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Jia B.,China Agricultural University | Wu G.,Yunnan Animal Science and Veterinary Institute | Fu X.,China Agricultural University | Mo X.,China Agricultural University | And 3 more authors.
Molecular Reproduction and Development | Year: 2014

The aim of this study was to determine the effects of trans-10, cis-12 conjugated linoleic acid (t10c12 CLA) supplementation on oocyte maturation and embryo development in pigs. Compared with the control, supplementation of 50μM t10c12 CLA to in vitro maturation (IVM) medium significantly increased the proportion of oocytes at the metaphase-II (MII) stage and subsequent parthenogenetic embryo development in terms of cleavage rate, blastocyst formation rate, and cell numbers in blastocysts. The t10c12 CLA-treated oocytes resumed meiotic maturation and progressed to the MII stage significantly faster than those of control. The expression of phosphorylated mitogen-activated protein kinase 3/1 (p-MAPK3/1) and cyclooxygenase-2 (COX2) in cumulus oocyte complexes (COCs) at 5, 10, and 22hr of IVM were significantly increased in the t10c12 CLA-treatment group. The level of p-MAPK3/1 in t10c12 CLA-treated MII oocytes was also higher (P<0.05) than that of control. Moreover, t10c12 CLA supplementation partially overcame the negative effects of U0126 on cumulus expansion and nuclear maturation, and completely recovered COX2 protein levels in the presence of U0126. Treatment of COCs with NS398 also significantly suppressed cumulus expansion and nuclear maturation, which was overcome by t10c12 CLA. Yet, this simulatory effect of t10c12 CLA was blocked in the presence of both U0126 and NS398. The t10c12 CLA treatment significantly reduced reactive oxygen species level and increased glutathione concentrations in MII oocyte. In conclusion, supplementation of t10c12 CLA during porcine oocyte maturation exerts its beneficial effects on nuclear and cytoplasmic maturation, which contributes to enhancing subsequent embryo development. © 2013 Wiley Periodicals, Inc.

Mo X.,China Agricultural University | Wu G.,Yunnan Animal Science and Veterinary Institute | Yuan D.,China Agricultural University | Jia B.,China Agricultural University | And 3 more authors.
Molecular Reproduction and Development | Year: 2014

SUMMARY: The present study was conducted to examine the effects of leukemia inhibitory factor (LIF) on bovine oocyte maturation and early embryo development in vitro. Results showed that LIF supplementation (25ng/ml) enhanced nuclear maturation of intact cumulus-oocyte complexes (COCs) compared to the vehicle control. Similar results were observed in denuded oocytes, indicating that LIF directly influences oocyte development. LIF-treated oocytes showed a higher cortical-granule-migration rate and increased expression of CD9, a tetraspanin transmembrane protein essential for fertilization. After in vitro fertilization, oocytes receiving LIF supplementation exhibited a higher cleavage rate and yielded a significantly higher number of blastocysts. To further dissect the molecular mechanism underlying this LIF-induced bovine oocyte maturation phenotype, we examined the involvement of two signaling cascades, mitogen-activated protein kinases (MAPK3/1)- and the signal transducer and activator of transcription 3 (STAT3)-dependent pathways. Western blot results revealed that LIF phosphorylated MAPK3/1 and STAT3. Inhibition of MAPK3/1 activation with MEK inhibitor U0126 only partially blocked LIF-induced nuclear maturation, although it attenuated oocyte cytoplasmic maturation. Inhibition of JAK/STAT3 activation with a specific pharmacological inhibitor completely abolished the LIF-response in bovine oocyte. In summary, these data revealed a novel role for LIF in bovine oocyte maturation subsequent embryonic development. Mol. Reprod. Dev. 81: 608-618, 2014. © 2014 Wiley Periodicals, Inc.

Cai C.,University of Western Australia | Li H.,Yunnan Animal Science and Veterinary Institute | Edwards J.,University of Western Australia | Hawkins C.,Western Australian Department of Agriculture and Food | Robertson I.D.,University of Western Australia
Preventive Veterinary Medicine | Year: 2014

Foot and mouth disease (FMD) outbreaks have been reported in China for many years. Recently, due to the rapid economic development, the price of meat and its demand have grown quickly. This trend has resulted in an increase in the number of livestock moving from south-east Asian countries into China. Foot and mouth disease is becoming one of the most important trans-boundary animal diseases affecting the livelihood of livestock owners in China. To contribute to the long term goal to control and eradicate FMD from China, the Chinese government has adopted a series of control measures which includes compulsory routine vaccination against the disease. In this paper, the surveillance results of the routine vaccination programme were systemically reviewed. The results from 28 published papers were combined and analysed through a meta-analysis approach. The results of the meta-analysis indicated that the vaccination programme has been very successful in China with more than 70% of animals protected against serotypes Asia-1 and O. © 2014 Elsevier B.V.

Chen W.,Kunming University of Science and Technology | Yang H.,Yunnan Animal Science and Veterinary Institute | Tang W.-R.,Kunming University of Science and Technology | Feng S.-J.,Kunming University of Science and Technology | Wei Y.-L.,Kunming University of Science and Technology
Asian Pacific Journal of Cancer Prevention | Year: 2014

Background: Several studies have been performed to investigate the association of the HER2 Ile655Val polymorphism and breast cancer risk. However, the results were inconsistent. To understand the precise relationship, a meta-analysis was here conducted. Materials and Methods: A search of PubMed conducted to investigate links between the HER2 Ile655Val polymorphism and breast cancer, identified a total of 32 studies, of which 29, including 14,926 cases and 15,768 controls, with odds ratios (ORs) with 95% confidence intervals were used to assess any association. Results: In the overall analysis, the HER2 Ile655Val polymorphism was associated with breast cancer in an additive genetic model (OR = 1.136, 95% CI 1.043-1.239, p = 0.004) and in a dominant genetic (OR = 1.118, 95% CI 1.020-1.227, p = 0.018), while no association was found in a recessive genetic model. On subgroup analysis, an association with breast cancer was noted in the additive genetic model (OR = 1.111, 95% CI: 1.004-1.230, p = 0.042) for the Caucasian subgroup. No significant associations were observed in Asians and Africans in any of the genetic models. Conclusions: In summary, our meta-analysis findings suggest that the HER2 Ile655Val polymorphism is marginally associated with breast cancer susceptibility in worldwide populations with additive and dominant models, but not a recessive model.

Quan G.B.,Yunnan Animal Science and Veterinary Institute | Hong Q.H.,Yunnan Animal Science and Veterinary Institute | Shao Q.Y.,Yunnan Animal Science and Veterinary Institute | Yang H.Y.,Yunnan Animal Science and Veterinary Institute | Wu S.S.,Yunnan Animal Science and Veterinary Institute
Cryo-Letters | Year: 2012

To improve the quality of frozen spermatozoa of Yunnan semi-fine wool sheep, the protective effect of trehalose and sucrose on frozen ram spermatozoa during a non-mating season was evaluated and compared in this study. Briefly, following collection by electric stimulation equilibration at 5°C following dilution with the freezing extender and pre-freezing in liquid nitrogen vapor, the ram spermatozoa were frozen in liquid nitrogen. After thawing, viability, motility, acrosome status, membrane integrity, and phosphatidylserine (PS) distribution was determined using a computer-assisted spermatozoa analysis system and flow cytometry. The data indicated disaccharide can improve the quality of frozen ram spermatozoa. With a trehalose concentration of 100mM, the post-thaw viability and motility (80.56%±6.89% and 46.07%±5.84%) of ram spermatozoa were significantly more than those of ram spermatozoa frozen with no disaccharide (65.46%±18.96% and 34.62%±9.32%, P<0.05). However, the effect of sucrose on the viability, motility, and moving velocity of ram spermatozoa was similar to that of the control group (P<0.05). Compared with sucrose, trehalose can significantly increase the motility of frozen ram spermatozoa (P<0.05). In addition, addition of trehalose or sucrose can efficiently protect the acrosome of frozen spermatozoa. Moreover, when the concentration of trehalose or sucrose was 100mM, the protective effect of trehalose or sucrose on the membrane integrity and PS distribution was significantly higher than that of the control group (P0.<05). However, the protective effect of trehalose on viability, moving velocity, acrosome status, membrane integrity, and PS distribution of frozen ram spermatozoa was similar to that of sucrose (P<0.05). In conclusion, the protective effect of trehalose on frozen sheep spermatozoa is superior to that of sucrose. Addition of 100mM of trehalose in the freezing extenders can improve the post-thaw quality of ram spermatozoa with respect to viability, motility, and linear velocity. Moreover, presence of disaccharide can protect acrosome and membrane of frozen sheep spermatozoa. © CryoLetters.

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