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81.
The positive effect of strontium ions (Sr2+) on sperm motility, capacitation and acrosome reaction has been demonstrated in the mouse, human, guinea pig and hamster. In the present study, we have evaluated the effect of Sr2+ on the viability and acrosome morphology of boar spermatozoa, and on the fertilization and development after the microinjection of Sr(2+)-treated spermatozoa into porcine oocytes. Before incubation, 79% of spermatozoa were classified as propidium iodide (PI)-negative (live) using the LIVE/DEAD Sperm Viability Kit. After incubation with strontium chloride (SrCl2), 39% (0 mM; no divalent cations), 25% (1.9 mM) and 24% (7.5 mM) of them were classified as PI-negative. The proportion of spermatozoa that had initiated the acrosome reaction was higher in Sr(2+)-containing medium than in Sr(2+)-free medium, when assessed by electron microscopy. There was no significant difference in percentage of spermatozoa initiating the acrosome reaction between Sr2+-treated groups (1.9 mM: 22%, 7.5 mM: 33%, p>0.05). After the microinjection of spermatozoa incubated with SrCl2, 67% (1.9 mM) and 61% (7.5 mM) of injected oocytes were successfully fertilized, and then 43% (1.9 mM) and 41% (7.5 mM) contained a fully decondensed sperm head. Sham-injected oocytes were significantly activated at a lower rate than Sr(2+)-treated groups (27%, p<0.05). Next, after microinjection of spermatozoa incubated with 1.9 mM SrCl2 (n=51), 45% of injected oocytes cleaved on day 2, and 18% developed to blastocysts on day 7 (sham-injection, n=48: 15% to cleavage and 0% to blastocyst). These results demonstrate that Sr2+ is likely to positively affect the fertilizing capacity of spermatozoa in the pig. 相似文献
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Lori K. Davis Bradley K. Fox Chhorn Lim Naoshi Hiramatsu Craig V. Sullivan Tetsuya Hirano E. Gordon Grau 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2009,154(2):249-254
Mozambique tilapia, (Oreochromis mossambicus), are a euryhaline teleost and an important biological model species. Captive male tilapia frequently have high levels of the estrogen-induced yolk precursor protein vitellogenin (Vg), a common indicator of exposure to estrogenic compounds. Sex steroids are found in commercial fish diets, but relatively few studies have examined the relationship between commercial diets and Vg production. In a fasting experiment to ascertain a dietary role in male Vg production, plasma Vg was reduced to negligible levels after 2 weeks of fasting, while no change in estrogen receptor (ER) expression was seen. When male tilapia were fed a squid-based diet that replaced the commercial trout diet, plasma Vg was reduced to undetectable levels over 40 days, concomitant with significant reductions in hepatic expression of Vgs A, B, and C, and ERβ, compared with control fish fed commercial trout diet. Female tilapia fed the squid-based for 20 days had no change in these parameters. When male tilapia were fed a defined, soy-based diet, plasma Vg reduced to 20% of levels in fish given either commercial trout diet or a defined, fishmeal-based diet. Overall, results from these studies suggest that estrogens in a commercial trout diet induce vitellogenin production by increasing expression of Vg, but not ER genes in male tilapia. 相似文献
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Akira Kubota Fang He Manabu Kawase Gaku Harata Masaru Hiramatsu Hisakazu Iino 《Current microbiology》2011,62(1):71-77
This study was conducted to evaluate the potential association between intestinal bifidobacteria and Japanese cedar pollinosis
(JCPsis) and possible influences of probiotic intervention. In this study, fecal samples were the collected from 29 JCPsis
patients. The qualitative and quantitative analyses of fecal bifidobacteria were conducted by quantitative real-time PCR with
16S rRNA-gene-targeted species-specific primers before cedar pollen spread and after a 10-week intervention with fermented
milk prepared with Lactobacillus GG and L. gasseri TMC0356 during pollen spread. Each JCPsis patient had a unique diversity of bifidobacteria, which varied qualitatively and
quantitatively in an individual-dependent manner during pollen spread. The serum IgE concentration of JCPsis patients with
more than 3 detectable Bifidobacterium species was significantly lower than that of patients with less than 2 detected species. The prevalence of B. adolescentis, B. longum, and B. catenulatum increased after probiotic intervention, although the changes were not statistically significant. These results suggest that
lower diversity of intestinal Bifidobacterium species might be a pathological aspect of JCPsis. The diversity of intestinal bifidobacteria could be a prospective target
for using probiotics in the management of IgE-mediated allergic disorders including JCPsis. 相似文献
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Zhang M Ito T Li S Jin J Takeuchi F Lauderdale TL Higashide M Hiramatsu K 《FEMS microbiology letters》2011,323(1):20-28
The genes lukS-PV and lukF-PV for Panton-Valentine leukocidin (PVL) that confers high virulence to Staphylococcus aureus are located on the prophages (PVL phages) which have been classified into group 1 and 2 sfi21-like Siphoviridae. We report novel PVL phages lysogenized in ST59 methicillin-resistant Staphylococcus aureus (MRSA) strains isolated in Japan (JCSC7247) and Taiwan (JCSC5967). The genomes of φ7247PVL and φ5967PVL showed more than 99% identity, and the regions containing the five genes located at both ends of the prophages, int (integrase), hol (holin), ami (amidase), lukS-PV, and lukF-PV, are highly homologous to extant PVL phages. The genes for the structural module are less homologous to these phages, but are highly homologous to non-PVL phages belonging to group 3 Sfi21-like Siphoviridae, for example φN315. Subsequent PCR identification and nucleotide sequencing of an additional 11 Taiwanese ST59 MRSA isolates suggested they all carry the same phage as φ5967PVL, which differed from φ7247PVL by a single base. This study adds evidence to the notion that novel PVL phages would be generated through illegitimate recombination events by acquiring the region at which hol, ami, luk, and int genes would line up upon lytic growth, and suggests that the PVL-positive MRSA clones that have emerged worldwide may carry distinct phages. 相似文献
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Tamoi M Hiramatsu Y Nedachi S Otori K Tanabe N Maruta T Shigeoka S 《Photosynthesis research》2011,108(1):15-23
We generated transgenic tobacco plants with high levels of fructose-1,6-bisphosphatase expressing cyanobacterialfructose-1,6-/sedoheptulose-1,7-bisphosphatase
in the cytosol. At ambient CO2 levels (360 ppm), growth, photosynthetic activity, and fresh weight were unchanged but the sucrose/hexose/starch ratio was
slightly altered in the transgenic plants compared with wild-type plants. At elevated CO2 levels (1200 ppm), lateral shoot, leaf number, and fresh weight were significantly increased in the transgenic plants. Photosynthetic
activity was also increased. Hexose accumulated in the upper leaves in the wild-type plants, while sucrose and starch accumulated
in the lower leaves and lateral shoots in the transgenic plants. These findings suggest that cytosolic fructose-1,6-bisphosphatase
contributes to the efficient conversion of hexose into sucrose, and that the change in carbon partitioning affects photosynthetic
capacity and morphogenesis at elevated CO2 levels. 相似文献
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