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61.
62.
Iwata K Kinoshita M Susaki N Uenoyama Y Tsukamura H Maeda K 《The Journal of reproduction and development》2011,57(3):379-384
Ketosis is found in various pathophysiological conditions, including diabetes and starvation, that are accompanied by suppression of gonadal activity. The aim of the present study was to determine the role of ketone body in the brain in regulating pulsatile luteinizing hormone (LH) secretion in female rats. Injection of 3-hydroxybutyrate (3HB), a ketone body, into the fourth cerebroventricle (4V) induced suppression of pulsatile LH secretion in a dose-dependent manner in ovariectomized (OVX) rats with an estradiol (E2) implant producing diestrus plasma E2 levels. Plasma glucose and corticosterone levels increased immediately after the 4V 3HB injection, suggesting that the treatment caused a hunger response. The 3HB-induced suppression of LH pulses might be mediated by noradrenergic inputs to the hypothalamic paraventricular nucleus (PVN) because a local injection of α-methyl- p-tyrosine, a catecholamine synthesis inhibitor, into the PVN blocked 3HB-induced suppression of LH pulses and PVN noradrenaline release was increased by 4V 3HB injection in E2-primed OVX rats. These results suggest that ketone body sensed by a central energy sensor in the hindbrain may suppress gonadotropin release via noradrenergic inputs to the PVN under ketosis. 相似文献
63.
Cloned porcine embryos can maintain developmental ability after cryopreservation at the morula stage
Nakano K Matsunari H Nakayama N Ogawa B Kurome M Takahashi M Matsumoto M Murakami H Kaji Y Nagashima H 《The Journal of reproduction and development》2011,57(2):312-316
The aim of the present study was to clarify the overall efficiency of porcine somatic cell nuclear transfer (SCNT) by incorporating cryopreservation of the cloned embryos before transfer. The SCNT embryos reconstructed with preadipocytes and in vitro-matured (IVM) oocytes were cultured to harvest morula stage embryos; they were then subjected to delipation (removal of cytoplasmic lipid droplets) and vitrification. After warming and culture, the embryos developing to blastocysts were transferred to recipients to obtain cloned piglets. From 372 reconstructed embryos, 188 (50.5%) reached the morula stage and 117 (31.5%) developed to blastocysts after vitrification. Transfer of 98 (26.3%) morphologically normal blastocysts gave rise to 6 (1.6%) piglets, including 1 stillborn. The efficiency of the cloned piglet production was comparable with that obtained using SCNT embryos without cryopreservation (2.7%, 17/635). Here, we demonstrate that porcine somatic cell cloning can be performed without a significant reduction in efficiency even when the SCNT embryos are cryopreserved before transfer. 相似文献
64.
65.
Naoki Isobe Shoko Matsukawa Kota Kubo Kazutoshi Ueno Toshihisa Sugino Takahiro Nii Yukinori Yoshimura 《Animal Science Journal》2020,91(1)
The present study was conducted to examine whether colostrum supplementation in peripartum goats increases the antimicrobial peptides in their milk. Goats were orally administered 2 ml of colostrum whey products (colostrum group) or water (control group) daily, from 2 weeks before until 2 weeks after kidding. Body weights of mothers and kids were measured. Blood, milk, and fecal samples were collected from the mothers, and blood samples were collected from the kids. Concentrations of milk antimicrobial peptides (beta‐defensin, cathelicidin, lactoferrin, S100A7, lactoperoxidase, and immunoglobulin A [IgA]) were determined. IgA and nutritional parameters (glucose, total cholesterol, triglyceride, ketone bodies, and non‐esterified fatty acids) were also determined in the blood of mothers and kids. Milk IgA and lactoferrin concentrations were higher in the colostrum group than in the control group. Conversely, lower milk concentrations of S100A7 were observed in the colostrum group than that in the control group. Plasma IgA concentrations were higher for kids from the colostrum group than for those from the control group. These results suggest that oral administration of colostrum in pregnant goats increases IgA concentration in postpartum milk, which can subsequently improve the health of their kids. 相似文献
66.
Naoki Mori Shoji Ohta Hajime Chiba Toshiya Takagi Yukiko Niimi Vasant Shinde Mukund D. Kajale Toshiki Osada 《Genetic Resources and Crop Evolution》2013,60(6):1771-1775
Indian dwarf wheat (Triticum aestivum L. ssp. sphaerococcum (Perc.) Mac Key, synonym: T. sphaerococcum Perc.) is endemic to southern Pakistan and northwestern India. It was one of the main winter crops grown by ancient Indian cultures. However, it disappeared from the record during the early twentieth century, especially after the Green Revolution brought modern wheat varieties into India and Pakistan. Whether or not Indian dwarf wheat is presently cultivated has been unclear. Here we report on the rediscovery of the cultivation of this wheat in northern Karnataka and southern Maharashtra in India. Molecular genetic analysis of the chloroplast DNA of the two specimens collected at location 3 revealed that both samples have a unique haplotype that is specific to Indian dwarf wheat. We found this wheat at three locations in 2010, but at only one of the three locations in 2011. Therefore, the future survival of this subspecies is uncertain. Further ethnobotanical research is urgently needed to conserve this unique genetic resource for the future. 相似文献
67.
Textures of six cabbage cultivars were quantified using an acoustical vibration technique. A sample of four outer leaves of a cabbage was penetrated using a probe. The acoustical vibration signals were measured during penetration using a piezoelectric sensor. A new texture index (TI), the “energy density”, was introduced, which was determined by the integration of squared amplitudes of texture signals multiplied by a factor of a frequency band. This TI enabled evaluation of acoustical signals in the high-frequency region (>1000 Hz) more sensitively than the previously used index (“amplitude density”), which was determined by the integration of texture signal amplitudes. Significant differences in TI among the cultivars were obtained by using ANOVA, especially between a spring and a winter cabbage. We also examined cabbages that had been stored under 4 °C for 10 or 19 d. Most TI readings increased after the storage. These results provide useful information related to the shelf-life of cabbages. 相似文献
68.
Cytological characteristics of microconidia of <Emphasis Type="Italic">Magnaporthe oryzae</Emphasis>
Izumi Chuma Takeshi Shinogi Naoki Hosogi Ken-ichi Ikeda Hitoshi Nakayashiki Pyoyun Park Yukio Tosa 《Journal of General Plant Pathology》2009,75(5):353-358
The inner cellular structure of microconidia of Magnaporthe oryzae was examined using fluorescent probes and electron microscopic techniques. The volume of the nucleus relative to the cell
was significantly larger in microconidia than in macroconidia or vegetative hyphae, similar to observations for spermatia
of other fungi. Selective fluorescent staining revealed that cytosolic RNA was less abundant in microconidia than in macroconidia
and germ tubes, suggesting that general metabolic activity in microconidia is low. Consistently, GFP expression driven by
the TrpC promoter was highly active during the formation of phialides and microconidia but gradually decreased as the microconidia
matured. Such data suggest that microconidia are in a quiescent or dormant state. 相似文献
69.
Hiro HORIKIRIZONO Kumiko ISHIGAKI Keigo IIZUKA Kei TAMURA Naoki SAKURAI Kazuyuki TERAI Tatsuya HEISHIMA Orie YOSHIDA Kazushi ASANO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(5):720
Angiogenesis plays an important role in the proliferation and metastasis mechanisms of malignant tumors. Vascular endothelial growth factor (VEGF), a group of cytokines that contribute to angiogenesis and vasculogenesis. This study aimed to investigate the serum VEGF-A concentrations in dogs with various proliferative diseases. A total of 202 dogs that were histopathologically diagnosed with proliferative diseases were included in the study. Serum VEGF-A concentrations were measured using enzyme-linked immunosorbent assay. Median serum VEGF-A concentrations in dogs were as follows: healthy dogs, 4 pg/ml [0–21 pg/ml]; hepatocellular carcinoma, 30 pg/ml [0–158 pg/ml, P=<0.001]; hepatocellular adenoma, 32 pg/ml [0–49 pg/ml, P=0.003]; hepatic nodular hyperplasia, 18 pg/ml [0–51 pg/ml, P=0.595]; adrenal pheochromocytoma, 32 pg/ml [0–187 pg/ml, P=<0.001]; adrenocortical carcinoma, 32 pg/ml [3–161 pg/ml, P=0.002]; adrenocortical adenoma, 27 pg/ml [0–106 pg/ml, P=0.005]; colorectal adenocarcinoma, 36 pg/ml [0–75 pg/ml, P=0.002]; colorectal adenoma, 43 pg/ml [0–48 pg/ml, P=0.144]; inflammatory colorectal polyps, 37 pg/ml [0–111 pg/ml, P=<0.001]; pulmonary adenocarcinoma, 35 pg/ml [4–107 pg/ml, P=0.002]; pulmonary histiocytic sarcoma, 35 pg/ml [0–131 pg/ml, P=0.016]; and follicular thyroid carcinoma, 35 pg/ml [0–106 pg/ml, P=0.009]. The serum VEGF-A concentrations were significantly higher in dogs with neoplastic lesions compared to healthy dogs, except for colorectal adenoma. High serum VEGF-A concentrations were observed in dogs with proliferative diseases. The present study suggests that angiogenesis-inhibiting therapy, which targets VEGF-A, may be useful for canine neoplastic diseases. 相似文献
70.
Glutathione S-alkyl- and S-aryltransferase activities and the glutathione-dependent reactions involved in the metabolism of diazinon, parathion, DDT and γ-BHC were determined in two susceptible and three resistant housefly strains. The relative rate of formation of desethyl diazinon and desethyl parathion and the degradation of γ-BHC paralleled the activities of the alkyl and aryltransferases in the various strains of houseflies suggesting that a single enzyme might be involved. DDT-dehydrochlorinase showed different relative rates among the strains indicating that the dechlorination was catalyzed by a different enzyme. The enzyme responsible for the conjugation of the pyrimidinyl moiety of diazinon appears to be different from the one which catalyzes the conjugation of the p-nitrophenyl moiety of parathion. The dearylation reactions were not mediated by the glutathione S-aryltransferase in the various housefly strains. 相似文献