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61.
We previously identified a novel gonad-specific expression gene (Gse) and investigated its expression during gametogenesis in the mouse testis and ovary. In this study, we generated a polyclonal antibody to GSE protein and determined the profiles of the protein's expression in germ cells and preimplantation embryos in detail using immunocytochemical and immunofluorescence staining. In a Western blot analysis, the anti-GSE antibody recognized long and short isoforms (approximately 27.6 kDa and 23.1 kDa) of the protein in the mouse testis and the long isoform in the ovary. In the mouse testis, GSE protein was expressed in spermatocytes I in the pachytene stage, round spermatids, and elongated spermatids. In the mouse ovary, the protein was located in the cytoplasm and nucleus of all oocytes regardless of the stage of the ovarian follicles. In preimplantation embryos from the pronuclear to blastocyst stage, however, GSE protein was mainly detected in the nuclei of cells. At the blastocyst stage, the protein was confirmed to have accumulated in the inner cell mass (ICM), whereas it had mostly disappeared from the trophectoderm (TE). These findings suggest that GSE protein may play a role in the establishment of nuclear totipotency and may be associated with early lineage specification.  相似文献   
62.
The objective of this study was to examine the effect of postactivation treatment with latrunculin A (LatA), an actin polymerization inhibitor, on in vitro and in vivo development of somatic cell nuclear transfer (SCNT) embryos derived from kidney fibroblasts of an aged Clawn miniature boar (12 years old). After electric activation, SCNT embryos were treated with 0, 0.5 or 1 μM LatA and cultured in vitro. The rate of blastocyst formation was significantly higher (P<0.05) in SCNT embryos treated with 0.5 μM LatA (38%) than those in control (14%). When cloned embryos treated with 0.5 μM LatA were transferred into the oviducts of two recipient miniature gilts to assess their development in vivo, both recipients became pregnant; one maintained pregnancy to term, and a live piglet (weighing 220 g) was delivered by Caesarean section. The results of this study indicated that the postactivation treatment with LatA was effective in improving in vitro developmental capacity of SCNT miniature pig embryos derived from kidney fibroblasts of an aged animal and that miniature pig cloned embryos treated with LatA had the ability to develop to term.  相似文献   
63.
Although the importance of carbohydrate recognition by sperm during egg zona pellucida binding has been widely reported, the sperm molecular species that recognize the carbohydrates are poorly characterized. Our previous cytochemical study indicated that two kinds of carbohydrate-binding proteins are expressed on porcine sperm heads-one recognizes N-acetyllactosamine (Galβ1-4GlcNAc-), and the other recognizes the Lewis X structure (Galβ1-4(Fucα1-3)GlcNAc-). For this report, we used proteomic techniques to characterize the sperm proteins that bind N-acetyllactosamine. Porcine sperm plasma membrane was solubilized with a detergent solution and subjected to sequential chromatography with dextran sulfate agarose, affinity, and hydroxyapatite, and the binding activities in the eluates were monitored by a solid-phase binding assay. The tryptic peptides of two proteins most likely associated with the binding activities were subjected to tandem mass spectrometry sequencing. A subsequent database search identified one of the two proteins as predicted disintegrin and metalloprotease domain-containing protein 20-like (XP_003128672). The other protein was identified as disintegrin and metalloprotease domain-containing protein 5 (AB613817) by database searches for homologous amino acid sequences, cDNA cloning, nucleotide sequencing and nucleotide database searches. Furthermore, two-dimensional blue native/SDS-PAGE demonstrated that they formed a variety of non-covalent complexes. Therefore, these ADAM complexes probably are responsible for the N-acetyllactosamine-binding activity. An affinity-purified fraction containing these ADAM complexes showed zona pellucida-binding activity, though the activity was relatively weak, and the presence of another zona pellucida-binding protein that probably works in concert with these ADAM complexes was suggested. Immunofluorescence testing suggested that ADAM20-like was localized on the anterior part of the sperm plasma membrane.  相似文献   
64.
To develop a simple procedure for estimating glomerular filtration rate (GFR) in calves, a three-sample method using iodixanol was first compared to that using the standard agent inulin. Iodixanol and inulin were co-administered intravenously to calves at 40 mg I/kg and 40 mg/kg, respectively, and blood was collected 30, 60, 120, and 180 min later. Serum iodixanol and inulin concentrations were separately determined by high performance liquid chromatography and colorimetry. Serum urea nitrogen (UN) and creatinine concentrations were also measured. GFR estimated by iodixanol was consistent with that using inulin in clinically healthy calves. Based on GFR estimations in healthy calves and those renal-loaded with iodixanol, it was found that the serum creatinine concentrations became elevated when GFR decreased to 60% of the reference value. In contrast, serum UN concentrations fluctuated widely, presumably due to extra-renal factors. When GFR was estimated using the three-sample method and compared with the single-blood-sample method, 62/69 (90%) of samples tested were within the agreement plots. The results demonstrated that the single-blood-sample method using iodixanol may be useful in monitoring GFR in calves.  相似文献   
65.
A series of imidazole-1-carboxylates was prepared by reacting various alcohols with trichloromethyl chloroformate and imidazole or N,N'-carbonyl-diimidazole. They were tested for fungitoxic activity in vitro against two phytopathogenic fungi, Botrytis cinerea (grey mould) and Gibberella fujikuroi, and for preventive efficacy against grey mould on cucumber leaves. 1-(4-Substituted phenoxymethyl)-2,2-dimethylpropylimidazole-1-carboxylates showed excellent in-vitro activity against B. cinerea, and moderate activity against G. fujikuroi, and some of them also effectively controlled grey mould in vivo. A 1H-1,2,4-triazole derivative corresponding to an imidazole derivative did not have any activity, while a thiocarboxylate corresponding to an imidazole carboxylate showed excellent activity against both B. cinerea and G. fujikuroi.  相似文献   
66.
This report describes the morphological and immunohistochemical characteristics of an adrenocortical carcinoma with distant metastasis in a Sprague-Dawley rat. Macroscopically, a single large mass was observed in the adrenal gland, and multiple nodules were noted in the lung, liver and thyroid. Histologically, the adrenal tumor consisted of a solid growth of eosinophilic round cells with nuclear atypia. Vascular invasion was present, and multiple metastatic lesions were also observed in the lungs, liver, and mediastinal lymph nodes. Immunohistochemically, the nuclei of these tumor cells were positive for Steroidogenic Factor-1 (SF-1). In the thyroid, tumor cells histologically resembling adrenal cells were immunohistochemically negative for SF-1 but positive for calcitonin; thus the lesion was diagnosed as thyroid C-cell carcinoma. From these results, the present case was diagnosed as adrenocortical carcinoma with distant metastases. SF-1 could be a valuable marker for the differential diagnosis of adrenocortical tumors versus other endocrine tumors such as C-cell carcinoma.  相似文献   
67.
68.
Isolation and culture of rabbit primordial germ cells   总被引:2,自引:0,他引:2  
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   
69.
We stored plug seedlings of tomato (Solanum lycopersicum L. cv. Momotaro) under limited fertilisation (LF) for 12 weeks, and evaluated growth and development during storage and after planting. Seedlings in the LF treatment were grown in substrate containing starter fertiliser and irrigated with water. Controls (CT) were irrigated with nutrient solution. Stem growth, leaf growth, and biomass accumulation slowed or ceased during storage of LF seedlings, while CT seedlings showed increases in these parameters. At 2 weeks after planting, the stem length of LF seedlings was shorter than that of CT seedlings, but the two seedling types had similar numbers of leaves. At harvest, LF and CT plants had similar numbers of leaves under the fruit trusses, but the trusses formed at lower heights in LF than in CT seedlings. LF and CT plants produced similar numbers of fruits and similar yields from the first to third trusses. These results indicate that tomato plug seedlings can be stored for more than 2 months under LF.  相似文献   
70.
Human epigenetic studies suggest that consumption of seaweed prevents mammary cancer, which possibly is explained by iodine daily intake. In this study, we evaluated the efficacy of dietary intake of iodine‐enriched eggs on mammary tumor incidence caused by the expression of activated type ErbB2. Female transgenic mice were divided into three groups, and fed a basic diet, a diet supplemented with ordinary eggs, or with iodine‐enriched eggs. The number of mammary tumors greater than 5 mm in diameter was recorded in mice at 6 months of age. We report that the average number of mammary tumors per mouse was significantly lower in the iodine‐enriched egg‐added diet group than in either the basic diet or ordinary egg diet groups. These results indicate that iodine intake through livestock‐derived products can reduce the incidence of mammary cancers caused by the expression of activated type ErbB2.  相似文献   
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