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  • 1
    Electronic Resource
    Electronic Resource
    Effects of enhanced UVB radiation on a marine benthic diatom mat (1997)
    Springer
    Marine biology 128 (1997), S. 171-179 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In order to study the ecophysiological response of a natural diatom-dominated microbial mat to an enhanced level of ultraviolet-B radiation (UVBR), intact sediment cores from a shallow microtidal bay on the Swedish west coast were incubated in an outdoor flow-through system and exposed to either no UVBR or to an artificially enhanced level of UVBR. The microbial mat was cohesive and dominated by the large (≈ 400 μm) motile diatom Gyrosigma balticum. Functional response to UVBR was assessed by measuring carbon fixation (14C) and allocation of photosynthetic products. Sediment oxygen microprofiles were measured as indicators of the balance between the photosynthetic and respiratory activity of the community. Structural variables included biomass and composition of microalgae, pigment composition (HPLC), content of UV-absorbing compounds, and composition of fatty acids. An enhanced level of UVBR resulted in significant functional changes in the microalgal community. Significantly decreased carbon fixation and lower net oxygen production (as calculated from oxygen microprofiles) suggest that primary productivity in the type of microbial mat studied is potentially sensitive to an enhanced level of UVBR. The pattern of carbon allocation hinted a change as to the photosynthetically active part of the community when exposed to UVBR, indicating a differential sensitivity among algal cells. Despite significant functional effects, pigment or algal composition were not significantly affected by enhanced UVBR. The concentration of UV-absorbing compounds was low and did not increase at UVBR exposure. Due to the short duration of the experiment (4 d), a change in algal biomass or composition was not to be expected. Moreover, the thickness of the sampled sediment layer, may have contributed to the lack of observed structural effects of enhanced UVBR. Visual observations suggested that UVBR affected the motility of G. balticum. This study, as well as other experiments with a similar diatom mat, suggest that vertical migration is a key mechanism to be further studied in relation to UVBR exposure of diatom-dominated microbial mats.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002270050080
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  • 2
    Electronic Resource
    Electronic Resource
    Effects of UVB radiation in a microbenthic community of a marine shallow-water sandy sediment (1998)
    Springer
    Marine biology 132 (1998), S. 335-345 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The role of ambient and enhanced ultraviolet-B radiation (UVB; 280 to 315 nm) in a natural sand-associated microbenthic community was studied in a 3-week experiment by incubating intact sediment cores from a shallow bay in an outdoor flow-through system with 27 aquaria. After sampling of initial cores, the remaining cores (one per aquarium) were given one of three treatments: no, ambient, and moderately enhanced UVB, and sampled, nine at a time, after 5, 12, and 19 d. The response of the community was studied by analysing algal and meiofaunal composition and biomass, chlorophyll a content, composition of pigments and fatty acids, and content of UV-absorbing compounds (state variables), as well as carbon fixation and allocation, and bacterial productivity (rate variables). Among rate variables, significant effects of UVB-treatments were found for carbon fixation and allocation, while bacterial productivity was not affected. For state variables, a significant response was observed for the composition of microalgae and fatty acids, and for chlorophyll a content. The effect of treatments was mainly observed as differences in development with time (two-way analysis of variance, treatment × time interaction). Towards the end of the experiment, the no-UVB treatment most often differed from one or both of the two treatments with UVB exposure, the latter showing lower values. There were marked successional changes in the community, irrespective of treatment. The microalgal community changed from being dominated by coccoid cyanobacteria and epipsammic diatoms to a dominance of epipelic diatoms and filamentous cyanobacteria. The pattern of carbon allocation, as well as an increased C/N ratio of the sediment, suggested limitation of growth, perhaps by nutrients, at the end of the experiment. This may possibly have acted synergistically with UVB exposure to create the treatment effects. The new knowledge gained from our experiment is that ambient UVB can exert a stress on the function of sand-associated microbenthic communities in shallow waters and that this effect coincides with structural differences in the community. More experiments in natural or semi-natural systems are needed to allow better prediction of microbenthic community-level responses to UVB.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002270050399
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  • 3
    Electronic Resource
    Electronic Resource
    High-pressure liquid chromatographic determination of acetylsalicylic acid, salicylic acid, diflunisal, indomethacin, indoprofen and indobufen (1981)
    Springer
    European journal of clinical pharmacology 20 (1981), S. 375-378 
    Details
    ISSN: 1432-1041
    Keywords: acetylsalicylic acid ; diflunisal ; indomethacin ; salicylic acid ; indoprofen ; indobufen ; high-pressure liquid chromatography ; plasma level
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A high-pressure liquid chromatographic technique was developed which allowed concurrent measurement of acetylsalicylic acid (ASA) and salicylic acid (SA) in plasma. ASA was extensively deacetylated to SA not only in vivo but also in vitro, even in frozen plasma. The in vitro conversion could be prevented by physostigmine. In vivo, ASA was eliminated within few hours, whereas SA was continuously present following daily administration of conventional doses of ASA. A slight modification of a similar method, originally developed for naproxen determination [9], was found appropriate for measurement of the SA derivative diflunisal, of two non-SA antiinflammatory agents, indomethacin and indoprofen, and of a related anti-platelet agent, indobufen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00615408
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  • 4
    Electronic Resource
    Electronic Resource
    Improvements in the liquid chromatography-flame atomic absorption spectrometric determination of organotin compounds using a nebulizer interface
    Amsterdam : Elsevier
    Spectrochimica Acta Part B: Atomic Spectroscopy 44 (1989), S. 589-595 
    Details
    ISSN: 0584-8547
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0584-8547(89)80138-7
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  • 5
    Electronic Resource
    Electronic Resource
    An efficient synthesis of (+)-anatoxin-a.
    Amsterdam : Elsevier
    Tetrahedron: Asymmetry 3 (1992), S. 1263-1270 
    Details
    ISSN: 0957-4166
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/S0957-4166(00)82084-4
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  • 6
    Electronic Resource
    Electronic Resource
    CD14 and development of atopic disease at 2 years of age in children with atopic or non-atopic mothers (2003)
    Oxford, UK : Blackwell Science Ltd
    Clinical & experimental allergy 33 (2003), S. 0 
    Details
    ISSN: 1365-2222
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background CD14, a myeloid cell marker and LPS receptor has been acclaimed to play a role in development and manifestation of atopic allergy, as the gene encoding CD14 is located in a chromosomal region linked to total IgE levels and atopic disease.Objective To investigate the levels of soluble (s) and membrane bound (m) CD14 in cord blood and at 2 years of age from children with atopic or non-atopic mothers and relate these parameters to atopy development at 2 years of age.Methods Blood samples were collected at delivery (cord blood) and at 2 years of age among infants with atopic (n = 41) and non-atopic (n = 32) mothers. Blood samples were also obtained from mothers at the same occasions. Levels of sCD14 and total IgE were measured in plasma, and percentages of CD14+ cells were measured in cord and peripheral blood mononuclear cells.Results We observed significant differences in sCD14 levels in cord blood, where children with atopic mothers had the highest levels. The same pattern could be observed in the mothers at delivery. At 2 years of age no significant differences in sCD14 levels were observed between children with atopic mothers and children with non-atopic mothers and no association between sCD14 and atopic disease was found. Further, we observed large differences in sCD14 and mCD14 with respect to age, where newborns displayed a higher frequency of CD14+ cells compared with the 2-year-olds and the mothers. The reverse was observed for sCD14, with significantly lower values in cord blood than those seen in the 2-year-olds and mothers.Conclusion Based on our findings, we suggest that CD14 could be involved in the regulation of IgE production, but that it might also be important for the maturation and development of the neonatal immune system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2222.2003.01629.x
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  • 7
    Electronic Resource
    Electronic Resource
    Low numbers of interleukin-12-producing cord blood mononuclear cells and immunoglobulin E sensitization in early childhood (2004)
    Oxford, UK : Blackwell Science Ltd
    Clinical & experimental allergy 34 (2004), S. 0 
    Details
    ISSN: 1365-2222
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background Successful pregnancies are associated with skewing towards a Th2 cytokine profile. Cytokine responses to allergens can be detected in cord blood mononuclear cells (CBMC), suggesting allergen priming already in utero.Objective To investigate the cytokine profile in CBMC after in vitro stimulation with allergens and to relate the responses to the outcome in terms of allergic disease at 2 years of age.Methods CBMC were isolated from 82 children. The responses to ovalbumin (OVA), birch, cat and phytohaemagglutinin (PHA) were investigated by the ELISpot technique. The numbers of IFN-γ-, IL-4- and IL-12-producing CBMC were counted for each stimulation. The children were followed prospectively; skin prick test (SPT) and RAST towards food and inhalant allergens were assessed at 24 months of age.Results Sixteen (19.5%) children were classified as IgE sensitized (positive SPT; 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:09547894:CEA1896:ges" location="ges.gif"/〉3 mm and/or RAST; 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:09547894:CEA1896:ges" location="ges.gif"/〉0.35 kUA/L). The numbers of IL-12-producing CBMC after stimulation with birch, OVA and cat were lower among IgE-sensitized children, statistically significant for cat. IFN-γ-producing cells, did not differ in numbers between the sensitized and non-sensitized children. Children who had atopic eczema/dermatitis syndrome (AEDS) during the observation (n=53) had significantly lower numbers of IFN-γ-producing CBMC after stimulation with OVA and cat than their non-AEDS counterparts.Conclusions Although the numbers of infants in our study are limited our data suggest that a low number of IL-12-producing CBMC is associated with IgE sensitization during early childhood and that a reduced number of IFN-γ-producing CBMC promotes the development of AEDS during the first 2 years of life.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2222.2004.01896.x
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  • 8
    Electronic Resource
    Electronic Resource
    Temporal variation in the drift of plant litter and propagules in a small boreal river (2002)
    Oxford, UK : Blackwell Science Ltd
    Freshwater biology 47 (2002), S. 0 
    Details
    ISSN: 1365-2427
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: SUMMARY 1. Rivers are linear ecosystems across landscapes with an effective transport of organisms, sediment and organic matter. Dispersal is studied mostly during single events and for single species, and there is little knowledge on how the drift of plant litter and propagules varies within and between years for entire communities.2. We used floating traps for collecting waterborne plant litter and propagules in a small boreal river over 2 years. We installed the traps at four different locations along the river, and emptied them at least once a week during the ice-free season. We analysed propagule content by sorting and identifying species and through germination tests on bare soil.3. In total, we recorded at least 54 taxa in the samples, and the highest density recorded in one sample was 5000 propagules per 100 g litter (dry weight). Large temporal variations in litter and propagule transport were revealed, both within and between years.4. The longitudinal pattern was consistent between years, with an increasing mass of litter and number of propagule taxa downstream. The results highlight the importance of the temporal and longitudinal dimensions in river management.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2427.2002.00925.x
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  • 9
    Electronic Resource
    Electronic Resource
    Levels of soluble CD30 in cord blood and peripheral blood during childhood are not correlated with the development of atopic disease or a family history of atopy (2003)
    Oxford, UK : Blackwell Science Ltd
    Clinical & experimental allergy 33 (2003), S. 0 
    Details
    ISSN: 1365-2222
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background The CD30 molecule has been linked to Th2 responses. Furthermore, elevated levels of the soluble form of CD30 (sCD30) in blood as well as of the expression of CD30 on the plasma membrane of T cells are associated with atopic disease.Objective To assess the potential usefulness of sCD30 levels as a prognostic indicator of and/or diagnostic marker for the development of atopic disease in children.Methods sCD30 levels in cord blood and peripheral blood from 36 2-year-old (10 atopic and 26 non-atopic) and 74 7-year-old (35 atopic and 39 non-atopic) children were determined employing an ELISA procedure. Atopy was diagnosed on the basis of clinical evaluation in combination with a positive skin prick test.Results No significant correlation between sCD30 levels in cord blood and the development of atopic disease at 2 or 7 years of age was observed. At 7 years of age, the circulating sCD30 levels in children with atopic disease (median 41 U/mL, range 6–503 U/mL) did not differ from the corresponding values for non-atopic subjects (median 41 U/mL, range 8–402 U/mL). The same was true for children at 2 years of age. Furthermore, the sCD30 levels of children who had developed atopic eczema/dermatitis syndrome by the age of 7 years (median 49 U/mL, range 14–503 U/mL) were not significantly elevated in comparison with those of the non-atopic children. Finally, neither sCD30 levels in cord blood nor peripheral blood at 2 or 7 years of age could be linked to a family history of atopy.Conclusion These findings indicate that the sCD30 concentration in cord blood is not a reliable prognostic indicator of, nor a useful diagnostic marker for, atopic disease in children up to 7 years of age. If such correlations do exist, they might be masked by age-dependent variations in the circulating levels of sCD30, which may reflect individual differences in the maturation of children's immunological responses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2222.2003.01792.x
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  • 10
    Electronic Resource
    Electronic Resource
    Basaloid squamous cell carcinoma of the palate (1994)
    Oxford, UK : Blackwell Publishing Ltd
    Histopathology 25 (1994), S. 0 
    Details
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2559.1994.tb01576.x
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