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The Tibetan sheep is an indigenous breed living in the entire Tibetan Plateau, and its origin and phylogenic relationships are still uncertain and controversial. In this study, we analyzed partial mtDNA D-loop sequences of 156 Chinese Tibetan sheep individuals from 12 distributed geographic ecotype populations. Phylogenetic analysis indicated that three maternal lineages (haplogroups A, B and C) were found in this breed and that Ovis vignei and Ovis ammon have possibly contributed to the original Tibetan sheep. The absence of haplogroups D and E in Tibetan sheep suggests that this breed did not originate in the Middle East, China. [ABSTRACT FROM AUTHOR]

Fecundity is an important trait for the reproduction of economically domestic animals. Some microsatellites related to the fecundity of domestic animals have been identified. In the current study, we investigated five fecundity related microsatellites, including BM1329, BM143, LSCV043, OarHH35, and OarHH55, which had been identified in sheep. We estimated their diversity and population structure in three high fecundity goats (Jianzhou big ear goat, Jining grey goat, Dazu black goat) and three low fecundity goats (Boer goat, Nubian goat, Inner Mongolia Cashmere goat). The results revealed a high diversity of those markers in the goat populations. The population structure did not diverge significantly between high fecundity goats and low fecundity populations, but it followed the agro-ecological zone and management history. This indicated that the frequency of those five microsatellites did not increase during the reproduction of those six breeds. Therefore, these five fecundity related microsatellites are not appropriate biomarkers for goat breeding. [ABSTRACT FROM AUTHOR]

Despite much attention, history of sheep (Ovis aries) evolution, including its dating, demographic trajectory and geographic spread, remains controversial. To address these questions, we generated 45 complete and 875 partial mitogenomic sequences, and performed a meta-analysis of these and published ovine mitochondrial DNA sequences (n = 3,229) across Eurasia. We inferred that O. orientalis and O. musimon share the most recent female ancestor with O. aries at approximately 0.790 Ma (95% CI: 0.637-0.934 Ma) during the Middle Pleistocene, substantially predating the domestication event (~8-11 ka). By reconstructing historical variations in effective population size, we found evidence of a rapid population increase approximately 20-60 ka, immediately before the Last Glacial Maximum. Analyses of lineage expansions showed two sheep migratory waves at approximately 4.5-6.8 ka (lineages A and B: ~6.4-6.8 ka; C: ~4.5 ka) across eastern Eurasia, which could have been influenced by prehistoric West-East commercial trade and deliberate mating of domestic and wild sheep, respectively. A continent- scale examination of lineage diversity and approximate Bayesian computation analyses indicated that the Mongolian Plateau region was a secondary center of dispersal, acting as a "transportation hub" in eastern Eurasia: Sheep from the Middle Eastern domestication center were inferred to have migrated through the Caucasus and Central Asia, and arrived in North and Southwest China (lineages A, B, and C) and the Indian subcontinent (lineages B and C) through this region. Our results provide new insights into sheep domestication, particularly with respect to origins and migrations to and from eastern Eurasia. [ABSTRACT FROM AUTHOR]

Epithelial growth factor (EGF) and basic fibroblast growth factor (bFGF), and their receptors, epithelial growth factor receptor (EGFR) and bFGF receptor (bFGFR), are frequently overexpressed in high-grade gliomas. In the present study, the EGF and bFGF levels in U251 glioblastoma cell culture supernatants were determined by ELISA, and enhanced green fluorescent protein (EGFP)-labeled recombinant lenti-viral expression vectors with small interfering RNA targeting the EGFR and bFGFR genes were constructed. The mRNA expression levels of EGFR, bFGFR, cluster of differentiation (CD)133, glial fibrillary acidic protein (GFAP), tubulin-β3 (TUBB3) and myelin basic protein (MBP) were determined using quantitative polymerase chain reactions in U251 cells prior to and following silencing of the EGFR and/or bFGFR genes. Prior to silencing, the U251 cells secreted EGF and bFGF, and expressed EGFR, bFGFR, CD133, GFAP, TUBB3 and MBP mRNA. Subsequent to silencing the EGFR and/or bFGFR gene, CD133 mRNA expression decreased and GFAP and TUBB3 mRNA expression increased. Silencing the EGFR and FGFR genes acted synergistically to downregulate CD133 expression. The downregulation of CD133 mRNA expression and the upregulation of GFAP and TUBB3 mRNA expression were not significantly different when blocking the EGFR and FGFR pathways. These results indicate that autocrine or paracrine EGF and/or FGF mechanisms exist in U251 cells. Knocking down the EGFR and/or FGFR genes downregulates CD133 mRNA expression and facilitates glial and neuronal differentiation in U251 cells. [ABSTRACT FROM AUTHOR]

Mammalian oocyte maturation and early embryo development processes are Ca2+-dependent. In this study, we used confocal microscopy to investigate the distribution pattern of Ca2+ and its dynamic changes in the processes of bovine oocytes maturation, in vitro fertilization (IVF), parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT) embryo development. During the germinal vesicle (GV) and GV breakdown stage, Ca2+ was distributed in the cortical ooplasm and throughout the oocytes from the MI to Mil stage. In IVF embryos, Ca2+ was distributed in the cortical ooplasm before the formation of the pronucleus. In 4-8 cell embryos and morulas, Ca2+ was present throughout the blastomere. In PA embryos, Ca2+ was distributed throughout the blastomere at 48 h, similar to in the 4-cell and 8-cell phase and the morula. At 6 h after activation, there was almost no distribution of Ca2+ in the SCNT embryos. However, Ca2+ was distributed in the donor nucleus at 10 h and it was distributed throughout the blastomere in the 2-8 cell embryos. In this study, Ca2+ showed significant fluctuations with regularity of IVF and SCNT groups, but PA did not. Systematic investigation of the Ca2+ location and distribution changes during oocyte maturation and early embryo development processes should facilitate a better understanding of the mechanisms involved in oocyte maturation, reconstructed embryo activation and development, ultimately improving the reconstructed embryo development rate. [ABSTRACT FROM AUTHOR]

A Ujumqin sheep ear marginal tissue (USEM) fibroblast line, frozen in 147 cryovials with 4 × 106 cell each, was successfully established from 33 Ujumqin sheep ear marginal tissues using explant culture and cryopreservation techniques. The cells were morphologically consistent with fibroblasts. The growth curve was typical S-shape and the cell population passed through a lag phase, a logarithmic phase and a plateau phase. The population doubling time (PDT) was approximately 72 h. Tests for bacteria, fungi, viruses and mycoplasma were all negative. Isoenzyme polymorphism indicated that the genetic characteristics of the cell line were stable in vitro. Karyotyping analysis indicated that the chromosome number of a normal cell was of 2 n = 54 and 95.4% of the entire population was diploid. The transfection efficiencies of six fluorescent proteins (pEGFP-N3, pEGFP-C1, pDsRed-N1, pEYFP-N1, pECFP-N1 and pECFP-mito) optimal at 48 h were from 18.5% to 30.1%. The cell line met all criteria from the American Type Culture Collection (ATCC). Not only has the germline of this important sheep breed been preserved at the cell level, but also valuable material had been provided for genome, postgenome and somatic cloning research. Moreover, the establishment of this technical platform may provide both technical and theoretical support for storing the genetic resources of other animals and poultry at the cell level. [ABSTRACT FROM AUTHOR]

As the fast pace of genomic research continues to identify mitochondrial lineages in animals, it has become apparent that many independent studies are needed to support a robust phylogenetic inference. The aim of this study was thus to further characterize the maternal lineage, proposed to originate in southwestern region of China, using a wider survey of diverse goat breeds in China. To this end, we sequenced the mitochondrial hypervariable region 1 (HVR1) of the mtDNA control region in 145 goats of 12 Chinese breeds. Phylogenetic analysis revealed that Chinese goats were classified into four distinct lineages (A, B, C and D) as previously reported. A Mantel test and the analysis of Analysis of Molecular Variance (ANOVA) indicated that there was not an obvious geographic structure among Chinese goat breeds. Population expansion analysis based on mismatch distribution and Fu's Fs statistic indicate that two expansion events in Chinese goats occurred respectively at about 11 and 29 mutational time units ago, revealing two star-like subclades in lineage B corresponding to two population expansion events. Moreover, lineage B sequences were presented only in the breeds of southwestern or surrounding regions of China. Multiple lines of evidence from this study and previous studies indicate that for Chinese goats mtDNA lineage B originated from the southwestern region of China. [ABSTRACT FROM AUTHOR]

Abstract   Background Choroid plexus papillomas are rare tumors of the central nervous system and are usually confined to the ventricle system. We describe a choroid plexus papilloma located in the sella turcica that was identified pathologically. Case description A 49-year-old woman with a 5-year history of progressive visual deterioration in the left eye was admitted to our hospital. Neurological examination found no abnormality except for the perception of light and secondary optic atrophy in her left eye. Careful endocrine testing did not show any hormone excess or deficiency of the pituitary and target glands. Magnetic resonance imaging demonstrated a hemorrhagic mass in the sellar region, which occupied the entire sella turcica and extended to the suprasellar cistern. The mass was excised via an endonasal trans-sphenoidal approach. Histologic examination proved that the lesion was a choroid plexus papilloma. Conclusion Choroid plexus papillomas arising in and occupying the sella are rare, although some radiographic patterns of ectopic choroid plexus papillomas have been reported. A review of the current literature revealed no similar cases of a choroid plexus papilloma. We discuss the different radiological appearances of choroid plexus papillomas, the differential diagnosis, and treatment. [ABSTRACT FROM AUTHOR]

With the establishment of modern sheep production systems in China, various forms of hybridization with Western breeds and between native breeds have been utilized for genetic improvement. At the same time, the progressive destruction or deterioration of sheep habitat has accompanied urbanization in China. Together these factors have accelerated the loss of genetic diversity, or even resulted in the extinction of some indigenous breeds. It is therefore important that efficient strategies for surveillance, evaluation, conservation and utilization of available genetic resources are developed for this species. In this study, a total of 30 microsatellite markers were used to assess genetic diversity for 12 native breeds and one Western sheep breed in Northern China. The high polymorphism information contents at the 30 markers, varying from averages of 0.519 to 0.666 for the 13 breeds, imply the retention of natural variation from source populations in the domestic breeds from different geographic regions in China. Analysis of genetic differentiation revealed substantial divergence among these breeds. Neutrality tests indicated that more than one third of the 30 loci were in departure from neutrality, implying that some evolutionary forces (e.g. selection and migration) had acted on these populations. Phylogenetic and phylogeographic analyses displayed a remarkable degree of consistency between geographic origins, breeding histories and the pattern of genetic differentiation. [ABSTRACT FROM AUTHOR]