Mapping of quantitative trait loci for clinical–chemical traits in swine

Clinical–chemical traits are diagnostic parameters essential for characterization of health and disease in veterinary practice. The traits show significant variability and are under genetic control, but little is known about the fundamental genetic architecture of this variability, especially in swine. We have identified QTL for alkaline phosphatase (ALP), lactate (LAC), bilirubin (BIL), creatinine (CRE) and ionized sodium (Na⁺), potassium (K⁺) and calcium (Ca⁺⁺) from the serum of 139 F₂ pigs from a Meishan/Pietrain family before and after challenge with Sarcocystis miescheriana , a protozoan parasite of muscle. After infection, the pigs passed through three stages representing acute disease, subclinical disease and chronic disease. Forty-two QTL influencing clinical–chemical traits during these different stages were identified on 15 chromosomes. Eleven of the QTL were significant on a genome-wide level; 31 QTL were chromosome-wide significant. QTL showed specific health/disease patterns with respect to the baseline values of the traits as well as the values obtained through the different stages of disease. QTL influencing different traits at different times were found primarily on chromosomes 1, 3, 7 and 14. The most prominent QTL for the investigated clinical–chemical traits mapped to SSC3 and 7. Baseline traits of ALP, LAC, BIL, Ca⁺⁺ and K⁺ were influenced by QTL regions on SSC3, 6, 7, 8 and 13. Single QTL explained up to 21.7% of F₂ phenotypic variance. Our analysis confirms that variation of clinical–chemical traits is associated with multiple chromosomal regions.     

Every plant for himself; the effect of a phenolic monoterpene on germination and biomass of Thymus pulegioides and T. serpyllum

Thyme plants are known for their production of aromatic oils, whose main component is terpenes. The plants leach terpenes to their surroundings and thereby affect the seed germination and biomass of associated plants, but also potentially themselves. A variation in the dominant terpenes produced by thyme plants is found both within and among species. In Denmark two thyme species (Thymus pulegioides and T. serpyllum) are naturally occurring. The essential oil of T. pulegioides in Denmark is mainly dominated by one monoterpene; ‘carvacrol’. In contrast, the essential oil of T. serpyllum constitutes a mix of two–four different types of terpenes, both mono‐ and sesqui‐terpenes. As the effects of terpenes on plant performance can vary with the type of terpene, and in order to study species‐specific responses, we examined how the dominating T. pulegioides monoterpene ‘carvacrol’ affected germination and growth of both T. pulegioides and T. serpyllum. We compared the performance of seeds and seedlings of both thyme species on soil treated with carvacrol versus control soil. We found no effect of treatment on germination, but we detected a highly significant effect of treatment on seedling biomass. For both thyme species, seedling biomass was significantly higher on terpene soil compared to control soil, suggesting a general adaptation to the presence of terpenes in the soil for both thyme species. Moreover, while no difference in seedling biomass between species on control soil was found, T. pulegiodes seedlings were significantly larger than T. serpyllum when grown on soil treated with its ‘home’ terpene, suggesting an additional species specific response. Dividing the biomass into aboveground and root biomass showed that the increased biomass on terpene‐soil was due to increased aboveground biomass, whereas no difference in root biomass was detected among treatments and species. We discuss whether this response may be caused by an adaptation to a predictable terpene‐mediated alteration in nitrogen‐availability.     

Clinal differentiation during invasion: <Emphasis Type="Italic">Senecio inaequidens</Emphasis> (Asteraceae) along altitudinal gradients in Europe

The dynamics of plant population differentiation may be integral in predicting aspects of introduced species invasion. In the present study, we tested the hypothesis that European populations of Senecio inaequidens (Asteraceae), an invasive species with South African origins, differentiated during migration from two independent introduction sites into divergent altitudinal and climatic zones. We carried out 2 years of common garden experiments with eight populations sampled from Belgian and ten populations from French altitudinal transects. The Belgian transect followed a temperature and precipitation gradient. A temperature and summer drought gradient characterized the French transect. We evaluated differentiation and clinal variation in plants germinated from field-collected seed using the following traits: days to germination, days to flowering, height at maturity, final plant height and aboveground biomass. Results showed that S. inaequidens populations differentiated in growth traits during invasion. During the 1st year of sampling, the results indicated clinal variation for growth traits along both the Belgium and French altitudinal transects. Data from the 2nd year of study demonstrated that with increasing altitude, a reduction in three growth traits, including plant height at maturity, final plant height and aboveground biomass, was detected along the French transect, but no longer along the Belgian one. Phenological traits did not exhibit a clear clinal variation along altitudinal transects. The possible evolutionary causes for the observed differentiation are discussed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Effects of ethanol on pancreatic beta-cell death: interaction with glucose and fatty acids

Western lifestyle plays an important role in the prevalence of type 2 diabetes by causing insulin resistance and pancreatic β-cell dysfunction, a prerequisite for the development of diabetes. High fat diet and alcohol are major components of the western diet. The aim of the present study was to investigate the effects of ethanol and fatty acids on β-cell survival and metabolism. We treated the rat β-cell line RINm5F with ethanol, a mixture of palmitic and oleic acids, or both. Reactive oxygen species (ROS) were determined by (5-(and-6)-chloromethyl-2′,7′-dichlorodihydrofluorescein diacetate) (CM-H2DCFDA) fluorescence assay, and mitochondrial activity was assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) reduction assay and by determining ATP production. Cell viability was assessed with a cell counter and trypan blue exclusion, and the mode of cell death by Hoechst33342 and propidium iodide staining. With both ethanol and fatty acid treatments, MTT reduction and ATP production decreased, whereas ROS production increased. Ethanol treatment had no effect on cell number, whereas fatty acid treatment reduced the cell number. Cell incubation with ethanol, fatty acids, or both increased the number of Hoechst 33342-positive nuclei. However, the majority of nuclei from fatty acid-treated cells were stained with propidium iodide, indicating a loss of plasma membrane integrity. We conclude that both ethanol and fatty acids generate cellular oxidative stress, and affect mitochondrial function in RINm5F β-cells. However, ethanol causes β-cell death by apoptosis, whereas fatty acids cause cell death predominantly by necrosis. It is not known whether these results are applicable to human β-cells.     

Synthesis and cytotoxic activity of 5,6-heteroaromatically annulated pyridine-2,4-diamines

A series of 5,6-heteroaromatically annulated pyridine-2,4-diamines have been synthesized and their in vitro cytotoxic activities evaluated against six human cancer cell lines. Benzo[g] annulated pyrido[2,3-b]indolediamines 7a–b and 8 showed relatively high cytotoxic activity as well as most of the diamines with pyrrolo[2,3-b]pyridine 17, thieno[2,3-b]pyridine and furo[2,3-b]pyridine 26–28, 1,8-naphthyridine 32 and 34 and benzo[h]quinoline 37 skeletons. Surprisingly, pyrido[2,3-b]indolediamines 13 and 14 without benzo[g] annulation were inactive. None of the new compounds were as potent as ellipticine, the reference compound.     

Classification of hybrid and altered Vibrio cholerae strains by CTX prophage and RS1 element structure

Analysis of the CTX prophage and RS1 element in hybrid and altered Vibrio cholera O1 strains showed two classifiable groups. Group I strains contain a tandem repeat of classical CTX prophage on the small chromosome. Strains in this group either contain no element(s) or an additional CTX prophage or RS1 element(s) on the large chromosome. Group II strains harbor RS1 and CTX prophage, which has an E1 Tor type rstR and classical ctxB on the large chromosome.