miRNA and piRNA expression profiles of breeder cock testes detected by next‐generation sequencing

miRNAs are small non‐coding regulatory RNAs that play key roles in diverse biological processes. In this study, we used the Solexa sequencing technique to profile miRNAs in breeder cock testes to illustrate their functions. A total of 663 co‐expressed miRNAs and 3,180 co‐expressed piRNAs were detected in three libraries. Based on Mir‐X^? miRNA qRT‐PCR, three miRNAs representing low, medium and high expression levels according to the sequencing results were selected randomly to validate the miRNAs' expression profiles. Results suggested that the miRNA expression profiles data could represent actual miRNA expression levels. Moreover, target genes prediction of the co‐expressed miRNAs and further Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed, which revealed that some candidate miRNAs were involved in the regulation of the spermatogenesis process, spermatozoa function and testicular metabolism. In conclusion, we provided a useful resource for further elucidation of the miRNAs' regulatory role in spermatogenesis, contributing to a preliminary database for functional and molecular mechanistic studies in testicular metabolism, spermatogenesis and other testes functions.     

Fullerene pipes

Single-wall fullerene nanotubes were converted from nearly endless, highly tangled ropes into short, open-ended pipes that behave as individual macromolecules. Raw nanotube material was purified in large batches, and the ropes were cut into 100- to 300-nanometer lengths. The resulting pieces formed a stable colloidal suspension in water with the help of surfactants. These suspensions permit a variety of manipulations, such as sorting by length, derivatization, and tethering to gold surfaces.     

Circular polarization in star- formation regions: implications for biomolecular homochirality

Strong infrared circular polarization resulting from dust scattering in reflection nebulae in the Orion OMC-1 star-formation region has been observed. Circular polarization at shorter wavelengths might have been important in inducing chiral asymmetry in interstellar organic molecules that could be subsequently delivered to the early Earth by comets, interplanetary dust particles, or meteors. This could account for the excess of L-amino acids found in the Murchison meteorite and could explain the origin of the homochirality of biological molecules.     

Comparison of blood glucose concentrations measured by enzymatic and reflectance photometric methods in fasting piglets

Summary

During a metabolic study of 22 fasting newborn piglets, blood glucose concentrations were measured by enzymatic and reflectance photometric methods. Use of the reflectance photometer is an accurate method of determining blood glucose levels even in hypoglycaemic range. In addition, the minimal quantity of blood needed for measurement allows the use of the same newborn piglets in longitudinal studies in which samples must be taken frequently.     

Effect of Transgene Introduction and Recloning on Efficiency of Porcine Transgenic Cloned Embryo Production In Vitro

Retrovirus-mediated exogenous gene transfection of somatic cells is an efficient method to produce transgenic embryos by somatic cell nuclear transfer (SCNT). This study evaluated whether efficiency of transgenic embryos production, by SCNT using fibroblast cells transfected by retrovirus vector, is influenced by the introduced transgene and whether recloning could further improve its efficiency. Transgenic cloned embryos were produced by SCNT of porcine foetal fibroblast cells transfected by either LNβ-Z or LNβ-enhanced green fluorescent protein (EGFP) retrovirus vector and evaluated for their developmental ability in vitro . Blastomeres from four-cell stage porcine embryos, produced by SCNT of foetal fibroblast cells transfected with LNβ-EGFP retroviral vector, were subsequently recloned into enucleated metaphase II oocytes and evaluated for changes in chromatin configuration, in vitro embryo development and gene expression. Analysis of results showed that cleavage and blastocyst rates of porcine SCNT embryos, using LacZ (53.6 ± 6.4%; 12.0 ± 5.7%) or EGFP (57.5 ± 6.3%; 10.1 ± 4.1%) transfected fibroblasts, did not differ (p > 0.05) from those of non-transfected controls (60.9 ± 8.2%; 12.3 ± 4.0%). Recloning of blastomeres did not further improve the in vitro development rate. Interestingly, the nuclei of blastomere underwent slower remodelling process than somatic cell nuclei. Both cloned and recloned embryos showed 100% transgene expression and there were no evidence of mosaicism. In conclusion, our data shows that the efficiency of transgenic cloned embryos production by SCNT of somatic cells transfected with replication-defective retrovirus vector is not influenced by the transgene introduction into donor cells and recloning of four-cell stage blastomere could not further improve its efficiency.     

The role of endotoxin in the pathogenesis of coliform mastitis in sows

Sows were made tolerant to Escherichia coli endotoxin by daily intravenous (IV) injection of the pyrogen. A refractory state was induced, characterised by a markedly decreased fever. In contrast, intramammary (IMM) infusion of only a quarter of the endotoxin dose to which the animals were made tolerant by IV injection produced a markedly increased fever. This finding suggests that inflammatory endogenous mediators were released in the mammary glands and that their subsequent absorption into the blood circulation, and not the absorption of endotoxin caused fever.     

Pathophysiological effects of endotoxins in ruminants. 2. Metabolic aspects

Metabolic disturbances following intravenous and intramammary administration of endotoxins in ruminants are described. In contrast to the similarity in response of blood biochemical parameters after intravenous and intramammary administrations of endotoxins, responses in plasma concentrations of enzyme activities, the thyroid hormones, cortisol, and somatotropin differ markedly. Biochemical changes in blood after endotoxin administration are predominantly dose-dependent; thus some of the biochemical parameters - especially plasma concentrations of Fe and Zn - serve also to evaluate the effects of certain drugs in endotoxin models. Changes in milk composition have been documented only after intramammary infusion of endotoxins and can partly be explained by the increased permeability of the blood/milk barrier. Appearance and production of milk returns to normal within a week after intramammary endotoxin treatment, indicating that the mammary gland is only temporarily damaged by endotoxin-induced mastitis.