Selection of reference genes for gene expression studies in pig tissues using SYBR green qPCR

<p>Abstract</p> <p>Background</p> <p>Real-time quantitative PCR (qPCR) is a method for rapid and reliable quantification of mRNA transcription. Internal standards such as reference genes are used to normalise mRNA levels between different samples for an exact comparison of mRNA transcription level. Selection of high quality reference genes is of crucial importance for the interpretation of data generated by real-time qPCR.</p> <p>Results</p> <p>In this study nine commonly used reference genes were investigated in 17 different pig tissues using real-time qPCR with SYBR green. The genes included beta-actin (<it>ACTB</it>), beta-2-microglobulin (<it>B2M</it>), glyceraldehyde-3-phosphate dehydrogenase (<it>GAPDH</it>), hydroxymethylbilane synthase (<it>HMBS</it>), hypoxanthine phosphoribosyltransferase 1 (<it>HPRT1</it>), ribosomal protein L4 (<it>RPL4</it>), succinate dehydrogenase complex subunit A (<it>SDHA</it>), TATA box binding protein (<it>TPB</it>)and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta polypeptide (<it>YWHAZ</it>). The stability of these reference genes in different pig tissues was investigated using the geNorm application. The range of expression stability in the genes analysed was (from the most stable to the least stable): <it>ACTB</it>/<it>RPL4</it>, <it>TBP</it>, <it>HPRT</it>, <it>HMBS</it>, <it>YWHAZ</it>, <it>SDHA</it>, <it>B2M </it>and <it>GAPDH</it>.</p> <p>Conclusion</p> <p>Expression stability varies greatly between genes. <it>ACTB, RPL4</it>, <it>TPB </it>and <it>HPRT1 </it>were found to have the highest stability across tissues. Based on both expression stability and expression level, our data suggest that <it>ACTB </it>and <it>RPL4 </it>are good reference genes for high abundant transcripts while <it>TPB </it>and <it>HPRT1 </it>are good reference genes for low abundant transcripts in expression studies across different pig tissues.</p

Transcriptional immune response in mesenteric lymph nodes in pigs with different levels of resistance to Ascaris suum

AbstractA single nucleotide polymorphism on chromosome 4 (SNP TXNIP) has been reported to be associated with roundworm</jats:p

Dysprosium-carboxylate nanomeshes with tunable cavity size and assembly motif through ionic interactions

We report the design of dysprosium directed metallo-supramolecular architectures on a pristine Cu(111) surface. By an appropriate selection of the ditopic molecular linkers equipped with terminal carboxylic groups (TPA, PDA and TDA species), we create reticular and mononuclear metal–organic nanomeshes of tunable internodal distance, which are stabilized by eight-fold Dy⋯O interactions. A thermal annealing treatment for the reticular Dy:TDA architecture gives rise to an unprecedented quasi-hexagonal nanostructure based on dinuclear Dy clusters, exhibiting a unique six-fold Dy⋯O bonding motif. All metallo-supramolecular architectures are stable at room temperature. Our results open new avenues for the engineering of supramolecular architectures on surfaces incorporating f-block elements forming thermally robust nanoarchitectures through ionic bonds

Charge Transfer-Mediated Dramatic Enhancement of Raman Scattering upon Molecular Point Contact Formation

Charge-transfer enhancement of Raman scattering plays a crucial role in current-carrying molecular junctions. However, the microscopic mechanism of light scattering in such nonequilibrium systems is still imperfectly understood. Here, using low-temperature tip-enhanced Raman spectroscopy (TERS), we investigate how Raman scattering evolves as a function of the gap distance in the single C60-molecule junction consisting of an Ag tip and various metal surfaces. Precise gap-distance control allows the examination of two distinct transport regimes, namely tunneling regime and molecular point contact (MPC). Simultaneous measurement of TERS and the electric current in scanning tunneling microscopy shows that the MPC formation results in dramatic Raman enhancement that enables one to observe the vibrations undetectable in the tunneling regime. This enhancement is found to commonly occur not only for coinage but also transition metal substrates. We suggest that the characteristic enhancement upon the MPC formation is rationalized by charge-transfer excitation

A 2D rhomboidal system of manganese(II) [Mn(3-MeC6H4COO)2(H2O)2]n with spin canting: rationalization of the magnetic exchange

The crystal structure of Mn(II) carboxylate with 3-methylbenzoate as a bridging ligand [Mn(3-MeC6H4COO)2(H2O)2]n shows a rhomboidal layer, where each pair of neighbor Mn(II) ions are bridged through only one carboxylate group with a syn-anti conformation. The magnetic exchange between neighbor ions is weakly antiferromagnetic (J = −0.52 cm−1, g = 2.04), and at low temperature the system shows spin canting with TB = 3.8 K. Computational studies, based on periodic calculations of the energies of the significant spin states on the magnetic cell and some higher supercells, corroborate the weak AF interaction between the adjacent Mn(II) ions and preclude the negligible effect of frustration caused by very weak interactions between the non-adjacent ions in the magnetic response of the system. The results provide compelling evidence that the observed spin canting is due to the local coordination geometry of the manganese ions leading to two antiferromagnetically coupled subnets with different axial vectors

Phenotypic and genetic characterization of a novel phenotype in pigs characterized by juvenile hairlessness and age dependent emphysema

<p>Abstract</p> <p>Background</p> <p>A pig phenotype characterized by juvenile hairlessness, thin skin and age dependent lung emphysema has been discovered in a Danish pig herd. The trait shows autosomal co-dominant inheritance with all three genotypes distinguishable. Since the phenotype shows resemblance to the integrin β₆-/- knockout phenotype seen in mice, the two genes encoding the two subunits of integrin α_vβ₆, i.e. <it>ITGB6 </it>and <it>ITGAV</it>, were considered candidate genes for this trait.</p> <p>Results</p> <p>The mutated pig phenotype is characterized by hairlessness until puberty, thin skin with few hair follicles and absence of <it>musculi arrectores pili</it>, and at puberty or later localized areas of emphysema are seen in the lungs. Comparative mapping predicted that the porcine <it>ITGB6 </it>and<it>ITGAV </it>orthologs map to SSC15. In an experimental family (n = 113), showing segregation of the trait, the candidate region was confirmed by linkage analysis with four microsatellite markers. Mapping of the porcine <it>ITGB6 </it>and <it>ITGAV </it>in the IMpRH radiation hybrid panel confirmed the comparative mapping information. Sequencing of the <it>ITGB6 </it>and <it>ITGAV </it>coding sequences from affected and normal pigs revealed no evidence of a causative mutation, but alternative splicing of the <it>ITGB6 </it>pre-mRNA was detected. For both <it>ITGB6 </it>and <it>ITGAV </it>quantitative PCR revealed no significant difference in the expression levels in normal and affected animals. In a western blot, ITGB6 was detected in lung protein samples of all three genotypes. This result was supported by flow cytometric analyses which showed comparable reactions of kidney cells from affected and normal pigs with an integrin α_vβ₆monoclonal antibody. Also, immunohistochemical staining of lung tissue with an integrin β₆antibody showed immunoreaction in both normal and affected pigs.</p> <p>Conclusion</p> <p>A phenotype resembling the integrin β₆-/- knockout phenotype seen in mice has been characterized in the pig. The candidate region on SSC15 has been confirmed by linkage analysis but molecular and functional analyses have excluded that the mutated phenotype is caused by structural mutations in or ablation of any of the two candidate genes.</p

Haplotypes on pig chromosome 3 distinguish metabolically healthy from unhealthy obese individuals

We have established a pig resource population specifically designed to elucidate the genetics involved in development of obesity and obesity related co-morbidities by crossing the obesity prone Göttingen Minipig breed with two lean production pig breeds. In this study we have performed genome wide association (GWA) to identify loci with effect on blood lipid levels. The most significantly associated single nucleotide polymorphisms (SNPs) were used for linkage disequilibrium (LD) and haplotype analyses. Three separate haploblocks which influence the ratio between high density lipoprotein cholesterol and total cholesterol (HDL-C/CT), triglycerides (TG) and low density lipoprotein cholesterol (LDL-C) levels respectively were identified on Sus Scrofa chromosome 3 (SSC3). Large additive genetic effects were found for the HDL-C/CT and LDL-C haplotypes. Haplotypes segregating from Göttingen Minipigs were shown to impose a positive effect on blood lipid levels. Thus, the genetic profile of the Göttingen Minipig breed seems to support a phenotype comparable to the metabolic healthy obese (MHO) phenotype in humans

Moving towards malaria elimination in southern Mozambique: Cost and cost-effectiveness of mass drug administration combined with intensified malaria control.

BACKGROUND: As new combinations of interventions aiming at interrupting malaria transmission are under evaluation, understanding the associated economic costs and benefits is critical for decision-making. This study assessed the economic cost and cost-effectiveness of the Magude project, a malaria elimination initiative implemented in a district in southern Mozambique (i.e. Magude) between August 2015-June 2018. This project piloted a combination of two mass drug administration (MDA) rounds per year for two consecutive years, annual rounds of universal indoor residual spraying (IRS) and a strengthened surveillance and response system on the back of universal long-lasting insecticide treated net (LLIN) coverage and routine case management implemented by the National Malaria Control Program (NMCP). Although local transmission was not interrupted, the project achieved large reductions in the burden of malaria in the target district. METHODS: We collected weekly economic data, estimated costs from the project implementer perspective and assessed the incremental cost-effectiveness ratio (ICER) associated with the Magude project as compared to routine malaria control activities, the counterfactual. We estimated disability-adjusted life years (DALYs) for malaria cases and deaths and assessed the variation of the ICER over time to capture the marginal costs and effectiveness associated with subsequent phases of project implementation. We used deterministic and probabilistic sensitivity analyses to account for uncertainty and built an alternative scenario by assuming the implementation of the interventions from a governmental perspective. Economic costs are provided in constant US$2015. RESULTS: After three years, the Magude project averted a total of 3,171 DALYs at an incremental cost of$2.89 million and an average yearly cost of $20.7 per targeted person. At an average cost of$19.4 per person treated per MDA round, the social mobilization and distribution of door-to-door MDA contributed to 53% of overall resources employed, with personnel and logistics being the main cost drivers. The ICER improved over time as a result of decreasing costs and improved effectiveness. The overall ICER was $987 (CI95$1,404/DALY averted, three times the gross domestic product (GDP) per capita of Mozambique, but above the threshold of interventions considered highly cost-effective (one time the GDP per capita or $468/DALY averted) and above the recently suggested thresholds based on the health opportunity cost ($537 purchasing power parity/ DALY averted). A significantly lower ICER was obtained in the implementation scenario from a governmental perspective ($441/DALY averted). CONCLUSION: Despite the initial high costs and volume of resources associated with its implementation, MDA in combination with other existing malaria control interventions, can be a cost-effective strategy to drastically reduce transmission in areas of low to moderate transmission in sub-Saharan Africa. However, further studies are needed to understand the capacity of the health system and financial affordability to scale up such strategies at regional or national level