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1.
生殖细胞移植是指将供体的生殖细胞移植到同种或异种受体体内,供体生殖细胞嵌合到受体性腺,经过增殖、分化并最终发育为功能性配子的过程。作为辅助生殖技术,它不仅为珍稀濒危动物的繁育和保护提供了新途径,同时也为生殖干细胞的功能研究提供了有效手段。鱼类生殖细胞移植研究首先在模式鱼类斑马鱼中开展,经过十多年的发展,取得了一系列突破性的进展:主要包括先后建立了以胚胎、仔鱼和成鱼为受体的生殖细胞移植体系,精原和卵原干细胞的发现拓宽了供体生殖细胞的选择,受体的选择与制备方法的完善。该技术在缩短鱼类性成熟周期、性控育种、珍稀濒危鱼类保护等方面具有巨大的应用前景,已成功在多种淡水和海水鱼类中开展了研究和应用。本文结合作者的研究实践和经验,系统地梳理和总结了鱼类生殖细胞移植的研究进展,指出了该技术实践应用的关键问题,并探讨了其应用前景。 相似文献
2.
Takafumi SUZUKI Naohito NISHII Satoshi TAKASHIMA Tatsuya MATSUBARA Atsushi IWASAWA Hirofumi TAKEUCHI Kohei TAHARA Tatsuyuki HACHISU Hitoshi KITAGAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1379-1383
Polyclonal immunoglobulin (Ig) G autoantibodies against insulin have been
identified in sera of healthy cats. We purified and fractionated insulin-binding IgGs from
cat sera by affinity chromatography and analyzed affinity of insulin-binding IgGs for
insulin and their epitopes. Following the passing of fraction A, which did not bind to
insulin, insulin-binding IgGs were eluted into two fractions, B and C, by affinity
chromatography using a column fixed with bovine insulin. Dissociation constant (KD) values
between insulin-binding IgGs and insulin, determined by surface plasmon resonance analysis
(Biacore™system), were 1.64e−4 M for fraction B (low affinity IgGs) and
2e−5 M for fraction C (high affinity IgGs). Epitope analysis was conducted
using 16 peptide fragments synthesized in concord with the amino acid sequence of feline
insulin by an enzyme-linked immunosorbent assay. Fractions B and C showed higher
absorbance (affinity) of the peptide fragment of 10 amino acid residues at the
carboxyl-terminal of the B chain (peptide No. 19), followed by peptide fragments of 6 to
15 amino acid residues of the B chain (peptide No. 8). Fraction C showed a higher
absorbance to 7 to 16 amino acid residues of the B chain (peptide No. 5) compared with the
absorbance of fraction B. Polyclonal insulin-binding IgGs may form a macromolecule complex
with insulin through the multiple affinity sites of IgG molecules. Feline insulin-binding
IgGs are multifocal and may be composed of multiple IgG components and insulin. 相似文献
3.
ABSTRACT: Three diets supplemented with taurine, β-alanine andGABA and a control diet were fed to juvenile and fingerling Japaneseflounder to investigate the effects of the diets on growth and metabolicchanges of free amino acids in whole body and tissues. In experimentI, three diets supplemented with 1% each of taurine, β-alanineand GABA and a control diet were fed to juvenile Japanese flounderwith an initial mean body weight of 0.4 g for 4 weeks at20°C. In experiment II, the taurine-supplemented diet anda control diet were fed to fingerling Japanese flounder with an initialmean body weight of 15 g for 4 weeks at 20°C.Only supplementation of taurine in the diet of juvenile flounderimproved their growth performance in experiment I, but fingerlinggrowth performance of experiment II was not significantly relatedto taurine supplementation in the experimental diet. These resultssuggest that there is a greater requirement for taurine for thegrowth of juvenile Japanese flounder than fingerling Japanese flounder. 相似文献
4.
ABSTRACT: In order to simplify the food chain in a closed ecological recirculating aquaculture system, raw Spirulina platensis cultivated in 50-L photobioreactors were fed to tilapia Oreochromis niloticus as a uni-feed from the onset of exogenous feeding. The feasibility of using tilapia grown on raw Spirulina (body weight: 155.4 ± 3.9 g, standard length: 16.2 ± 0.2 cm; n = 3) was investigated for 30 weeks for sashimi (sliced raw meat). Some of the rheological properties of the flesh were measured to clarify the obtained results of sensory evaluations of texture and fatness. The elastic modulus of flesh of the Spirulina -fed fish was significantly higher than that of the control fish (body weight: 168.9 ± 5.8 g, standard length: 17.8 ± 0.5 cm; n = 3) that were fed commercial diets. In addition, the viscosity of the flesh of the Spirulina -fed fish was significantly lower than that of the control fish. There was no significant difference in the rupture strength between the two treatments. The rheological parameters in the muscle were found to coincide with the results of the sensory assessment. These results suggest that tilapia fed solely on raw Spirulina have a high flesh quality that is suitable for sashimi. The muscle lipid of the raw Spirulina -fed fish had lower levels of non-polar lipids such as triglycerides and partial glycerides, but higher levels of polar lipids such as phosphatidylcholine and phosphatidylethanolamine. The fatty acid profile of the raw Spirulina -fed fish muscle, especially in the polar lipid fraction, was characterized by an abundance of Σn-6 highly unsaturated fatty acids (20:3n-6, 20:4n-6, 22:4n-6, 22:5n-6). 相似文献
5.
Optimal dietary taurine level for growth of juvenile Japanese flounder Paralichthys olivaceus 总被引:5,自引:0,他引:5
GWANG-Sic PARK TOSHIO TAKEUCHI MASAHITO YOKOYAMA TADAHISA SEIKAI 《Fisheries Science》2002,68(4):824-829
The requirement for taurine in juvenile Japanese flounder Paralichthys olivaceus was determined by feeding diets containing various levels of taurine and cystine. Test diets supplemented with 0.5, 1.0 and 1.5% of taurine or with 0.5, 1.0 and 1.5% of L -cystine were prepared. The basal diet contained 55% protein from white fish meal. These diets were fed to juvenile Japanese flounder with an initial mean bodyweight of 0.9 g (total length (TL) 48 mm) for 5 weeks. Approximately 1.4% taurine content in the diet was required for optimum growth of juvenile flounder. A positive linear relationship was noted between the content of taurine accumulated in the muscle, liver and brain and the level of taurine in the diet. However, there was no increased taurine content in tissues of fish fed the cystine-supplemented diet. In contrast, the fish fed control and cystine-supplemented diets showed higher contents of cystathionine in the tissues. The concentration of cystathionine in tissues rapidly decreased with an increase of taurine in the diet. It was also observed that for each of the dietary groups, a trace amount of taurine was excreted. These results suggest that the taurine content in the diet affects the sulfur amino acid metabolism of juvenile Japanese flounder, and indicate that juvenile flounder are unable to biosynthesize taurine from cystine. 相似文献
6.
7.
Shiro KUNINAGA Donald E CARLING Toru TAKEUCHI Ryozo YOKOSAWA 《Journal of General Plant Pathology》2000,66(1):2-11
Genetic diversity among 51 isolates of Rhizoctonia solani AG-3, representing potato and tobacco populations, was inferred from the sequences of the internal transcribed spacer (ITS)
and 5.8S ribosomal RNA (rRNA) gene. The 5.8S rDNA sequence was completely conserved not only in AG-3, but across all the AG
isolates examined, whereas the rDNA-ITS sequence was found to be variable among the isolates. The nucleotide sequence similarity
in the ITS 1 region was high (96-100%) for isolates within each of the two populations, but was 91-92% for isolates from different
populations. The AG-3 isolates had 56 to 91% sequence similarities in the ITS 1 region with R. solani isolates of the other AGs. Phylogenetic analysis based on the ITS-5.8S rDNA sequence data indicated that the different populations
in AG-3 are distantly related to each other. Genetic divergence between the two populations was also supported by the results
of DNA-DNA hybridization studies. This study suggests that AG-3 consists of two genetically isolated groups corresponding
to separate subgroups: AG-3 PT (potato type) and AG-3 TB (tobacco type). Specific primer sets for the detection of the two
AG-3 subgroups were developed from the aligned rDNA-ITS sequences.
Received 22 April 1999/ Accepted in revised form 2 July 1999 相似文献
8.
Shigeharu TAKEUCHI Yasufumi HIKICHI Yoichi KAWADA Tetsuro OKUNO 《Journal of General Plant Pathology》2000,66(2):153-158
A method for detecting tobamoviruses from field soils was developed using non-precoated indirect enzyme-linked immunosorbent
assay (Id-ELISA). Absorbance values in Id-ELISA were relatively low after directly applying Pepper mild mottle virus (PMMoV)-infested soil extract. However, heat treating the soil extract before application greatly enhanced the absorbance
values. The heat treatment was essential for the Id-ELISA detection of tobamoviruses from infested soil, although the efficiency
of virus recovery varied depending on the properties of soil. The number of local lesions in the infectivity assay was consistent
with the absorbance values in Id-ELISA. Moreover, the absorbance values in Id-ELISA were correlated with the incidence of
soil transmission of PMMoV. Thus, Id-ELISA combined with heat treatment is a practical technique for the diagnosis of infestation
with Tobamovirus in field soils, Gray Lowland soil and Sand-dune Regosol.
Received 4 October 1999/ Accepted in revised form 9 December 1999 相似文献
9.
Akihito TAKAHASHI Ajalli RAHIM Miki TAKEUCHI Emiko FUKUI Midori YOSHIZAWA Kuniaki MUKAI Makoto SUEMATSU Hidetoshi HASUWA Masaru OKABE Hiromichi MATSUMOTO 《The Journal of reproduction and development》2016,62(1):43-49
Tubulointerstitial nephritis antigen-like 1 (Tinagl1, also known as adrenocortical zonation factor 1 [AZ-1]
or lipocalin 7) is a matricellular protein. Previously, we demonstrated that Tinagl1 expression was restricted
to extraembryonic regions during the postimplantation period and detected marked expression in mouse
Reichert’s membranes. In uteri, Tinagl1 is markedly expressed in the decidual endometrium during the
postimplantation period, suggesting that it plays a physical and physiological role in embryo development
and/or decidualization of the uterine endometrium during pregnancy. In the present study, in order to
determine the role of Tinagl1 during embryonic development and pregnancy, we generated
Tinagl1-deficient mice. Although Tinagl1–/– embryos were not
lethal during development to term, homologous matings of Tinagl1–/– females and
Tinagl1–/– males showed impaired fertility during pregnancy, including failure
to carry pregnancy to term and perinatal lethality. To examine ovarian function, ovulation was induced with
equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); the number of ovulated oocytes did
not differ between Tinagl1–/– and Tinagl1flox/flox.
In vitro fertilization followed by embryo culture also demonstrated the normal
developmental potential of Tinagl1-null embryos during the preimplantation period. Our
results demonstrate that Tinagl1 deficiency affects female mice and results in subfertility phenotypes, and
they suggest that although the potential of Tinagl1–/– oocytes is normal, Tinagl1
is related to fertility in adult females but is not essential for either fertilization or preimplantation
development in vitro. 相似文献
10.
Yoshie MANABE Makoto TOCHIGI Akiyoshi MORIWAKI Sakae TAKEUCHI Sumio TAKAHASHI 《The Journal of reproduction and development》2013,59(4):398-404
Reproductive functions decline with the onset of diabetes in female mice. Diabetic mice
have smaller uteri with an underdeveloped endometrium, suggesting diminished
estrogen-induced growth. We aimed to clarify the changes in the estrous cycle and in
insulin-like growth factor 1 (IGF1) expression in the uteri of streptozotocin
(STZ)-treated diabetic mice, because IGF1 is one of the main growth factors involved in
estrogen-induced uterine growth. ICR female mice were intraperitoneally administered STZ
(10 mg/100 g BW), and blood glucose levels were determined. Mice with blood glucose levels
> 200 mg/dl were classified as diabetic mice. The onset of diabetes was associated with
acyclic estrous cycles. Diabetes was also induced with STZ in ovariectomized mice. Uterine
Igf1 mRNA levels were reduced in ovariectomized STZ-treated diabetic
mice. Estrogen is known to stimulate Igf1 mRNA expression in the uterus,
but estrogen action was abolished in the uteri of STZ-treated diabetic mice. mRNA
expressions of estrogen receptor α (ERα) and steroid hormone receptor coactivators
(SRC-1/Ncoa1, SRC-2/Ncoa2,
SRC-3/Ncoa3 and CBP/p300/Crebbp) were reduced in the
uteri of ovariectomized STZ-treated diabetic mice. The present study demonstrates that
diabetes induces a decline in female reproductive functions in mice. Igf1
expression in ovariectomized diabetic female mice was decreased, and decreased
responsiveness to estrogen in the uteri of diabetic mice is probably associated with a
reduction in ERα and steroid receptor coactivator mRNA expression. 相似文献