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371.
Bao RM Hayakawa K Moniruzzaman M Taketsuru H Miyano T 《The Journal of reproduction and development》2011,57(4):475-480
The objective of the present study was to elucidate the involvement of FOXO3 in the activation of bovine primordial follicles. In immunohistochemistry, FOXO3 was detected in all of the oocytes in primordial and primary follicles. The FOXO3 decreased after treatment with FOXO3 small interfering RNAs (siRNAs). Ovarian tissues containing dominantly primordial follicles were treated with FOXO3 siRNAs and then xenografted to severe combined immune deficiency (SCID) mice. Two months after xenografting, some primordial follicles developed to the secondary and tertiary stages, and the total percentage of these developing follicles (secondary and tertiary follicles: 18 ± 7%) was higher than in the control grafts treated with control siRNA (7 ± 1%). It is thought that bovine primordial follicle activation is regulated by the FOXO3-dependent mechanism and that knockdown of FOXO3 induces the release of primordial follicles from FOXO3 suppression, initiating their growth. 相似文献
372.
Yasuno H Nagai H Ishimura Y Watanabe T Yamasaki H Anayama H Takai Y Yamauchi H Hara Y Murai F Kandori H 《Journal of toxicologic pathology》2011,24(2):131-135
The histologic characteristics of a salivary mucocele in a beagle used in a toxicity study are described in this report. A pale yellowish cyst under the mandibular skin containing frothy mucus was observed at necropsy. Microscopically, numerous villous projections arose from the internal surface of the cyst and were lined by stratified epithelial-like macrophages, which were immunopositive for macrophage scavenger receptor A. A ruptured sublingual interlobar duct connected to the lumen was observed near the cyst. Luminal amorphous material showed a positive reaction with Alcian blue and periodic acid-Schiff staining as did mucin in the sublingual gland. Ultrastructurally, the epithelial-like macrophages had numerous vacuoles containing electron-lucent material, which was presumed to be lysosomal in origin, and had pseudopods on their cell surfaces interdigitating with those on the adjacent cells. This case report helps to understand the diversity of the background findings in beagles used in toxicity studies. 相似文献
373.
Shunsuke Hara Sogo Aoki Miki Nagata Koumei Shirasuna Tatsuo Noguchi Hisataka Iwata 《Reproduction in domestic animals》2020,55(9):1124-1131
One of the major difference between the in vivo and in vitro embryonic environments is the stiffness of the culture substrate. Xanthan gum (XG) and locust bean gum (LBG) are natural materials that are safe, inexpensive and easy to handle. In this study, we investigated the effects of using a polysaccharide culture substrate made from 1% XG and 1% LBG (XG-LBG gel) on bovine embryonic development. Oocytes collected from bovine ovaries were subjected to maturation, and fertilization to generate embryos at an early developmental stage (>4 cell stage). Cleaved embryos were further cultured in a well of 96-well cell culture plate coated with or without XG-LBG gel for 5 days. While the developmental rate up to the blastocyst stage did not differ between the two culture systems (control, 38.0 vs. gel, 38.6%), blastocysts developed on the XG-LBG gel produced significantly high cell numbers and ATP content. Embryos cultured on XG-LBG gels for 24 hr had high expression levels of F-actin and a highly even distribution of E-cadherin. In addition, embryos developed on XG-LBG gel demonstrated increased translocation of YAP to the nucleus and increased connective tissue growth factor (CTGF) protein levels (downstream of Hippo signalling). These findings suggest that soft culture substrates improve embryonic development by enhancing mechanotransduction, including YAP-CTGF signalling. 相似文献
374.
Yoichi Sakamoto Kiyotoshi Hasegawa Shunsuke Moriwaki Yoko Hara Yuta Hamada Shinji Sasaki 《Animal Science Journal》2020,91(1)
Recessive missense mutation in the solute carrier family 12, member 1 (SLC12A1) gene (g.62382825G>A) is associated with hydrallantois, which is the accumulation of fluid in the allantoic cavity of a pregnant animal, and usually causes fetal death in Japanese Black cattle. However, the symptoms of a homozygote with this mutation that do not result in fetal death have not previously been tracked and evaluated. In the present study, we observed a homozygote with the SLC12A1 risk allele over a long‐term period. The calf did not show any obvious clinical symptoms, although it did exhibit a slight growth retardation that accompanied mild calciuria. At 28 months of age, the homozygote showed renal dysfunction, which in turn resulted in hydronephrosis. The time course of the symptoms was consistent with the phenotype of Bartter syndrome in humans. Additionally, the risk heterozygous genotype did not any effects on carcass traits, which indicates that eliminating the risk allele would not have any unfavorable effects. Therefore, we emphasize that both the fetal‐ and late‐stage symptoms associated with the SLC12A1 risk allele compromise animal welfare, and consequently may result in severe economic losses for individual farmers if the SLC12A1 risk allele is not eliminated from the population. 相似文献
375.
Kumita Kohei Kitazawa Yugo Tokuda Ryosuke Miyazaki Akio Maejima Kensaku Namba Shigetou Yamaji Yasuyuki 《Journal of General Plant Pathology》2021,87(4):254-258
Journal of General Plant Pathology - In July 2018, tillandsia (Tillandsia sp.) plants with brown to dark brown lesions on the leaves and pseudobulbs were found in Japan. Based on morphological and... 相似文献
376.
Yoshihiro WAKABAYASHI Takashi YAMAMURA Kohei SAKAMOTO Yuji MORI Hiroaki OKAMURA 《The Journal of reproduction and development》2013,59(1):40-48
Neurons in the arcuate nucleus (ARC) that concomitantly express kisspeptin, neurokinin B
(NKB) and dynorphin A are termed KNDy neurons and are likely candidates for the intrinsic
gonadotropin-releasing hormone (GnRH) pulse generator. Our hypothesis is that KNDy neurons
are functionally and anatomically interconnected to generate discrete neural signals that
govern pulsatile GnRH secretion. Our goal was to address this hypothesis using
electrophysiological and anatomical experiments in goats. Bilateral electrodes targeting
KNDy neurons were implanted into ovariectomized goats, and GnRH pulse generator activity,
represented by characteristic increases in multiple-unit activity (MUA volleys), was
measured. Spontaneous and pheromone- or senktide (an NKB receptor agonist)-induced MUA
volleys were simultaneously recorded from both sides of the ARC. An anterograde tracer,
biotinylated dextran amine (BDA), was also injected unilaterally into the ARC of castrated
male goats, and the distribution of fibers containing both BDA and NKB was examined using
dual-labeling histochemistry. The results showed that MUA volleys, regardless of origin
(spontaneous or experimentally induced), occur simultaneously between the right and left
sides of the ARC. Tract tracing indicated that axons projecting from NKB neurons in the
ARC were directly apposed to other NKB neuronal cells located bilaterally in the ARC.
These results demonstrate that GnRH pulse generator activity occurs synchronously between
both sides of the ARC in goats and that KNDy neurons are bilaterally interconnected in the
ARC via NKB-containing fibers. Taken together, the results suggest that KNDy neurons form
a neuronal circuit to synchronize burst activity among KNDy neurons and thereby generate
discrete neural signals that govern pulsatile GnRH secretion. 相似文献
377.
Background
Brucella is a group of bacteria that causes brucellosis, which can affect population health and reproductive success in many marine mammals. We investigated the serological prevalence of antibodies against Brucella bacteria in a declining harbor seal population in Glacier Bay National Park, Alaska.Results
Prevalence ranged from 16 to 74 percent for those tests detecting antibodies, indicating that harbor seals in Glacier Bay have been exposed to Brucella bacteria. However, the actual level of serological prevalence could not be determined because results were strongly assay-dependent.Conclusions
This study reinforces the need to carefully consider assay choice when comparing different studies on the prevalence of anti–Brucella antibodies in pinnipeds and further highlights the need for species- or taxon-specific assay validation for both pathogen and host species. 相似文献378.
Road traffic causes significant amphibian and reptile mortality, which could be mitigated through the installation of road crossing structures that facilitate safe passage, but only if reptiles and amphibians are willing to use them. Through a series of behavioral choice experiments with frogs and turtles, we examined how aperture diameter, substrate type, length, and light permeability influenced individuals’ preferences for specific attributes of crossing structures, and how individuals responded to various heights of barrier fences. Snapping turtles (Chelydra serpentina), green frogs (Rana clamitans), and leopard frogs (Rana pipiens) preferred larger diameter tunnels (>0.5 m) whereas painted turtles (Chrysemys picta) preferred tunnels of intermediate (0.5-0.6 m) diameter. Green frogs preferred soil- and gravel-lined tunnels to concrete- and PVC-lined tunnels. Painted turtles showed non-random choice of different lengths of tunnel, possibly indicating some avoidance of the longest tunnel (9.1 m); although no species preferred to exit via the longest tunnels (9.1 m), members of all four species used such tunnels. Green frogs preferred tunnels with the greatest light permeability. Fences 0.6 m in height were effective barriers to green frogs, leopard frogs, and snapping turtles, whereas 0.3 m fences excluded painted turtles. We conclude that tunnels > 0.5 m in diameter lined with soil or gravel and accompanied by 0.6-0.9 m high guide fencing would best facilitate road crossing for these and likely other frog and turtle species. 相似文献
379.
380.