Aberrant conjunctival stricture and overgrowth in the rabbit

Six dwarf rabbits with unilateral (n = 2) and bilateral (n = 4) aberrant conjunctival growth underwent surgical correction. The applied technique involved centrifugal incisions of the overgrowing conjunctiva to the limbus and a transpalpebral fixation of the conjunctiva. In this way the conjunctival fornix was reconstructed. No relapses were noted within the observation period (5-72 months).     

Genetic variation in leaf and stem glucosinolates in resynthesized lines of winter rapeseed (<Emphasis Type="Italic">Brassica napus</Emphasis> L.)

Glucosinolates are secondary components characteristic for the Brassicaceae with complex biological functions. Glucosinolates in the seeds are anti-nutritive when feeding animals and their inheritance have been extensively investigated. Much less is known about the genetics of glucosinolates in leaves and stems, which may attract some insects, while repelling others. They may also inhibit bacterial processes of importance when using green biomass for the production of biogas. The objective of this study was to analyse the genetic variation of total and individual glucosinolates in the green material of rapeseed. For this 28 resynthesized winter rapeseed lines were tested at two locations. There was a large variation in leaf glucosinolate content between 0.10 and 4.75 μmol/g dry matter. The predominant leaf glucosinolates are the alkenyle glucosinolates progoitrin, gluconapin and glucobrassicanapin. The line R53 is exceptional, while combining a relative high content of the indole glucosinolate glucobrassicin with low alkenyle glucosinolates in the leaves. The total glucosinolate concentration in the stems and leaves is not correlated with the seed glucosinolate concentrations. Heritabilities are above h2 = 0.60 for progoitrin, h2 = 0.65 for gluconapin, h2 = 0.30 for glucobrassicanapin and h2 = 0.52 for total glucosinolate content in the leaves. In conclusion, resynthesized rapeseed is an important genetic resource to modify the leaf glucosinolate content and composition of rapeseed.     

The alarmin interleukin-33 drives protective antiviral CD8⁺ T cell responses

Pathogen-associated molecular patterns decisively influence antiviral immune responses, whereas the contribution of endogenous signals of tissue damage, also known as damage-associated molecular patterns or alarmins, remains ill defined. We show that interleukin-33 (IL-33), an alarmin released from necrotic cells, is necessary for potent CD8(+) T cell (CTL) responses to replicating, prototypic RNA and DNA viruses in mice. IL-33 signaled through its receptor on activated CTLs, enhanced clonal expansion in a CTL-intrinsic fashion, determined plurifunctional effector cell differentiation, and was necessary for virus control. Moreover, recombinant IL-33 augmented vaccine-induced CTL responses. Radio-resistant cells of the splenic T cell zone produced IL-33, and efficient CTL responses required IL-33 from radio-resistant cells but not from hematopoietic cells. Thus, alarmin release by radio-resistant cells orchestrates protective antiviral CTL responses.     

Viability of mountain caribou in British Columbia, Canada: Effects of habitat change and population density

Population viability analyses (PVA) are frequently employed to develop recovery plans and inform management of endangered species. Translating results from PVA into meaningful management recommendations often depends on an understanding of how population parameters change with environmental conditions as well as population density. The decline of mountain caribou (Rangifer tarandus caribou) in British Columbia, Canada, is believed to be caused by apparent competition with alternative prey species following changes to the forest age structure from timber harvest and wildfire. In addition, populations have been shown to decline at faster rates at low population density. To evaluate the potential effects of habitat change and population density on population persistence, we used stochastic projection models for 10 distinct populations varying in initial size from <10 to approximately 150 females. In an initial model, we used estimates of vital rates based on information sampled from >350 radiocollared caribou between 1984 and 2004. We then compared the results of the initial model to a set of models that evaluated the effects of habitat conditions and population density via their expected relationships to female adult survival. Assuming that vital rates remain constant over a 200-year time frame, only three populations have high probabilities (>0.95) of extinction. When models incorporate the declines in adult female survival know to occur with increasing proportions of young forest and declining population densities, all 10 populations are predicted to decline to extinction within <200 years. Based on our results, we suggest that PVA models that fail to incorporate the effects of changes in vital rates with habitat and population density may lead to overly optimistic assessments of the probability of population persistence in endangered species.     

Genetic variability and interrelationship of traits in the industrial oil crop Vernonia galamensis

Vernonia galamensis is a wild plant from the family Asteraceae which is endemic to East Africa and has the potential to become a new oil crop for industrial uses. Its seed oil is rich in vernolic acid, a fatty acid of high interest for oleochemical applications. However, a breeding program for Vernonia galamensis cultivars with high seed and oil yields requires knowledge about the genetic variability of traits that influence seed and oil production. This study was undertaken to examine phenotypic and genotypic variability, broad-sense heritability, genetic advance under selection and interrelationships of agronomic and seed quality traits. A total of 122 Vernonia accessions, 115 collected from different regions of Ethiopia and seven introduced, were grown at two locations in Ethiopia (Alemaya and Babile), in 2001/2002 and were analyzed for 20 traits including phenology, yield, yield components, and seed quality with special emphasis on fatty acid composition. The collections exhibited significant variation for all traits except for days to emergence. Genotypes and locations interacted significantly (P 0.01) for all traits. Broad-sense heritability estimates ranged from 11% (for days to emergence) up to 79% (for days to maturity). Expected genetic advance was between 1.3% (for days to emergence) and 44.8% (for seed oil yield). Genetic correlation analysis revealed that seed yield per plant is highly and positively correlated with seed weight and head number; highly significant and negative correlations (r = –0.59, –0.82, –0.85, and –0.89) were found between vernolic acid and palmitic, stearic, oleic, and linoleic acid, respectively. Highly significant positive correlations (r = 0.55, 0.44, and 0.36) were observed between vernolic acid and oil content, meal protein content and seed oil yield, respectively. Path-coefficient analysis indicated seed weight and secondary head number to be the most important components of seed yield per plant. Vernolic acid, oleic acid and linoleic acid had positive direct effects and stearic acid had a negative direct effect on oil content. The direct positive effect of oleic acid on oil content was, however, compensated by the negative indirect effects of stearic and vernolic acid resulting in a negative correlation (r = –0.60) between oleic acid and oil content. These observations will support the selection of accessions with high seed and oil yield, high meal protein contents, and high vernolic acid content.     

Genetic variation of tocopherol content in a germplasm collection of Brassica napus L.

The genetic variation for tocopherol contents was investigated in a very divergent collection of 87 winter rapeseed genotypes grown in the greenhouse and in two years in the field. Genotypic and environmental effects were highly significant for alpha-, gamma- and total tocopherol contents and the alpha-/gamma-tocopherol ratio. Field and greenhouse environments differed significantly (p < 0.001) for tocopherol traits, with greenhouse means up to 19% higher than field means. Alpha-tocopherol content ranged from 63 to157 mg kg^-1 seed, gamma-tocopherol content from 114 to 211 mg kg^-1 seed, total tocopherol content from 182 to367 mg kg^-1 seed, and the alpha-/gamma-tocopherol contents ratio from0.36 to 1.23. The resynthesized lines often have a remarkably low alpha-tocopherol content and consequently a low alpha-/gamma-tocopherol contents ratio. The lines with altered fatty acid composition displayed the highest variation for both tocopherol content and composition. No significant differences were observed among groups with different seed quality types [00], [0+] and [++]. Total tocopherol content was not correlated with the alpha-/gamma-tocopherol ratio, indicating that total tocopherol content is independent from tocopherol composition. Alpha- and gamma-tocopherol contents were also not correlated. Gamma-tocopherol contents showed a significant positive correlation with oil content (r = 0.34^**). This revised version was published online in July 2006 with corrections to the Cover Date.     

Factors that contribute to genetic variation for nutrient efficiency of crop plants

Genetic variation in nutrient efficiency may be attributed to two multifactorial components: (i) genotypes may differ in the efficiency with which the nutrients in the plant are utilized to produce yield (utilization efficiency) and/or (ii) they may differ in their effectiveness in absorbing nutrients from the soil (uptake efficiency). This contribution surveys major aspects of physiological and morphological factors affecting N-and P-efficiency. The potential importance of the various factors is discussed and exemplified mainly by own experimental work.     

GlyR alpha3: an essential target for spinal PGE2-mediated inflammatory pain sensitization

Prostaglandin E2 (PGE2) is a crucial mediator of inflammatory pain sensitization. Here, we demonstrate that inhibition of a specific glycine receptor subtype (GlyR alpha3) by PGE2-induced receptor phosphorylation underlies central inflammatory pain sensitization. We show that GlyR alpha3 is distinctly expressed in superficial layers of the spinal cord dorsal horn. Mice deficient in GlyR alpha3 not only lack the inhibition of glycinergic neurotransmission by PGE2 seen in wild-type mice but also show a reduction in pain sensitization induced by spinal PGE2 injection or peripheral inflammation. Thus, GlyR alpha3 may provide a previously unrecognized molecular target in pain therapy.     

The complete genome sequence of Propionibacterium acnes, a commensal of human skin

Propionibacterium acnes is a major inhabitant of adult human skin, where it resides within sebaceous follicles, usually as a harmless commensal although it has been implicated in acne vulgaris formation. The entire genome sequence of this Gram-positive bacterium encodes 2333 putative genes and revealed numerous gene products involved in degrading host molecules, including sialidases, neuraminidases, endoglycoceramidases, lipases, and pore-forming factors. Surface-associated and other immunogenic factors have been identified, which might be involved in triggering acne inflammation and other P. acnes-associated diseases.     

Improvement of Sclerotinia sclerotiorum resistance in Brassica napus by using B. oleracea

Sclerotinia stem rot is one of the most serious diseases in rapeseed (Brassica napus) due to the lack of resistance sources. A high level of resistance was reported in Brassica oleracea cytodeme, one of parental species of rapeseed. In this study, a panel of 55 resynthesized lines of B. napus (RS lines) derived from seven wild and two cultivated types of B. oleracea was evaluated for Sclerotinia resistance over 2 years. Relative to ‘Zhongyou 821’, a cultivar of B. napus with partial resistance against S. sclerotiorum, RS lines exhibited stronger stem resistance. Although the resistant level of RS lines was lower than that of corresponding parental B. oleracea, a moderate correlation between resistance of RS line and corresponding parental B. oleracea type was found both for leaf (r = 0.74, P = 0.02) and stem (r = 0.69, P = 0.04). Our data suggests that the RS lines are important resources to improve Sclerotinia resistance of current rapeseed. A breeding strategy is discussed to enhance the Sclerotinia resistance of rapeseed by using B. oleracea.