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41.
42.
The present study was conducted to examine the fertility of ewes inseminated intrauterinally with frozen semen using semen extender containing either egg yolk or bovine serum albumin (BSA). Sixty Suffolk and cross-bred ewes were treated with controlled internal drug release (CIDR) devices during the non-breeding season (July 2006). A CIDR was inserted into the vagina for 12 days and an intramuscular injection of 500 IU equine chorionic gonadotropin was administered one day before its removal. Ejaculates from a suffolk ram were diluted with a Tris-based extender containing either 15% (v/v) egg yolk or 10% (w/v) BSA, and the diluted semen was frozen in 0.25 ml straws. A fixed-time intrauterine artificial insemination (AI) was performed 43-47 h after CIDR removal, regardless of incidence of estrus. There was no significant difference in pregnancy rates at 60 days after AI between the extenders containing egg yolk (66.7%, 20/30 animals) or BSA (65.5%, 19/29 animals). Furthermore, there were no significant difference in the lambing rates (66.7% and 62.1%) and prolificacy (1.25 and 1.56) between the two semen extenders. The present study indicates that a semi-defined semen extender containing 10% BSA produces fertility after intrauterine AI that is similar to that achieved with semen extender containing egg yolk. 相似文献
43.
Tanaka S Aso H Miyazawa K Nagai Y Watanabe K Ohwada S Kobayashi J Yamaguchi T 《Veterinary immunology and immunopathology》2007,118(1-2):84-91
The distinct patterns of cytokine expression in CD4+ and CD8+ T cells are well understood in mice and humans. However, little information is available about cytokine expression in bovine CD4+ and CD8+ T cells. In this study, mRNA expression of 19 different cytokines was analyzed in CD4+ and CD8+ T cells of calves with or without Concanavalin A (Con A) stimulation. CD4+ and CD8+ T cell populations were enriched to 98% purity by positive selection using magnetic cell sorting (MACS). CD4+ T cells spontaneously expressed the mRNAs of interleukin-1alpha (IL-1alpha), IL-1beta, IL-2, IL-6, IL-7, IL-8, IL-10, IL-18, IFN-gamma, TNF-alpha, TNF-beta and TGF-beta, and augmented the mRNA expression of IL-10, IFN-gamma and TNF-beta after Con A stimulation. The mRNAs of IL-3, IL-4, IL-5, IL-13 and GM-CSF were newly expressed in Con A-stimulated CD4+ T cells. CD8+ T cells displayed spontaneous mRNA expression of IL-6, IL-18, TNF-alpha, TNF-beta and TGF-beta, and newly expressed the mRNA of IL-2, IL-7, interferon-gamma (IFN-gamma) and GM-CSF after Con A stimulation. It was found that CD4+ T cells expressed the mRNA of 17 cytokines except for IL-12 and IL-15, while CD8+ T cells expressed only the mRNA of 9 cytokines after Con A stimulation. The profile of cytokine mRNA expression was substantially different in the CD4+ and CD8+ T cells of calves, indicating that CD4+ T cells can be distinguished from CD8+ T cells by the cytokine gene expression of IL-1alpha, IL-1beta, IL-3, IL-4, IL-5, IL-8, IL-10 and IL-13. Differential cytokine expression between CD4+ and CD8+ T cells serve to interpret an individual function of T cell subsets in the immune system of calves. 相似文献
44.
Kanaya T Aso H Miyazawa K Kido T Minashima T Watanabe K Ohwada S Kitazawa H Rose MT Yamaguchi T 《Research in veterinary science》2007,82(2):141-149
M cells play a central role in the initiation of mucosal immune responses. However, a primary source of difficulty for investigations of this is the lack of an available specific marker for bovine M cells. As M cells possess irregular and short microvilli, we investigated the distribution and localization of the microvillar proteins actin and villin by immunohistochemistry of the gut of calves. In ileum of the calf, actin and villin were clearly and continuously immunostained in the brush border of the villous epithelia, however, discontinuous immunostaining with patches of no staining were observed in follicle-associated epithelium (FAE). Electron microscopy revealed that M cells had irregular microvilli and lacked the typical brush border, and it was inferred that these patches of no staining might be the intercellular crevices of M cells. As the microvilli of M cells were very sparse, there were several areas of weak immunostaining in calf jejunal FAE. These results suggest that M cells in calf FAE are detectable by the absence of staining for actin and villin. 相似文献
45.
Mami UEMURA Hitomi IGARASHI Aisa OZAWA Naoki TSUNEKAWA Masamichi KUROHMARU Masami KANAI-AZUMA Yoshiakira KANAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):587-591
In early embryogenesis, the posteroventral foregut endoderm gives rise to the
budding endodermal organs including the liver, ventral pancreas and gallbladder during
early somitogenesis. Despite the detailed fate maps of the liver and pancreatic
progenitors in the mouse foregut endoderm, the exact location of the gallbladder
progenitors remains unclear. In this study, we performed a DiI fate-mapping analysis using
whole-embryo cultures of mouse early somite-stage embryos. Here, we show that the majority
of gallbladder progenitors in 9–11-somite-stage embryos are located in the lateral-most
domain of the foregut endoderm at the first intersomite junction level along the
anteroposterior axis. This definition of their location highlights a novel entry point to
understanding of the molecular mechanisms of initial specification of the gallbladder. 相似文献
46.
N-beta-Alanyldopamine is the major tyrosine metabolite in the hemolymph and cuticle during pupal tanning in the tobacco hornworm, Manduca sexta L. Its concentration in hemolymph increases over 800-fold above larval levels by the start of tanning and decreases as the pupal cuticle darkens and hardens. It is a major catechol in species representing several insect orders and is the preferred substrate for pupal cuticular o-diphenol oxidase. In insects, N-beta-alanyldopamine appears to be the main precursor for tanning chemicals at certain developmental stages. 相似文献
47.
Hidekazu Yamada Yumei Kang Tomonori Aso Hiroshi Uesugi Tomokazu Fujimura Koyo Yonebayashi 《Soil Science and Plant Nutrition》2013,59(3):385-391
The chemical forms of selenium (Se) in soils derived from different parent rocks, and the stability of Se species in soils were investigated. Around 40% of the total Se occurred as organic Se on the average. Total selenite content was higher than that of total selenate. The content of organic Se decreased with heating of the soils at high temperatures, and most of it disappeared at heating temperatures above 500°C. However, the results of incubation experiments indicated that Se species were stable in soil, and that their chemical forms did not change appreciably with the variation of soil conditions. In soluble Se, organic Se accounted for about 50%, and in contrast to the total Se, the selenate content was higher than that of selenite. 相似文献
48.
Leptin is thought to be not only a satiety factor but also a stimulator of angiogenesis. We examined leptin, PPARγ2, and vascular endothelial growth factor (VEGF) expression in bovine intramuscular preadipocyte (BIP) cells during proliferation. The cells were seeded at 0.85 × 104 cells/cm2 and collected every day until the fifth day after passage. Leptin mRNA was present in the cells between days 2 and 4, as indicated by RT-PCR analysis. Western blot analysis showed a band for leptin at approximately 16 kDa on all of the days during growth, and the cytoplasmic concentration of leptin was highest on day 2 and decreased gradually thereafter. A PPARγ2 band at approximately 54 kDa was also observed on all days. The concentration was highest on day 2 and decreased thereafter, which is similar to the expression pattern of leptin. In constant, the expression level of VEGF protein did not change while in culture. We have demonstrated that BIP cells can synthesize both leptin and PPARγ2, with maximal synthesis occurring during maximal proliferation. Given the role of leptin in angiogenesis, we speculate that leptin is involved in the neovascularization of adipose tissue, because new organization of adipose tissue requires the growth of new blood vessels. 相似文献
49.
Tomoaki Tochitani Izumi Matsumoto Kohei Hoshino Kaoru Toyosawa Mami Kouchi Takatoshi Koujitani Juki Kimura Hitoshi Funabashi 《Journal of toxicologic pathology》2013,26(2):187-191
The common marmoset (Callithrix
jacchus) is now widely used in various
research fields, including toxicology. However,
information about the background pathology of this
species is scarce. Here, we report a case of
rhabdomyosarcoma that spontaneously occurred in a
common marmoset. A 44-month-old male common
marmoset was euthanized due to bilateral hind limb
paralysis. At necropsy, a 2×2×5-cm intramuscular
mass was observed in the lower right back.
Histologically, the mass was mainly composed of
interlacing bundles of spindle-shaped tumor cells.
Immunohistochemically, the tumor cells were
positive for myogenin, desmin, vimentin and
alpha-smooth muscle actin. Ultrastructurally, the
tumor cells contained bundles of myofilaments with
Z-band-like structures. Thus, the tumor was
diagnosed as a rhabdomyosarcoma. To our knowledge,
this is the first report of spontaneous
rhabdomyosarcoma that was definitely diagnosed in
the common marmoset. 相似文献
50.
Mami OIKAWA Shogo MATOBA Kimiko INOUE Satoshi KAMIMURA Michiko HIROSE Narumi OGONUKI Hirosuke SHIURA Michihiko SUGIMOTO Kuniya ABE Fumitoshi ISHINO Atsuo OGURA 《The Journal of reproduction and development》2013,59(3):231-237
In mice, one of the major epigenetic errors associated with somatic cell nuclear
transfer (SCNT) is ectopic expression of Xist during the preimplantation
period in both sexes. We found that this aberrant Xist expression could
be impeded by deletion of Xist from the putative active X chromosome in
donor cells. In male clones, it was also found that prior injection of
Xist-specific siRNA could significantly improve the postimplantation
development of cloned embryos as a result of a significant repression of
Xist at the morula stage. In this study, we examined whether the same
knockdown strategy could work as well in female SCNT-derived embryos. Embryos were
reconstructed with cumulus cell nuclei and injected with Xist-specific
siRNA at 6–7 h after oocyte activation. RNA FISH analysis revealed that siRNA treatment
successfully repressed Xist RNA at the morula stage, as shown by the
significant decrease in the number of cloud-type Xist signals in the
blastomere nuclei. However, blastomeres with different sizes (from “pinpoint” to “cloud”)
and numbers of Xist RNA signals remained within single embryos. After
implantation, the dysregulated Xist expression was normalized
autonomously, as in male clones, to a state of monoallelic expression in both embryonic
and extraembryonic tissues. However, at term there was no significant improvement in the
survival of the siRNA-injected cloned embryos. Thus, siRNA injection was largely effective
in repressing the Xist overexpression in female cloned embryos but failed
to rescue them, probably because of an inability to mimic consistent monoallelic
Xist expression in these embryos. This could only be achieved in female
embryos by applying a gene knockout strategy rather than an siRNA approach. 相似文献