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991.
ABSTRACT

1. This experiment investigated the influence of chicken PRDX3 on cell proliferation in chick embryo fibroblast cells using PRDX3 knockdown technology.

2. A methyl thiazolyl tetrazolium (MTT) assay was performed to assess the effect of chPRDX3 knockdown on fibroblast proliferation. The antioxidant effect was investigated to determine if it directly mediated fibroblast cell proliferation.

3. To determine the role of chPRDX3 on cell proliferation, an siRNA mediated knockdown was performed in chick fibroblast cells using an in vitro assay. The proliferation of fibroblast cells transfected with siPRDX3 #3 and siPRDX3 Mix was significantly decreased after 48 h (P < 0.01). In addition, the knockdown of chicken PRDX3 suppressed cell proliferation through an increase in oxidative stress.

4. The results demonstrated that chPRDX3 is required for cell proliferation in chicken fibroblast cells. Such findings have important implications for the maintenance of chicken fibroblast cells.  相似文献   
992.
993.
Inclusion of phytase in animal feedstuff is a common practice to enhance nutrients availability. However, little is known about the effects of phytase supplementation on the microbial ecology of the gastrointestinal tract. In this study, freeze-dried Mitsuokella jalaludinii phytase (MJ) was evaluated in a feeding trial with broilers fed a low available phosphorus (aP) diet. A total of 180 male broiler chicks (day-old Cobb) were assigned into three dietary treatments: Control fed with 0.4% (w/w) of available phosphorus (aP); Group T1 fed low aP [0.2% (w/w)] supplemented with MJ; and T2 fed low aP and deactivated MJ. The source of readily available P, dicalcium phosphate (DCP), was removed from low aP diet, whereby additional limestone was provided to replace the amount of Ca normally found in DCP. For each treatment, 4 replicate pens were used, where each pen consisted of 15 animals. The animals' energy intake and caecal bacterial community were monitored weekly for up to 3 weeks. The apparent metabolizable energy (AME) and apparent digestibility of dry matter (ADDM) of broilers fed with different diets were determined. In addition, the caecal microbial diversities of broilers were assessed using high-throughput next-generation sequencing targeting the V3-V4 region of bacterial 16S rRNA. The results showed that broilers fed with T1 diet have better feed conversion ratio (FCR) when compared to the Control (p < .05) and T2 diets (p < .05), demonstrating the efficiency of MJ as a supplement to low aP diet. Nevertheless, MJ did not significantly affect the microbial population and diversity in broilers' caeca, which mainly consists of members from Bacteroidetes, Firmicutes, and Proteobacteria. Regardless, significant variations in the caecal bacterial composition were observed over time, probably due to succession as the broilers aged. This is the first reported study on the effect of MJ on the microbial diversity of broiler's caeca.  相似文献   
994.
995.
This study investigated the relationship between acrosome reactions and fatty acid composition with respect to fertility in boar sperm. The acrosome reaction was induced more than 85% by 60 mM methyl-beta-cyclodextrin (MBCD), and plasma membrane integrity was significantly reduced dependent on the MBCD level in boar sperm (p < .05). The acrosome-reacted sperm exhibited significantly higher saturated fatty acids (SFAs) and lower polyunsaturated fatty acids (PUFAs) composition compared to the non-acrosome reaction group (< .0001). In addition, the PUFAs, C22:5n-6 (docosapentaenoic acid [DPA]; p < .01) and C22:6n-3 (docosahexaenoic acid [DHA]; < .0001) were significantly decreased, and cleavage and blastocyst formation of oocytes were significantly (< .0001) decreased in acrosome-reacted sperm relative to non-acrosome-reacted sperm. Moreover, acrosome reaction was positively correlated with SFAs, whereas negatively correlated with PUFAs, of the PUFAs, the DPA (p = .0005) and DHA (= <.0001) were negatively correlated with the acrosome reaction. Therefore, these results suggest that the PUFAs composition of sperm is closely involved in acrosome reaction in pigs.  相似文献   
996.
Quantitative analysis of the normal retrograde urethrogram is well reported in radiography, but studies on CT urethrography are lacking. Recently, a method of retrograde CT urethrography using a power injector was described. The purpose of the current, prospective, analytical study was to quantify the urethral size of five, healthy, intact, male Beagle dogs using retrograde CT urethrography and a power injector. With the injection rate of the power injector set at 0.3 mL/s, 1 mL/kg of diluted contrast medium (15 mg I/mL) was injected, and a CT examination was performed. The state of the initial urethrogram taken was defined as “empty bladder.” The same procedures were repeated with the injection of an additional 1 mL/kg of diluted contrast medium until the ureteral reflux was seen (distended bladder). There was a significant difference in volumes between the empty and distended bladder, but the membranous urethra showed the least difference (= .0044) among the three regions (< .0001 for the prostatic and penile urethra). Urethral diameters at six sites were measured from sagittal images, and the sites of measurements were adopted from the earlier radiographic studies. The most significant difference in the urethral diameters between the empty and distended bladder occurred at the cranial and middle prostatic urethra (< .0001). The results of this study can be useful for interpreting the results of retrograde CT urethrography. Care must be taken when narrowing is suspected at the prostatic urethra, and if necessary, further distension of the urinary bladder should be tried.  相似文献   
997.
We demonstrated entanglement distribution between two remote quantum nodes located 3 meters apart. This distribution involves the asynchronous preparation of two pairs of atomic memories and the coherent mapping of stored atomic states into light fields in an effective state of near-maximum polarization entanglement. Entanglement is verified by way of the measured violation of a Bell inequality, and it can be used for communication protocols such as quantum cryptography. The demonstrated quantum nodes and channels can be used as segments of a quantum repeater, providing an essential tool for robust long-distance quantum communication.  相似文献   
998.
Journal of Soils and Sediments - This study was conducted to investigate variations in the stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) of agricultural soils under different...  相似文献   
999.
1000.
Transgenic research on cattle embryos has been developed to date using viral or plasmid DNA delivery systems. In this study, a different gene delivery system, piggybac transposition, was employed to investigate if it can be applied for producing transgenic cattle embryos. Green or red fluorescent proteins (GFP or RFP) were transfected into donor fibroblasts, and then transfected donor cells were reprogrammed in enucleated oocytes through SCNT and developed into pre-implantation stage embryos. GFP was expressed in donor cells and in cloned embryos without any mosaicism. Induction of RFP expression was regulated by doxycycline treatment in donor fibroblasts and pre-implantational stage embryos. In conclusion, this study demonstrated that piggybac transposition could be a mean to deliver genes into bovine somatic cells or embryos for transgenic research.  相似文献   
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