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61.
Isolation and culture of rabbit primordial germ cells 总被引:2,自引:0,他引:2
Kakegawa R Teramura T Takehara T Anzai M Mitani T Matsumoto K Saeki K Sagawa N Fukuda K Hosoi Y 《The Journal of reproduction and development》2008,54(5):352-357
Primordial germ cells (PGCs) are embryonic precursors of the gametes of adult animals and are considered stem cells of the germline. Since their proliferation in vitro correlates well with the schedule of developmental changes in vivo, they might be interesting research tools for genomic imprinting, germ-cell tumors and fertility. Furthermore, once primordial germ cells are separated and placed on a feeder layer with cytokines, they become cultured pluripotent cell lines called embryonic germ (EG) cells. EG cells share several important characteristics with embryonic stem (ES) cells as they can also contribute to the germ line of chimeras. To investigate the characteristics of PGCs and establish rabbit EG (rEG) cells, we cultured rabbit PGCs (rPGCs) in vitro with various combinations of leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF) and forskolin on inactivated mouse embryonic fibroblast (MEF) feeder layers. The present study found PGC proliferation in early cultures and induction of rEG-like colonies. These cells expressed pluripotent markers, such as alkaline phosphatase activity, OCT-4, Sox-2 and SSEA-1, in the undifferentiated state; however, the cells did not develop into a teratoma when injected into the kidney capsules of SCID mice, although the restricted differentiation potentials to neural cells were determined via embryoid body formation. From these characteristics and further characterization of the germ stem cell markers Vasa, SCP-1 and SCP-3, we suggested that these were hybrid cells with characteristics somewhere between PGC and EG cells. 相似文献
62.
Matsuda F Inoue N Goto Y Maeda A Cheng Y Sakamaki K Manabe N 《The Journal of reproduction and development》2008,54(5):314-320
More than 99% of follicles in mammalian ovaries undergo atresia, but the mechanisms regulating the strict selection process are still unclear. Granulosa cell apoptosis is considered the trigger of follicular atresia, which occurs in advance of the death of an oocyte. Cellular FLICE-like inhibitory protein (cFLIP), a homologue of procaspase-8 (also called FLICE), is an intracellular anti-apoptotic protein. It is expressed in granulosa cells of porcine ovaries, where its levels decreases during follicular atresia. We hypothesized that cFLIP regulates granulosa cell apoptosis by acting as a pro-survival factor. In the present study, to further reveal the function of cFLIP in granulosa cells, we examined the anti-apoptotic mechanism of cFLIP using KGN, a human granulosa tumor cell line. Fas-mediated apoptosis was induced by co-treatment with anti-Fas antibody (CH-11), which acts as an agonist of Fas-ligand, and cycloheximide (CHX). When cFLIP was stably expressed in KGN cells following transfection of an expression vector, the Fas-mediated apoptosis was inhibited. Suppression of cFLIP by small interfering RNA (siRNA) spontaneously induced cell death. Silencing of cFLIP promoted cleavage of procaspase-8, and the cell death caused by cFLIP siRNA was completely blocked by a caspase-8 inhibitor (Z-IETD-FMK), indicating that cFLIP regulates apoptosis in KGN cells by inhibiting cleavage of procaspase-8. In conclusion, cFLIP is an essential pro-survival factor for granulosa cells, and it prevents granulosa cell apoptosis by inhibiting procaspase-8 activation. 相似文献
63.
64.
Hypocretin/orexin is produced exclusively in the dorsal and lateral hypothalamus but its projection is widespread within the brain and plays important roles. In this paper, we review the independent discoveries of the hypocretin/orexin peptides, the neuroanatomy of this system, and the link to the sleep disorder narcolepsy that has led to the idea that this system plays a crucial role in the regulation of sleep and wakefulness. 相似文献
65.
Yuka Maeda Keiko Nishimura Kazuhiro Kurosu Hitoshi Mizuguchi Shigeru Sato Fuminori Terada Shiro Kushibiki 《Animal Science Journal》2019,90(4):523-532
This study aimed to examine the effects of feeding kraft pulp (KP) on the growth performance, feed digestibility, and rumen fermentation of Japanese Black fattening steers. Ten Japanese Black fattening steers (aged 26 months) were randomly divided into control and KP groups. The control group (n = 5) was fed concentrate feed without KP, and the KP group (n = 5) was fed concentrate feed containing 10% KP. Both the groups were provided rice straw as roughage. The experiment was conducted over a period of 12 weeks. There was no significant difference in dry matter intake, daily body weight gain, and nutrient digestibility between both groups. No difference was observed in the ruminal concentrations of volatile fatty acids among the groups. At weeks 8 and 12 after the onset of the experiment, the acetate‐to‐propionate ratio in the ruminal fluid of the KP group was significantly higher than that of the control group. The average daily pH of ruminal fluid and activity of ruminal lipopolysaccharide did not differ between the groups. Our results suggested that the growth performance and feed digestibility in the Japanese Black fattening steers were not influenced by replacing concentrate feed with KP. 相似文献
66.
Kanichi KUSANO Yuhiro ISHIKAWA Kazuhiro SEKI Ryo KUSUNOSE 《Journal of Equine Science》2008,19(2):25-29
Inflammatory airway disease (IAD) is a common cause of poor performance, interruption of
training and premature retirement in racehorses. It is also reported that up to 80% of
horses are affected at some point in the first years of training in UK and Australia.
However, no studies with regard to the information on occurrence of IAD in Japanese
Thoroughbred racehorses have been reported. To investigate the occurrence and the
characteristics of IAD, epidemic research including endoscopic examination of the airway
tract and trachea wash was conducted for Thoroughbred racehorses presenting coughs or poor
performance which airway tract disease was suspected stalled in training facility managed
by Japan Racing Association. Fifty-six out of 76 Thoroughbred racehorses (73.7%)
presenting coughing or poor performance were diagnosed as IAD. Mean incidence rate of IAD
was 0.3% and it has been confirmed that constant number of IAD exists in Japan. Up to
35.7% of IAD horses showed upper airway abnormalities in some extent. There was a trend
for IAD horses to use wood shavings for bedding and fed hay from the ground compared with
the control group. Therefore, improvement of stabling environment may aid in preventing
IAD. This study demonstrated that Japanese Thoroughbred racehorses are affected by IAD
likewise other countries as well as demonstrated the characteristics of IAD which may
contribute to the clarification of the pathogenesis of IAD. 相似文献
67.
Thanh Quang Dang‐Nguyen Hiep Thi Nguyen Tamas Somfai David Wells Nguyen Thi Men Nguyen Viet‐Linh Junko Noguchi Hiroyuki Kaneko Kazuhiro Kikuchi Takashi Nagai 《Animal Science Journal》2018,89(6):880-887
We investigated whether high‐quality in vitro matured (IVM) oocytes can be distinguished from poor ones based on the morphological changes after treatment with hyperosmotic medium containing 0.2 mol/L sucrose in pigs. We hypothesize that IVM oocytes maintaining round shape have higher quality than mis‐shapened oocytes following dehydration. Oocyte quality was verified by determining embryonic developmental competence using in vitro fertilization, nuclear transfer and parthenogenetic activation. In all cases, the round oocytes had greater (p < .05) developmental competence than that of mis‐shapened oocytes in terms of blastocyst rate and total cell number in blastocysts obtained after 6 days of in vitro culture. We also confirm that round aged oocytes are higher in quality than mis‐shapened aged oocytes. In an attempt to find out why high‐quality oocytes maintain a round shape whereas poorer oocytes become mis‐shapened following sucrose treatment, we examined the arrangement of actin microfilaments and microtubules. Abnormal organization of these cytoskeletal components was higher (p < .05) in mis‐shapened oocytes compared to round oocytes after 52 hr of IVM. In conclusion, sucrose treatment helps selection of high‐quality oocytes, including aged oocytes, in pigs. Abnormal cytoskeleton arrangements partly explain for low developmental competence of mis‐shapened oocytes. 相似文献
68.
Saeid Moharramipour Kazuyoshi Takeda Kazuhiro Sato Hideya Yoshida Hisaaki Tsumuki 《Euphytica》1999,106(2):181-185
The inheritance of gramine indole alkaloid was studied in F1 and F2 generations derived from crosses between wild ( Hordeum
vulgare subsp. spontaneum) and cultivated ( H. vulgare subsp. vulgare) barley at adult stage in the field. The means of gramine
content were very low in F1s and F2s in April and May. The ratio of progeny containing gramine to those without gramine (near
zero or undetectable) fit a mono-genic or di-genic model in F2 generation. However, the content of gramine might be controlled
by minor genes in the gramine-containing plants. The direction of dominance was toward lower gramine content. The averages
of dominance ( h/d) in F1 and F2 ranged from partial to complete. Broad-sense heritabilities were high (0.70 to 0.77). The
usefulness of hybrids for breeding aphid resistance and possibility increasing palatability of grazing pasture for sheep and
cattle is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
69.
The external layer of a teleost fish scale is composed of type I collagen, an amorphous matrix substance and hydroxyapatite
crystals. Calcification of this layer can be inhibited in the scale-regenerating process under calcium- and phosphate-deficient
(CaDPD) conditions, and can be facilitated by incubation in physiological saline. The aim of this study was to evaluate this
model of calcification using histological and quantitative analysis in order to promote further understanding of the mechanism
of calcification in fish scales. We found that the external layer of the scales produced under CaDPD conditions contained
more densely aligned collagen fibrils with a small amount of the amorphous matrix substance. The CaDPD scale contained only
one-third of the amount of calcium and phosphate present in the control fish. After 4 hours of incubation, a two- to threefold
increase in calcium content and a 1.5-fold increase in phosphate content were observed. Calcification proceeded in the external
layer, and mineral deposits grew only in the electron-dense matrix substance. We conclude that this model would be suitable
for studying the early process of fish scale calcification that occurs in the noncollagenous substance. The electron-dense
substance may contain key molecules that promote calcification. 相似文献
70.
Kazuhiro Shiozaki Momo Shiozaki Junko Masuda Akiko Yamauchi Shuichi Ohwada Toshiki Nakano Toshiyasu Yamaguchi Tadao Saito Koji Muramoto Minoru Sato 《Fisheries Science》2010,76(5):865-872
Angiotensin-I-converting enzyme (ACE) plays a crucial role in the crisis of hypertension. Some peptides that originate from
protease hydrolysates are known to suppress ACE activity in vitro and in vivo. Here, we investigated whether trypsin hydrolysate
of oyster Crassostrea gigas showed hypotensive activity and ACE inhibition. The hydrolysate significantly suppressed systolic blood pressure and ACE
activity in spontaneously hypertensive rats following a one-shot oral administration and a long-term feeding experiment lasting
9 weeks. Each hydrolysate from oyster tissue showed ACE inhibitory activity, indicating the hypotensive effect was due to
synergism. One potent ACE inhibitory peptide, Asp-Leu-Thr-Asp-Tyr, was identified from the hydrolysate of the striate muscle,
and the peptide exhibited hypotensive activity in vivo. Protease digestion analysis suggested that Asp-Tyr could be the real
effector of this penta-peptide in vivo. 相似文献