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61.
Katsuhiro Shiono Masato Ejiri Kana Shimizu Sumiyo Yamada 《Plant Production Science》2013,16(2):285-295
ABSTRACT Root growth into hypoxic or anoxic waterlogged soil relies on internal aeration in plants. The plant hormone ethylene helps adapt to waterlogging by inducing the formation of aerenchyma, which provides a low-resistance pathway for the transport of oxygen from the shoot to the root apex. Waterlogging-susceptible crops including barley start to form aerenchyma after suffering waterlogging stress. But waterlogging can be fatal if aerenchyma formation is not fast enough. Here, we investigated whether pre-treating barley with ethephon, an ethylene-releasing agrochemical, could improve its tolerance to mimicked waterlogging conditions (using stagnant deoxygenated agar nutrient solution). In barley growing in aerated nutrient solution, ethephon treatment enhanced aerenchyma formation at the root tips and induced the development of shorter and shallower roots. Pre-treating barley leaves also delayed waterlogging-caused whiting and increased the percentages of viable root-tips under waterlogging conditions. However, the pretreatment did not noticeably increase fresh weight or shoot length. Further studies are needed to optimize ethephon treatment conditions to improve barley production under waterlogged conditions. 相似文献
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Tatsuo NAKAHARA Yoshihisa UENOYAMA Akira IWASE Shinya OISHI Sho NAKAMURA Shiori MINABE Youki WATANABE Chikaya DEURA Taro NOGUCHI Nobutaka FUJII Fumitaka KIKKAWA Kei-ichiro MAEDA Hiroko TSUKAMURA 《The Journal of reproduction and development》2013,59(5):479-484
Puberty in mammals is timed by an increase in gonadotropin-releasing hormone (GnRH)
secretion. Previous studies have shown involvement of the two neuropeptides,
kisspeptin and neurokinin B (NKB), in controlling puberty onset. Little is known
about the role of the other key neuropeptide, dynorphin, in controlling puberty
onset, although these three neuropeptides colocalize in the arcuate kisspeptin
neurons. The arcuate kisspeptin neuron, which is also referred to as the KNDy neuron,
has recently been considered to play a role as an intrinsic source of the GnRH pulse
generator. The present study aimed to determine if attenuation of inhibitory
dynorphin-kappa-opioid receptor (KOR) signaling triggers the initiation of puberty in
normal developing female rats. The present study also determined if stimulatory
NKB-neurokinin 3 receptor (NK3R) signaling advances puberty onset. Female
Wistar-Imamichi rats were weaned and intraperitoneally implanted with osmotic
minipumps filled with nor-binaltorphimine (nor-BNI), a KOR antagonist, or senktide, a
NK3R agonist, at 20 days of age. Fourteen days of intraperitoneal infusion of nor-BNI
or senktide advanced puberty onset, manifested as vaginal opening and the first
vaginal estrus in female rats. Frequent blood sampling showed that nor-BNI
significantly increased luteinizing hormone (LH) pulse frequency at 29 days of age
compared with vehicle-treated controls. Senktide tended to increase this frequency,
but its effect was not statistically significant. The present results suggest that
the inhibitory input of dynorphin-KOR signaling plays a role in the prepubertal
restraint of GnRH/LH secretion in normal developing female rats and that attenuation
of dynorphin-KOR signaling and increase in NKB-NK3R signaling trigger the onset of
puberty in female rats. 相似文献
63.
Comparison of Ethylene Glycol and Propylene Glycol for the Vitrification of
Immature Porcine Oocytes
Tamás SOMFAI Michiko NAKAI Fuminori TANIHARA Junko NOGUCHI Hiroyuki KANEKO Naomi KASHIWAZAKI István EGERSZEGI Takashi NAGAI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2013,59(4):378-384
Our aim was to optimize a cryoprotectant treatment for vitrification of immature porcine
cumulus-oocyte complexes (COCs). Immature COCs were vitrified either in 35% ethylene
glycol (EG), 35% propylene glycol (PG) or a combination of 17.5% EG and 17.5% PG. After
warming, the COCs were in vitro matured (IVM), and surviving oocytes were
in vitro fertilized (IVF) and cultured. The mean survival rate of
vitrified oocytes in 35% PG (73.9%) was higher (P<0.05) than that in 35% EG (27.8%).
Oocyte maturation rates did not differ among vitrified and non-vitrified control groups.
Blastocyst formation in the vitrified EG group (10.8%) was higher (P<0.05) than that in
the vitrified PG group (2.0%) but was lower than that in the control group (25.0%).
Treatment of oocytes with 35% of each cryoprotectant without vitrification revealed a
higher toxicity of PG on subsequent blastocyst development compared with EG. The
combination of EG and PG resulted in 42.6% survival after vitrification. The maturation
and fertilization rates of the surviving oocytes were similar in the vitrified, control
and toxicity control (TC; treated with EG+PG combination without cooling) groups.
Blastocyst development in the vitrified group was lower (P<0.05) than that in the
control and TC groups, which in turn had similar development rates (10.7%, 18.1% and
23.3%, respectively). In conclusion, 35% PG enabled a higher oocyte survival rate after
vitrification compared with 35% EG. However, PG was greatly toxic to oocytes. The
combination of 17.5% EG and 17.5% PG yielded reasonable survival rates without toxic
effects on embryo development. 相似文献
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Dirk Schenke Kana Naito Kazuhiro Toyoda Yoshishige Inagaki Tomonori Shiraishi Yuki Ichinose 《Journal of General Plant Pathology》2005,71(4):273-279
INF1 elicitin, a proteinaceous elicitor produced by Phytophthora infestans, induces a hypersensitive response in tobacco BY-2 cells. In response to elicitin, tobacco cells produce both reactive oxygen species (ROS) and ethylene (ET). To investigate the regulation of elicitin-induced ET production, we pharmacologically analyzed the effects of several chemicals on ET production. Inhibitors of ROS generation or ROS chelators efficiently inhibited ET production, whereas simultaneous treatment of a superoxide anion-generating system with salicylhydroxamic acid recovered ET production. In an in vitro experiment, superoxide anion was necessary and sufficient for conversion of 1-aminocyclopropane-1-carboxylate (ACC) to ET because ET was produced from ACC solely in the presence of the superoxide-generating chemical KO2. ET production was also inhibited by lipoxygenase (LOX) inhibitors, indicating a possible involvement of LOX-mediated generation of superoxide anion and ET production itself. Furthermore, elicitin-induced ET production was completely inhibited by the protein synthesis inhibitor cycloheximide but recovered after exogenous application of ACC, indicating that de novo protein synthesis is required for ACC accumulation, leading to ET production. We also investigated the effects of several phytohormones on elicitor-induced ET production and discuss their role in the defense response. 相似文献
66.
Yoshihara S Hattori J Nishizono K Kawamura A Shimozaki K Nishida Y Oda K Tsuji N Hirayama N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(10):1129-1131
Group A consisted of chickens infected with a single dose of Ascaris suum and group B of chickens infected with two successive doses. At days 1, 3, 7, 14 and 21 after the first or second infection dose, six chickens from each group were sacrificed. In both groups, larvae were recovered from the livers on days 1, 3, and 7 and lungs on days 3 and 7. No larvae were detected in chickens on day 14. Clear white lesions were noticed only on the livers from chickens of group B at day 7 but had disappeared at day 14. A comparison with group B showed mild histological changes that developed relative to the livers from group A. 相似文献
67.
Sachi TANAKA Yasuhiro NAGAI Yoko NOGUCHI Masato MIYAKE Kouichi WATANABE Shyuichi OHWADA Hisashi ASO Takahiro YAMAGUCHI 《Animal Science Journal》2008,79(5):597-604
Although distinct cytokine expression in T cell subsets is well understood in mice and humans, limited information is available on bovine T cell subsets. In the present study, we analyzed the mRNA expression of 10 kinds of cytokines and CD25 expression in CD4+ , CD8+ , WC1+ and WC1- γδ T cell subsets in bovine peripheral blood by Concanavalin A (Con A) stimulation. CD25 expression was significantly increased in CD4+ , CD8+ and WC1+ γδ T cells, but not in WC1- γδ T cells by Con A stimulation. In CD4+ T cells, the mRNAs of Interleukin (IL)-2, IL-6, IL-10, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, TNF-β and transforming growth factor (TGF)-β were expressed in control cultures, and IL-3, IL-4 and granulocyte-macrophage colony stimulating factor (GM-CSF) were newly expressed when the cells were stimulated with Con A. CD8+ T cells expressed the mRNAs of IL-6, TNF-α, TNF-β and TGF-β in control cultures, and newly expressed those of IL-2, IFN-γ and GM-CSF, but did not express those of IL-3, IL-4 or IL-10 after Con A stimulation. The cytokine expression profile of WC1+ γδ T cells was similar to that of CD8+ T cells. However, WC1- γδ T cells did not express any cytokine mRNA except TGF-â mRNA. These results will contribute to elucidate the participation of T cell subsets in immune responses against infectious disease in cattle. 相似文献
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Ken-ichiro TATEMATSU Mitsumi IKEDA Yoshihiro WAKABAYASHI Takashi YAMAMURA Kazuhiro KIKUCHI Junko NOGUCHI Hideki SEZUTSU 《The Journal of reproduction and development》2021,67(6):402
Porcine zona pellucida proteins (ZPs) have been utilized as female immunocontraceptive antigens. The purpose of this study was to explore the potential use of silkworm recombinant bovine ZP4 as an alternative. When the protein was injected with monophosphoryl lipid A (MPL) – an immuno-stimulative agent – into two female goats, marked elevation of the anti-ZP4 titer was detected. Application of the purified specific IgG to a porcine in vitro fertilization system reduced the sperm penetration rate. In one goat, the cyclic profile of serum progesterone disappeared as the anti-ZP4 titer increased. Histological examination of the ovaries revealed degeneration of antral follicles with sparse infiltration of inflammatory cells in the theca, indicating that autoimmune oophoritis had been induced. Together, the present results suggest that recombinant ZP4 disturbs fertilization and exerts a pathogenic effect on follicle development in goats, thus indicating its potential as a female immunocontraceptive antigen. 相似文献