/ml) alone slightly, but together with 17β-estradiol (E2; 1 ng/ml), synergistically increased GnT I activity. Vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF) α, which have been shown to have their highest activities in the bovine oviduct during the periovulatory period, also increased in GnT I activity. This study provides the... |
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Palavras-chave: Bovine; Luteinizing hormone (LH); N-acetylglucosaminyltransferase I; Oviduct; Tumor necrosis factor (TNF) α; Vascular endothelial growth factor (VEGF). |
| Ano: 2005 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2978 |
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| KAWASHIMA, Chiho; MATSUI, Motozumi; SHIMIZU, Takashi; KIDA, Katsuya; MIYAMOTO, Akio; 川島, 千帆; 松井, 基純; 清水, 隆; 木田, 克弥; 宮本, 明夫. |
| During recent decades, milk production per cow has increased drastically due to improved management, nutrition, and genetic selection; however, the reproductive performance of high-producing dairy cows has been declining. One of the factors responsible for this low reproductive performance is negative energy balance (NEB). NEB affects the onset of first ovulation in early postpartum cows. It is generally accepted that early first ovulation positively relates to the resumption of normal ovarian function, first service, and conception rate in dairy cows. Hence, delayed first ovulation has a negative impact on subsequent fertility. The metabolic condition of cows in NEB shifts to catabolic metabolism, which in turn causes increased plasma growth hormone and... |
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Palavras-chave: Β-Carotene; Dairy cow; First follicular wave postpartum; First ovulation; Metabolic hormone. |
| Ano: 2012 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4041 |
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| SHIRASUNA, Koumei; SASAHARA, Kiemi; MATSUI, Motozumi; SHIMIZU, Takashi; MIYAMOTO, Akio; 白砂, 孔明; 松井, 基純; 清水, 隆; 宮本, 明夫. |
| Administration of prostaglandin (PG) F2α in cattle during the mid-luteal phase (Days 8-12 of the estrous cycle) drastically reduces the plasma progesterone concentrations and the volume of the corpus luteum (CL). However, PGF2α does not induce luteolysis during the early luteal phase (up to Day 5 of the estrous cycle). To characterize the possible distinct difference in acute response to a luteolytic dose of PGF2α administration, we determined various mRNA expressions in the early and mid CL relating to angiogenesis, vasoactivation and PG-related factors at 30 min after PGF2α injection in cyclic cows. The experiments were conducted on Day 4 (early CL) and Days 10-12 (mid CL). Cows were either injected with 500 μg PGF2α analogue or saline as the control... |
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Palavras-chave: Corpus luteum; Cow; Luteolysis; Prostaglandin F2α. |
| Ano: 2010 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2812 |
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| KOBAYASHI, Shu-ichi; MIYAMOTO, Akio; 宮本, 明夫. |
| Luteal cells utilize lipoproteins (LIPs) for progesterone (P) synthesis. A luteolysin prostaglandin F2α (PGF 2α) has shown to prevent the LIPs utilization for steroidogenesis in bovine midcycle luteal cells. However, a luteolytic injection of PGF2α before Day 5 (Day 0=estrus) can not induce the regression of the corpus luteum (CL). This suggests that the intraluteal mechanism of PGF2 α action on the LIPs utilization in early CL is different from that of the mid luteal stage. Thus, this study aimed to investigate the interaction between PGF2 α and LIPs on the secretion of P and oxytocin (OT) from bovine early CL. An in vitro microdialysis system (MDS) was used as a model. Each bovine early CL (Days 3-4) was implanted with the MDS, and maintained in an organ... |
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Palavras-chave: PGF2α; Lipoproteins; Early CL; Cow. |
| Ano: 2000 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2972 |
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| KOWSAR, Rasoul; HAMBRUCH, Nina; LIU, Jinghui; SHIMIZU, Takashi; PFARRER, Christiane; MIYAMOTO, Akio; 清水, 隆; 宮本, 明夫. |
| This study aimed to investigate the role of epithelial cells in regulating innate immunity in bovine oviduct epithelial cell (BOEC) culture. We studied the effect of Escherichia coli lipopolysaccharide (LPS) and its interaction with ovarian steroids, estradiol (E2) and progesterone (P4), and luteinizing hormone (LH) at concentrations observed during the preovulatory period on immune responses in BOEC culture. Immunohistochemistry of oviduct tissue showed intensive expression of Toll-like receptor-4 (TLR-4) and TLR-2 in epithelial cells. A dose of 10 ng/ml LPS stimulated TLR-4, cyclooxygenase-2 (COX-2), nuclear factor kappa B inhibitor A (NFKBIA), interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) expression, indicating an early pro-inflammatory... |
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Palavras-chave: Bovine oviduct epithelial cell; Ovarian steroids; TLR-4; Th1/Th2 response. |
| Ano: 2013 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3937 |
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| Kawashima, Chiho; Fukihara, Saori; Maeda, Mayumi; Kaneko, Etsushi; Montoya, Carlos Amaya; Matsui, Motozumi; Shimizu, Takashi; Matsunaga, Nobuyoshi; Kida, Katsuya; Miyake, Yoichi; Schams, Dieter; Miyamoto, Akio; 川島, 千帆; 松井, 基純; 清水, 隆; 木田, 克弥; 三宅, 陽一; 宮本, 明夫. |
| Recent studies suggest that IGF-I is a crucial regulatory factor in follicular growth during early post-partum period. The aim of the present study was to determine in detail the changing profiles of metabolic and reproductive hormones in relation to ovulation of the dominant follicle (DF) of the first follicular wave post-partum in high-producing dairy cows. Plasma concentrations of related hormones in 22 multiparous Holstein cows were measured from 4 weeks pre-partum to 3 weeks post-partum, and the development of DF was observed with colour Doppler ultrasound. Thirteen cows showed ovulation by 15.2 days post-partum. Anovulatory cows showed higher GH and lower IGF-I levels than those in ovulatory cows during the peri-partum period. Each DF developed... |
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Palavras-chave: GROWTH-FACTOR-I; COMPETITIVE ENZYME-IMMUNOASSAY; ENERGY-BALANCE; OVARIAN ACTIVITY; STIMULATING-HORMONE; ESTRADIOL PRODUCTION; BODY CONDITION; MESSENGER-RNA; HOLSTEIN COWS; IGF-I. |
| Ano: 2007 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/1658 |
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| ISHII, Mitsuo; KOBAYASHI, Syuichi; ACOSTA, Tomas J.; MIKI, Wataru; YAMANOI, Takahiro; MATSUI, Motozumi; MIYAKE, Yoh-Ichi; MIYAMOTO, Akio; 石井, 三都夫; 松井, 基純; 三宅, 陽一; 宮本, 明夫. |
| The aim of this study was to clarify the relationship between circulating oxytocin (OT) and PGF2α metabolite (PGFM) in mares at the third stage of labor and placental expulsion time in order to investigate a cause of retained placenta of which the incidence increase in a heavy draft mare. Blood was sampled every 5 min from foaling to expulsion of the placenta in 18 heavy draft mares to evaluate circulating OT and PGFM. The relationships between OT and PGFM concentration and recorded placental expulsion times were investigated. The results were as follows (1) The highest level of OT concentration was observed close to foaling in 15 mares. (2) The OT concentrations close to foaling were variable with a large difference from the lowest concentration, 22.1... |
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Palavras-chave: Heavy draft mare; Oxytocin; 15-keto-dihydro prostaglandin F2α (PGFM); Placental expulsion. |
| Ano: 2008 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3089 |
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| Registros recuperados: 77 | |
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