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51.
Masato MIYAKE Shinichiro HAYASHI Yoshikazu TAKETA Shunsuke IWASAKI Kouichi WATANABE Shyuich OHWADA Hisashi ASO Takahiro YAMAGUCHI 《Animal Science Journal》2010,81(2):223-229
Myostatin (MSTN) is a negative regulator during muscle differentiation, whereas insulin‐like growth factors (IGFs) are essential for muscle development. MSTN and IGFs act oppositely during myogenesis, but there is little information on the mutual relationship of MSTN and IGFs. The present study was conducted to examine whether MSTN affects IGF expression during early myogenesis in cattle. IGF‐1 mRNA was similarly expressed in M. longissimus thoracis of double‐muscled (DM) and normal (NM) Japanese shorthorn cattle. IGF‐2 mRNA expression was consistently higher in the normal and regenerating muscle of DM cattle than those of NM cattle. When myoblasts were isolated from regenerating M. longissimus thoracis, IGF‐2 mRNA expression showed a significant increase in differentiating DM derived myoblasts (DM‐myoblasts) as compared with differentiating NM derived myoblasts (NM‐myoblasts). An addition of recombinant mouse myostatin (rMSTN) to myoblast cultures attenuated IGF‐2 mRNA expression and decreased myotube formation, but did not effect IGF‐1 mRNA expression. An activin‐like kinase (ALK) inhibitor, SB431542, mediates MSTN action, suppressed the translocation of Smad2/3 into the nucleus in DM‐myoblasts, and restored the attenuated IGF‐2 mRNA expression and the decreased myotube formation induced by rMSTN in myoblast cultures. The findings indicate that MSTN may negatively regulate myoblast differentiation by suppressing IGF‐2 expression via ALK‐Smad signaling. 相似文献
52.
RNA-silencing suppressors of geminiviruses 总被引:2,自引:0,他引:2
53.
Nakamura Masato Oritate Fumiko Yuyama Yoshito Yamaoka Masaru Dan Nguyen Phuoc Hanh Dang Vu Bich 《Paddy and Water Environment》2018,16(1):193-198
Paddy and Water Environment - In some areas of Vietnam, digested slurry from biogas digesters is discharged into canals without wastewater treatment. In order to reduce environmental pollution,... 相似文献
54.
Yoshikazu TAKETA Yasuhiro NAGAI Hideki OGASAWARA Shinichiro HAYASHI Masato MIYAKE Sachi TANAKA Kouichi WATANABE Shyuichi OHWADA Hisashi ASO Takahiro YAMAGUCHI 《Animal Science Journal》2008,79(3):382-390
Myostatin (MSTN), known as growth and differentiation factor 8 (GDF-8), is a member of the transforming growth factor β (TGF-β) superfamily that negatively regulates skeletal muscle mass. Myostatin binds with high affinity to the receptor serine threonine kinase activin receptor type IIB (ActRIIB). Activins that also belong to the TGF-β superfamily, stimulate follicle-stimulating hormone production in gonadotrophs and suppress growth hormone and adrenocorticotropic hormone production in somatotrophs and corticotrophs, respectively. The aim of the present paper was therefore to clarify the endocrine action of MSTN in adenohypophysis. The present study details the expression and cellular localization of MSTN and ActRIIB in porcine anterior pituitary gland. The mRNA of MSTN and ActRIIB was consistently expressed in RT-PCR. Immunohistochemistry of MSTN and specific hormones showed that MSTN localized in thyrotrophs and gonadotrophs, in which most of the MSTN immunoreactive cells were identified as thyrotrophs. The immunostaining of ActRIIB was restricted to corticotrophs. These results indicate that MSTN was mainly produced in thyrotrophs and its receptor, ActRIIB, was restrictively contained in corticotrophs. Interestingly, thyrotrophs immunoreactive for MSTN were frequently close to corticotrophs immunoreactive for ActRIIB. The present study suggests that MSTN from thyrotrophs may regulate corticotroph function as a paracrine mediator among the porcine anterior pituitary cells. 相似文献
55.
Kaoru YAMAZAKI Takehito SUZUKI Mitsuyuki SHIRAI Tatsuya TAKIZAWA Tadashi SHINODA Toshio MASAOKA Fumiaki AKAHORI Hidetoshi MORITA 《Animal Science Journal》2008,79(3):391-400
The effect of the endocrine-disrupting chemical 3,3',4,4',5-pentachlorobiphyenl (PCB 126) on intestinal microbiota after oral administration, and the improvement of intestinal microbiota and feces quantity by the subsequent administration of Lactobacillus acidophilus or Lactobacillus reuteri was investigated. All the rats were given 100 μg/kg bodyweight of PCB 126. The changes in bacterial counts were confirmed using a culture method. The administration of PCB 126 tended to decrease the bacterial counts of lactobacilli (109.6 −1010.2 to 108.8 −109.2 ) and bifidobacteria (105.3 −106.1 to 103.6 −104.2 ), and to increase those of Enterobacteriaceae (108.2 −109.1 to 109.4 −1010.3 ) and staphylococci (106.6 −107.4 to 107.2 −108.4 ) compared to no PCB 126 administration. After administration of PCB 126, L. acidophilus or L. reuteri orally administered to rats caused Enterobacteriaceae and staphylococci counts to decrease, suggesting that the intestinal microbiota was improved by the lactobacilli. The administration of L. acidophilus and L. reuteri improved the balance of intestinal microbiota, and defecation volume returned to its normal level. L. acidophilus and L. reuteri have a remedial effect on intestinal microbiota affected by PCB 126 and can function to lessen accumulated PCB 126 volume. 相似文献
56.
This study aimed to reveal the effects of direct exposure to cold weather under grazing in winter (GW) on the health of Japanese Black beef cattle, as assessed using physiological, immunological, and behavioral parameters. Ten Japanese Black beef cattle (328 ± 45 kg, 7.6 ± 3.4 years of age) were used in this experiment. In winter, five of the 10 cattle grazed for 2 months in a 1.8 ha pasture (GW), and the remaining cattle were fed under confined conditions with tethering (control [CT]). The two groups were fed similar feed during the experiment, except for the grazing forage. Blood samples were collected approximately every 2 weeks. The numbers of neutrophils and monocytes and antioxidant enzyme activity were higher in the GW group than in the CT group (p < 0.05). The proportions of CD4‐single‐positive cells were lower in GW cattle than in CT cattle (p = 0.06). This study showed that direct exposure of beef cattle to cold weather under GW enhanced the levels of circulating neutrophils and monocytes and contributed to the kinetic homeostasis of lymphocytes but also activated antioxidant enzymes due to an increase in oxidative stress. 相似文献
57.
Masaya Igase Chung Chew Hwang Satoshi Kambayashi Masato Kubo Matt Coffey Takako Shimokawa Miyama Kenji Baba Masaru Okuda Shunsuke Noguchi Takuya Mizuno 《Canadian journal of veterinary research》2016,80(1):21-31
The oncolytic effects of reovirus in various cancers have been proven in many clinical trials in human medicine. Oncolytic virotherapy using reovirus for canine cancers is being developed in our laboratory. The objective of this study was to examine the synergistic anti-cancer effects of a combination of reovirus and low doses of various chemotherapeutic agents on mammary gland tumors (MGTs) in dogs. The first part of this study demonstrated the efficacy of reovirus in canine MGTs in vitro and in vivo. Reovirus alone exerted significant cell death by means of caspase-dependent apoptosis in canine MGT cell lines. A single injection of reovirus impeded growth of canine MGT tumors in xenografted mice, but was insufficient to induce complete tumor regression. The second part of this study highlighted the anti-tumor effects of reovirus in combination with low doses of paclitaxel, carboplatin, gemcitabine, or toceranib. Enhanced synergistic activity was observed in the MGT cell line treated concomitantly with reovirus and in all the chemotherapeutic agents except toceranib. In addition, combining reovirus with paclitaxel or gemcitabine at half dosage of half maximal inhibitory concentration (IC50) enhanced cytotoxicity by activating caspase 3. Our data suggest that the combination of reovirus and low dose chemotherapeutic agents provides an attractive option in canine cancer therapy. 相似文献
58.
Aoyama M Negishi A Abe A Yokoyama R Ichimaru T Sugita S 《Veterinary journal (London, England : 1997)》2008,177(1):116-123
This study investigated the effects of an intracerebroventricular (ICV) injection of corticotropin releasing hormone (CRH) on physiological and behavioural responses in goats. In Experiment 1, saline (control) or saline plus 25 microg of ovine CRH was injected into the third ventricle of castrated male goats. CRH increased plasma cortisol (Cor) levels markedly within 15 min, but had little effect on plasma glucose (Glu). Compared with saline injected goats, CRH decreased the total duration of lying behaviour but increased its frequency, and suppressed rumination and self-grooming. In Experiment 2, the effects of an intravenous (IV) injection of human adrenocorticotropic hormone (ACTH) (1-24) (0.1mg) were examined and an IV injection of saline was used as control. ACTH increased plasma Cor levels markedly, but did not change any behaviour compared with controls. It was concluded that CRH mediated the response of the hypothalamus-pituitary-adrenal (HPA) axis and behaviour following stress in goats, although the CRH-induced behavioural changes were independent of the HPA axis and seemed to be the result of direct action within the central nervous system. 相似文献
59.
To study spatial variation in natural tree seedling density and the relationship between variation in seedling density and
seed dispersal mode at a cleared site, we surveyed natural tree seedlings after the site preparation for planting in a coniferous
plantation cleared by a typhoon disturbance in 2004. The site was located near Sikotsuko Lake, Hokkaido, northern Japan. Twenty-five
tree seedling species were found and the mean seedling density was 9.8 seedlings/m2. Seedlings of non-animal-dispersed species (7.2 seedlings/m2) were approximately five times more abundant than those of animal-dispersed species (1.4 seedlings/m2), and 87% of all seedlings were current. The seedling density of non-animal-dispersed species (almost all wind-dispersed)
decreased with distance from a natural forest; however, this trend did not hold for animal-dispersed species (almost all bird-dispersed).
The spatial variation in seedling density was lower in animal-dispersed species than in non-animal-dispersed species. Seed
dispersal patterns and the viability duration of buried seeds likely affected the variation in seedling density by seed dispersal
mode. 相似文献
60.
Stand Density Control Diagrams for Scots pine and Austrian black pine plantations in Bulgaria 总被引:1,自引:0,他引:1
Stand Density Control Diagram (SDCD) is a stand-level mathematical model, which describes the relationships between yield,
density and mortality throughout all stages of stand development. The SDCD is primarily used to derive density control schedules
by management objectives. The main objectives of the present study are to define a modified model of SDCD for application
to Scots pine (Pinus sylvestris L.) and Austrian black pine (Pinus nigra Arn.) plantations in Bulgaria, to examine the fitness of the model with representative experimental data sets from plantations
of both species and to present a way of direct application of the SDCDs for practical purposes. The constructed SDCDs characterize
the spatial-temporal dynamics of the pine plantations in a broad range of densities, forest sites and growth stages from 4
to 26 (28) m of dominant height class. The full density lines were fixed with self-thinning exponents α = 1.69 and α = 1.75
for Scots pine and Austrian black pine, respectively, and the trajectories of natural thinning for 23 initial densities (444-40000/ha)
were determined. A direct way for application of the SDCDs to the plantation management was designed to estimate the optimal
initial densities for the maximum attainable final yield and large-size wood production by self-thinning stands. 相似文献