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The effects of acetyl-l-carnitine (ALC) supplementation during IVM on subsequently vitrified buffalo oocytes were evaluated, followed by determination of the mitochondrial DNA copy number, measurement of mitochondrial membrane potential (MMP) and identification of the lipid profile of oocyte membranes as markers of oocyte quality after vitrification. Supplementation with ALC during IVM significantly improved the rates of oocyte cleavage and morula and blastocyst formation, and increased MMP after vitrification compared with unsupplemented vitrified oocytes (P < 0.05). Using a bidirectional orthogonal projection to latent structures discriminant analysis based on positive ion matrix-assisted laser desorption ionisation time-of-flight mass spectrometry data, five phospholipid ions (m/z 728.7 (phosphatidylcholine (PC) 32:3), 746.9 (PC 32:5), 760.6 (PC 34:1), 768.8 (PC P-36:3) and 782.6 (PC 36:4); P < 0.05) were identified as significantly more abundant in fresh oocytes than in unsupplemented vitrified oocytes. Meanwhile, three phospholipid ions (m/z 734.6 (PC 32:0), 760.6 (PC 34:1), and 782.6 (PC 36:4); P < 0.05) were more abundant in ALC-supplemented vitrified oocytes than in unsupplemented vitrified oocytes. Therefore, supplementation with ALC during IVM may improve buffalo oocyte quality after vitrification by enhancing mitochondrial function and altering the phospholipid composition of vitrified oocyte membranes. This is the first report that acetyl-l-carnitine (ALC) supplementation during IVM affects phospholipids profiles of buffalo oocytes after vitrification. Supplementation with ALC has beneficial effects on mitochondrial function and alters the phospholipid composition of vitrified oocyte membranes. ALC improves the quality of mature buffalo oocytes and increases the success of embryo development after vitrification. [ABSTRACT FROM AUTHOR]

[Objective]The present experiment was conducted to screen optimum concentration of mitomycin-C to prepare stem cell feeder layer, in order to lay the foundation for establishing and perfecting culture system of embryonic stem cell feed layer. [Method]Using STO (SIM mouse enbryo-derived thioguanine and ouabain resistant) cells, MEF (mouse embryonic fibroblasts) cells and BRL (buffalo rat liver) cells as materials, these cells with the confluence of 90%-100% were treated with mytomycin-C at 0, 2.5, 5.0, 10.0, 15.0 and 20.0 μg/mL for 2 h, respectively, then which were cultured sequentially in medium without mytomycin-C for 3 days. Finally, the survival number and proliferation percentage of each treatment were calculated statistically, and the proliferation of feeder layer cell was detected by using EdU immunofluorescence. [ Result] The results showed that, the ratio of proliferous cells to total cells number decreased gradually with the increase of mitomycin-C concentration. Therefore, the optimum concentrations of mytomycin-C with for STO, BRL and MEF cells were 5.0, 10.0 and 10.0 μg/mL, respectively, the corresponding proliferous cell ratio was 6.8% , 3.0% and 2.1%, respectively. [Conclusion]The mitomycin-C can effectively inhibit feeder layer cell from proliferating and keep its good activity. While there are some differences in optimum concentration of mitomycin-C among cells between different feeder layer. [ABSTRACT FROM AUTHOR]

[Objective]The effect of vitrification and different parthenogenetic activations on the potential development of vitrified-warmed buffalo oocytes was studied to provide references for establishment of a specific activation protocol. [Method]The matured buffalo oocytes were cryopreserved for 1-2 days by vitrification method. Oocytes were treated by parthenogenetic activation after vitrification and thawing, and untreated fresh matured oocytes were used as the control. Following parthenogenetic activation, the effects of ionomycin concentration, concentration and processing time of 6-DMAP on vitrified-warmed oocytes were evaluated. [Result]The cleavage, 4-cell, 8-cell and blastocyst development rates of vitrified-thawed oocytes were all significantly lower than the control group(P<0.01). The vitrified-thawed matured buffalo oocytes were cultured in 6-DMAP at 2 mmol/L for 2 hours after treated with 3.5 μmol/L ionomycin for 5 minutes, and the rates of cleavage, 4-cell, 8-cell and blastocyst were 60.6%, 45.1%, 33.7% and 14.8%, respectively. [Conclusion]The threshold of vitrified-thawed oocytes after activation might have changed, therefore, vitrified matured buffalo oocytes need a specific parthenogenetic activation protocol different from the unverified fresh oocytes. [ABSTRACT FROM AUTHOR]

The article presents a study that evaluates the vitrification of in-vitro produced porcined parthenogentic embryos under different centrifugal liquids.

An abstract of the article "Cloning of Guangxi bama minipig Oct4 gene and its expression in fibroblast cells," by Li Qing-Yang and colleagues is presented.

The article presents a study on the nuclei DNA methylation pattern of in vitro fertilization (IVF), hand-made cloning (HMC), and parthenogenetic activation (PA) during the early period of embryogenesis.

The article presents a study on an interspecies somatic cell nuclear transfer of long-tailed macaque ear fibroblast cells to enucleated oocytes of swine.

The article presents a study which discusses electric fusion and activation effects on cloned Guangxi Bama mini-pig embryos production.

The article presents a study which analyzes the ratio of ribonucleic acid (RNA) in swine spermatozoa and testis. The ratio of RNA were detected and analyzed by RT-PCR and polymerase chain reaction (PCR). The study reveals the two significant difference between the bands of total RNAs from spermatozoa and testis. It also indicates that there are no significant difference between bands of total RNA electrophoresis from spermatozoa and testis.

For addressing the difficulties in the registration of multimodal images in image-matching guidance, a new visualinfrared image-registration approach based on ellipse symmetrical orientation moment was proposed. Scale and affine invariant maximally stable external regions features were extracted to fit the ellipse area in multimodal images. Cluster segmentation was used to automatically select the homogeneous regional features that were invariant between multimodal images. The ellipse symmetrical orientation moment was used to describe the similarity of the regional feature edges in different orientations. Based on the mutual-correlation criterion, the matching feature pairs of the visual and infrared images were obtained. The matching correction strategy was used to reduce the probability of mismatching. The experiments demonstrate that the matching success rate of the corresponding feature pairs between the visual and infrared image is improved to more than 95%, and the computation time is reduced by nearly half as compared with that required by traditional algorithms. The proposed algorithm can meet the image-registration algorithm requirements of a higher success rate and rapid speed as well as strong anti-jamming and stabilization for image-matching guidance.

In order to improve the efficiency of infrared small target detection against complex background, the image was decomposed into three regions flat region, edge region and small target region. A method of nonlinear local filter detection using the Laplaclan pyramid was presented based on each character of the three components. Firstly, Gaussian pyramids were built for the image, each level was subtracted from the original image with matching size, and the flat region was restrained by simple threshold operation. Secondly, the minimum difference between the marked pixel gray value and the mean value of the hollow annular region was used as quota to filter out the edge region. At last, each layer coefficient of the Laplacian pyramid was generated from the results of nonlinear local filtering and then a high-contrast detection image was reconstructed. The isolated noise points were removed based on the character of the neighborhood and the infrared small target was marked by simple threshold operation. Compared with other existing methods, the experimental results show that this method can effectively restrain complex background and the detection speed is fast.

The hot ductility of a Ti-bearing microalloyed steel was studied at temperatures of 600 to 1350 ℃ by a thermal simulator Gleeble 1500.The fracture morphology and microstructure were observed by scanning electron microscopy and optical microscopy.The precipitate behavior of second phase particles was calculated by the thermodynamic software Factsage.The hot ductility curve shows that SS400 B steel with additional titanium has very good hot ductility during all the tested temperature range,and all the values of reduction in area are larger than 45%.AlxTiyOz generation at high temperature can act as nucleation sites for dimples to promote the ductile fracture.The amount of detrimental Al N can be reduced due to the formation of AlxTiyOz and Ti N.Intergranular ferrite and cementite promote the intergranular brittle fracture.

Nanos2 belongs to the Nanos gene-coding family and is an important RNA-binding protein that has been shown to have essential roles in male germline stem cells development and self-renewal in mouse. However, little is known about Nanos2 in inchoate buffalo spermatogonia. Here, rapid-amplification of cDNA ends (RACE) was used to obtain the full-length buffalo Nanos2 sequence and bioinformatic analysis revealed a highly conserved Nanos2 sequence between buffalo and other mammalian species. Although Nanos2 was expressed in various tissues, the highest mRNA expression levels were found in testes tissue. Moreover, Nanos2 mRNA was abundant in fetal and pre-puberal testes but markedly decreased in the testes of adults. At the protein level, immunohistochemistry in pre-puberal testes revealed a pattern of NANOS2 expression similar to that for the undifferentiated type A spermatogonia marker PGP9.5. Furthermore, NANOS2 expression was low in adult testes and restricted to elongating spermatids. Altogether, our data suggest that Nanos2 is a potential preliminary molecular marker of inchoate buffalo spermatogonia, and may play an important role in buffalo spermatogonial stem cells (SSCs) development and self-renewal, as has been observed in other model animals. [ABSTRACT FROM AUTHOR]

The pig is an ideal source to provide organs because its organ size and physiology are similar to humans. However, an acute rejection will ensue after pig-to-human xenotransplantation. The α-1,3 galactosyltransferase gene knockout (GTKO) pigs were generated in recent years, and could solve the problem of hyperacute rejection. But due to lack of reporting genes, the rejection status of cells and organs post pig-to-human xenotransplantation cannot be visualized. In this study, we introduced the enhanced green fluorescent protein (EGFP) gene driven by the CAG promoter into GTKO porcine ear fibroblasts. Then we produced transgenic pigs expressing the EGFP gene by nuclear transfer technology. Expression levels of EGFP in different tissues and organs of the cloned pig were investigated by Nightsea DFP-1 Fluorescent Protein Flashlight, fluorescence microscope and quantitative PCR assays. The results showed that the protein and transcript of EGFP were expressed in all tissues and organs of the GTKO pig, but the expression was weak in the liver and central nervous system. In conclusion, we have successfully produced the transgenic GTKO pigs expressing EGFP in all tested tissues and organs, which builds up a good basis to track transplanted cells or tissues.