Egg shell quality,clutch size and hatching success of the great tit (Parus major) and the pied flycatcher (Ficedula hypoleuca) in an air pollution gradient

Egg shell thickness, egg volume, clutch size and hatching success of Parus major and Ficedula hypoleuca were studied at 14 study sites around a copper smelter complex in Harjavalta, south-west Finland, in 1991–1993. In 1991–1992 unhatched eggs were collected to measure shell quality. F. hypoleuca was more susceptible to pollutants than P. major, the response of which was weaker in all aspects studied. Egg shells of F. hypoleuca were about 17% thinner and eggs were about 8% smaller in volume near the factory than at a distance of 10 km. The clutch size of F. hypoleuca was significantly smaller and hatching success markedly lower at a study site next to the factory complex than at all other sites. In P. major, variation in shell thickness and egg volume was not significantly related to the distance from the pollution source. Clutch size and hatching success of P. major did not significantly differ among study sites, although the trend in hatching success was in the same direction as in F. hypoleuca. Clutches of both species contained less shell material and both species had more nests without eggs near the factory than further away. The surface structure of the eggshells was studied by scanning electron microscope. Especially in F. hypoleuca, the egg shell surface was more rough and porous near the factory. The roles of Ca and heavy metals in shell thinning are discussed.     

Genotypic variation in yellow autumn leaf colours explains aphid load in silver birch

? It has been suggested that autumn-migrating insects drive the evolution of autumn leaf colours. However, evidence of genetic variation in autumn leaf colours in natural tree populations and the link between the genetic variation and herbivore abundances has been lacking. ? Here, we measured the size of the whole aphid community and the development of green-yellow leaf colours in six replicate trees of 19 silver birch (Betula pendula) genotypes at the beginning, in the middle and at the end of autumn colouration. We also calculated the difference between green leaf and leaf litter nitrogen (N) and estimated the changes in phloem sap N loading. ? Autumn leaf colouration had significant genetic variation. During the last survey, genotypes that expressed the strongest leaf reflectance 2-4 wk earlier had an abundance of egg-laying Euceraphis betulae females. Surprisingly, the aphid community size during the first surveys explained N loss by the litter of different birch genotypes. ? Our results are the first evidence at the tree intrapopulation genotypic level that autumn-migrating pests have the potential to drive the evolution of autumn leaf colours. They also stress the importance of recognizing the role of late-season tree-insect interactions in the evolution of herbivory resistance.     

The effects of diet quality and quantity on plumage colour and growth of great tit Parus major nestlings: a food manipulation experiment along a pollution gradient

The yellow carotenoid-based plumage coloration of great tit Parus major nestlings is found to be paler in polluted and urban environments. Because carotenoid pigmentation is often considered to be a condition dependent trait in birds we wanted to find out whether food-limitation and poor nestling condition could explain the pale plumage colour in a polluted area. P. major nestlings were supplemented with variable diets along a well known heavy metal pollution gradient around a copper smelter: two food treatments with carotenoids, one food treatment with little carotenoid and one unsupplemented control. Our field experiment showed that nestlings in the polluted area grew better with carotenoid rich diets, while such effect was not found in the unpolluted area. Nestlings showed higher plasma carotenoid (lutein) levels and higher plumage carotenoid chroma values in the unpolluted area than in the polluted area. However, plasma lutein levels or plumage colour were not associated with heavy metal levels in nestling faeces (a proxy for dietary exposure). Our results provide only weak evidence for carotenoid-based colouration to be condition-dependent in great tit nestlings as we found a positive relationship between body mass and carotenoid chroma in the non-supplemented control group only. The positive relationship between body mass and plumage colour intensity is more likely to be produced by the fact that good availability of caterpillars, an important food source for P. major, also means a good availability of carotenoids to nestlings. Our results suggest that main reason for pale nestling plumage in the polluted area is lower quality invertebrate food, and not nutrition-related oxidative stress.     

The involvement of mitochondria and the caspase-9 activation pathway in rituximab-induced apoptosis in FL cells

Despite the wide use of anti-CD20 antibody rituximab in the cancer treatment of B cell malignancies, the signalling pathways of CD20-induced apoptosis are still not understood. By using dominant negative (DN)-caspase-9 overexpressing follicular lymphoma cells we demonstrated that the activation of caspase-9 was essential for rituximab-mediated apoptosis. The death receptor pathway mediated by caspase-8 activation was not involved in rituximab-mediated apoptosis since overexpression of FLIP_short or FLIP_long proteins, inhibitors of caspase-8 activation, could not inhibit rituximab-induced apoptosis. However, the death receptor pathway activation by anti-Fas antibodies showed an additive effect on rituximab-induced apoptosis. The stabilisation of the mitochondrial outer membrane by Bcl-x_L overexpression inhibited cell death, showing the important role of mitochondria in rituximab-induced apoptosis. Interestingly, the rituximab-induced release of cytochrome c and collapse of mitochondrial membrane potential were regulated by caspase-9. We suggest that caspase-9 and downstream caspases may feed back to mitochondria to amplify mitochondrial disruption during intrinsic apoptosis.     

In situ effector mechanisms in rat kidney allograft rejection. I. Characterization of the host cellular infiltrate in rejecting allograft parenchyma.

The infiltrating inflammatory cells were recovered with collagenase and DNase from rejecting rat kidney allografts and autografts in conditions where the enzyme treatment did not affect the expression of subclass-specific surface markers. As the differential distribution of the inflammatory cells in the dispersate was similar to the distribution of inflammatory cells in tissue imprints, and as any major blood contamination was excluded, we consider the results representative of the composition of the in situ infiltrate. At the peak of rejection on Day 6 after the transplantation, approximately 30% monocytes, 17% macrophages, 31% lymphocytes, 6% (T) lymphoblasts, and 10% (B) plasmablasts and plasma cells were present in the graft. The blast cell response, pathognomonic to immune activation, was less prominent in the recipient spleen, blood, and lymph nodes. Twenty-three percent of the infiltrating lymphocytes expressed the (T-cell-specific) Pta.A.1 surface antigen(s) and 14% were surface Ig positive. The remaining lymphocytes were double-negative “null cells.” In preparative cell electrophoresis most of the allograft-infiltrating lymphocytes carried the low electrophoretic mobility, characteristic to resting B cells. Approximately 70% of allograft-infiltrating macrophages and 50% of infiltrating monocytes but only 30% of the monocytes present in the recipient spleen expressed the Fc receptor to IgG, suggesting an activation (or increase in avidity) of this receptor during the influx of mononuclear cells into the site of inflammation and during maturation of monocytes into tissue macrophages. There was a strong in situ proliferative activity, far stronger than in the central lymphatic system of the recipient rat. After 1 hr in vivo pulse labeling with [3H]thymidine 24% of the infiltrating inflammatory cells carried the label. Most of the labeled cells were blasts or lymphocytes, but a small albeit distinct number of labeled monocytes were also present in situ. In contrast to the recipient spleen, where most of the labeled lymphoid cells had a high electrophoretic mobility of resting T cells, in the infiltrate most of the labeled lymphoid cells had a slow mobility of resting B cells.     

Simultaneous determination of nicotine and cotinine in plasma using capillary column gas chromatography with nitrogen-sensitive detection

A rapid and sensitive method is described for the simultaneous determination of nicotine and its principal metabolite, cotinine, in plasma. A one-step extraction procedure is employed and the quantitative analyses are performed by capillary column gas chromatography using a thermionic specific detector. Other special measures to avoid contamination from external sources such as atmosphere, solvents and laboratory equipment, which constitutes the major limiting factor of nicotine assay, were also undertaken. The structural analogues of nicotine and cotinine, N-methylanabasine and N-ethylnorcotinine, are used as internal standards. Moreover, a micromethod, which requires only 0.1 ml of plasma and found to be suitable for analysis of cotinine in finger-tip samples of blood, is described. Linearity over the concentration ranges 5–100 ng of nicotine per ml of plasma and 5–500 ng of cotinine per ml of plasma is demonstrated. The precision of the method has been investigated by determining the reproducibility at different levels of nicotine and cotinine within the working ranges, for both 1-ml and 0.1-ml samples of plasma.     

Biodegradation efficiency of functionally important populations selected for bioaugmentation in phenol- and oil-polluted area

Denaturing gradient gel electrophoresis of amplified fragments of genes coding for 16S rRNA and for the largest subunit of multicomponent phenol hydroxylase (LmPH) was used to monitor the behaviour and relative abundance of mixed phenol-degrading bacterial populations (Pseudomonas mendocina PC1, P. fluorescens strains PC18, PC20 and PC24) during degradation of phenolic compounds in phenolic leachate- and oil-amended microcosms. The analysis indicated that specific bacterial populations were selected in each microcosm. The naphthalene-degrading strain PC20 was the dominant degrader in oil-amended microcosms and strain PC1 in phenolic leachate microcosms. Strain PC20 was not detectable after cultivation in phenolic leachate microcosms. Mixed bacterial populations in oil-amended microcosms aggregated and formed clumps, whereas the same bacteria had a planktonic mode of growth in phenolic leachate microcosms. Colony hybridisation data with catabolic gene specific probes indicated that, in leachate microcosms, the relative proportions of bacteria having meta (PC1) and ortho (PC24) pathways for degradation of phenol and p-cresol changed alternately. The shifts in the composition of mixed population indicated that different pathways of metabolism of aromatic compounds dominated and that this process is an optimised response to the contaminants present in microcosms.