Pituitary Response to Exogenous GnRH on Day 7 Postpartum in High-producing Dairy Cows     

T. Osawa  T. Nakao  K. Nakada  M. Moriyoshi  K. Kawata 《Reproduction in domestic animals》1996,31(2):343-347

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Localization of inhibin alpha-, betaA- and betaB-subunits and aromatase in ovarian follicles with granulosa theca cell tumor (GTCT) in 6 mares     

Hoque S  Derar RI  Senba H  Osawa T  Kano K  Taya K  Miyake Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(6):713-717

To clarify the morphological and immunohistochemical characteristics in mares with granulosa theca cell tumor (GTCT), the localization of inhibin subunits (alpha, betaA, betaB) and aromatase in the granulosa cell layers and theca layers in the ovarian follicles were determined by immunohistochemical staining. The follicles were obtained from the ovaries of 6 mares with GTCT and 4 normal mares as controls. Immunohistochemically, inhibin alpha-subunit was localized in the granulosa cells of all follicles showing different sizes in all GTCT cases and betaA- subunit was localized in two GTCT cases in all sized follicles. But inhibin betaB- subunit and aromatase were not localized in GTCT cases. On the other hand, inhibin alpha-, betaA-, and betaB-subunits and aromatase were localized in the large and medium sized follicles, but inhibin betaA- and betaB-subunits and aromatase were not stained in the small sized follicles in normal cases. These findings suggest that some mares with GTCT can secrete dimeric inhibin (inhibin A), but all GTCT cases cannot secrete inhibin B. By the results of aromatase staining it is clear that testosterone is not converted into estradiol due to the lack of aromatase in the GTCT follicles.  相似文献   

Age and growth of alfonsino Beryx splendens from the Kanto District, central Japan, based on growth increments on otoliths     

Toru  TANIUCHI  Takayuki  KANAYA  Shuuichi  UWABE  Takahito  KOJIMA  Seiji  AKIMOTO  Isamu  MITANI 《Fisheries Science》2004,70(5):845-851

ABSTRACT:   Age and growth of alfonsino Beryx splendens (Lowe) were studied using counts of presumed daily incremental growth rings on the transverse section of otoliths of fish collected from the Kanto District, central Japan. Microstructural growth increments were observed from the core to the outermost margin of the broadest of approximately 50 branches formed on the surface of an otolith. Of 98 otoliths examined, 46 were readable. The number of increments and fish lengths ranged from 448 (218 mm fork length [FL]) to 3701 (411 mm FL). The ages of these fish were estimated to be 1 year, 2 months and 10 years, 2 months, respectively, assuming that an increment was formed daily. The von Bertalanffy growth equation combined for males and females was expressed as follows: L _t  = 542 {1 −  exp  [−0.133( t  + 2.00)]}, where L _t is fork length (mm) at yearly age t . The results of the present study were compared with those of other researchers who had studied alfonsino from central Japan.  相似文献   

Quantification and Understanding of Above and Belowground Biomass in Medium Saline Zone of the Sundarbans,Bangladesh: The Relationships with Forest Attributes     

Md. Salim Azad  Md. Kamruzzaman  Akira Osawa 《Journal of Sustainable Forestry》2020,39(4):331-345

ABSTRACT

The relationship between stand attributes and biomass accumulation pattern in a mangrove forest has been intensively studied in this study. We assessed above (AGM) and belowground mass (BGM) and examined the relationship between forest attributes and aboveground mass in the Sundarbans, Bangladesh. The study was conducted with 18 plots having total area of 1.08 ha. The mean AGM and BGM of the study sites were 234.08 and 132.85 Mg ha^?1 respectively. H. fomes contributed the highest amount (82.9% of total AGM and 80.53% of total BGM) of above (193.56 Mg ha^?1) and belowground mass (107.09 Mg ha^?1) at the study site. Our study revealed structural attributes (tree diameter, height, and basal area) positively correlated with AGM. In contrast, species richness and species diversity negatively correlated with AGM. Our study indicated that lack of positive relationship between species diversity and AGM which may be attributable to high AGM of the dominant species (H. fomes) and may have a considerable consequence in AGM of the study area. Thus, maintaining large trees (DBH and height) rather than species diversity in the Sundarbans mangrove forest might be an effective approach for increasing aboveground mass.  相似文献   

Evidence of Spontaneous Recovery of Granulosa‐Theca Cell Tumour in a Heifer: A Retrospective Report          下载免费PDF全文

S Torisu  K Nibe  Y Kaneko  Y Hidaka  T Osawa 《Reproduction in domestic animals》2015,50(4):696-703

A 14‐month‐old Japanese Black heifer was evaluated on Day 0 (D 0) for enlargement of the right ovary (RO). Transrectal ultrasonography (TRUS) revealed that the RO was markedly enlarged and multicystic, while the left ovary (LO) was small and inactive. The presumptive diagnosis was granulosa‐theca cell tumour (GTCT), which was confirmed by markedly elevated plasma anti‐Müllerian hormone (AMH) of 4.42 ng/ml. Therefore, ovariectomy of the RO was the treatment of choice. The heifer was checked by TRUS and blood sampling on D 42, D 63 and immediately before ovariectomy on D 85. On D 42, TRUS did not show marked changes in either ovary in comparison with D 0. However, on D 63, the RO had transformed into a single cyst, and on D 85, the LO had resumed cyclic activity. The RO was extracted on D 85 by hand‐assisted laparoscopic ovariectomy to allow better control. Unexpectedly, histopathology revealed the lesion to be a fluid‐filled cystic structure, with no neoplastic proliferation of follicular epithelium that would indicate GTCT. The wall of the cystic structure consisted of collagen fibres and a few degenerated granulosa cells. The retrospective hormonal analysis revealed that the AMH concentrations had markedly dropped on D 63 and 85, which coincided with resumption of cyclicity in the LO. These findings suggest that the GTCT had self‐cured and transformed into a cyst‐like structure. The heifer then received an oestrous synchronization regime on D 105, was artificially inseminated on D 115 and became pregnant.  相似文献   

Carbon source and trophic position of pelagic fish in coastal waters of south-eastern Izu Peninsula,Japan, identified by stable isotope analysis     

Noriyuki Takai  Noriyuki Hirose  Takuya Osawa  Kazuyuki Hagiwara  Takahito Kojima  Yuji Okazaki  Tomohiro Kuwae  Toru Taniuchi  Kiyoshi Yoshihara 《Fisheries Science》2007,73(3):593-608

ABSTRACT:   It is important to clarify trophic dynamics in marine ecosystems for management of the fishing ground. Organic carbon sources and trophic position of pelagic fishes in the coastal waters of the south-eastern Izu Peninsula, Japan, were examined on the basis of carbon and nitrogen stable isotope distributions. The δ¹³C of the fishes was mostly distributed from −19 to −16‰ for nektonic fishes (13 species of adults and immatures) and planktonic fishes (10 species of larvae and juveniles), close to the δ¹³C values of particulate organic matter and planktonic decapods. These δ¹³C signatures for the inhabitants of the water column were in contrast with the high δ¹³C values (mainly −16 to −13‰) for demersal fishes of Scorpaeniformes and benthic polychaetes collected in the surf zone. These results indicate that nektonic and planktonic fishes depend on phytoplankton for carbon supply. The δ¹⁵N signatures suggest that the trophic position ranged 3.1–4.5 for the nektonic fishes and 2.9–3.7 for the planktonic fishes, premised on trophic level 3 for larval Japanese anchovy Engraulis japonicus . Thus, planktivorous fishes should be mainly assigned to trophic levels 3 and 4 in this area.  相似文献   

A G protein mutant that inhibits thrombin and purinergic receptor activation of phospholipase A2   总被引：7，自引：0，他引：7  

S K Gupta  E Diez  L E Heasley  S Osawa  G L Johnson 《Science (New York, N.Y.)》1990,249(4969):662-666

The stimulation of phospholipase A2 by thrombin and type 2 (P2)-purinergic receptor agonists in Chinese hamster ovary cells is mediated by the G protein Gi. To delineate alpha chain regulatory regions responsible for control of phospholipase A2, chimeric cDNAs were constructed in which different lengths of the alpha subunit of Gs (alpha s) were replaced with the corresponding sequence of the Gi alpha subunit (alpha i2). When a carboxyl-terminal chimera alpha s-i(38), which has the last 38 amino acids of alpha s substituted with the last 36 residues of alpha i2, was expressed in Chinese hamster ovary cells, the receptor-stimulated phospholipase A2 activity was inhibited, although the chimera could still activate adenylyl cyclase. Thus, alpha s-i(38) is an active alpha s, but also a dominant negative alpha i molecule, indicating that the last 36 amino acids of alpha i2 are a critical domain for G protein regulation of phospholipase A2 activity.  相似文献   

Antioxidative properties of phenolic antioxidants isolated from corn steep liquor     

Niwa T  Doi U  Kato Y  Osawa T 《Journal of agricultural and food chemistry》2001,49(1):177-182

With the immersion of corn into dilute sulfur oxide during starch-manufacturing processes, corn steep liquor (CSL) remains as leftover material. CSL is often used for fermentation, but its components are not fully understood. To determine the properties of CSL, 12 p-coumaric acid-related compounds were isolated from an ethyl acetate extract of CSL with the guidance of antioxidative activity on the rabbit erythrocyte membrane ghost system. The activity of these compounds was compared against oxidative damages, and it was elucidated that the activity of p-coumaric acid derivatives was mainly affected by their functional groups at the 3-position and less by the conjugated side chain. Moreover, p-coumaric acid derivatives exhibited inhibitory activity stronger than that of tocopherols and ascorbic acid on peroxynitrite-mediated lipoprotein nitration. These findings that p-coumaric acid derivatives, which might play a beneficial role against oxidative damage, exist in CSL suggest this byproduct might be a useful resource of phenolic antioxidants.  相似文献   

Chemical aspects of mutagen formation by sorbic acid-sodium nitrite reaction     

M Namiki  T Osawa  H Ishibashi  K Namiki  K Tsuji 《Journal of agricultural and food chemistry》1981,29(2):407-411

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Immunocytochemical Localization of Aromatase in The Ovary of Superovulated Cattle,Pigs and Sheep     

J. Lautincik  L. Kolodzieyski  V. Elias  P. Hyttel  Y. Osawa  A. Sirotkin 《Acta veterinaria Scandinavica》1994,35(2):185

Laurincik, J., L. Kolodzieyski, V. Elias, P. Hyttel, Y. Osawa, A. Sirotkin: Immunocytochemical localization of aromatase in the ovary of superovulated cattle, pigs and sheep. Acta vet. scand. 1994, 35, 185-191.–The localization of aromatase, an enzyme converting androgens to estrogen, in the ovaries of superovulated cattle, pigs and sheep was studied immunocytochemically in the preovulatory and postovulatory period using anti-human placental aromatase cytochrome P-450 antiserum. Immunostaining for aromatase was detected in the granulosa cells of preovulatory follicles of all species studied. Theca interna cells were stained in preovulatory follicles in the pig but not in cattle and sheep. Interstitial gland cells, cumulus cells and oocytes were unstained in all species. In cattle and pig the corpora lutea were unstained whereas they displayed staining in the sheep. Preantral and small antral follicles were unstained during both the preovulatory and postovulatory period in all species.It is concluded that granulosa cells of preovulatory follicles are the main residence for aromatase activity in superovulated cattle, pig and sheep, whereas the activity of theca interna and corpora lutea is species specific.  相似文献