| 1. |
- Artaxo, Paulo, et al.
(author)
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Tropical and Boreal Forest – Atmosphere Interactions : A Review
- 2022
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In: Tellus. Series B, Chemical and physical meteorology. - : Stockholm University Press. - 0280-6509 .- 1600-0889. ; 74:1, s. 24-163
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Research review (peer-reviewed)abstract
- This review presents how the boreal and the tropical forests affect the atmosphere, its chemical composition, its function, and further how that affects the climate and, in return, the ecosystems through feedback processes. Observations from key tower sites standing out due to their long-term comprehensive observations: The Amazon Tall Tower Observatory in Central Amazonia, the Zotino Tall Tower Observatory in Siberia, and the Station to Measure Ecosystem-Atmosphere Relations at Hyytiäla in Finland. The review is complemented by short-term observations from networks and large experiments.The review discusses atmospheric chemistry observations, aerosol formation and processing, physiochemical aerosol, and cloud condensation nuclei properties and finds surprising similarities and important differences in the two ecosystems. The aerosol concentrations and chemistry are similar, particularly concerning the main chemical components, both dominated by an organic fraction, while the boreal ecosystem has generally higher concentrations of inorganics, due to higher influence of long-range transported air pollution. The emissions of biogenic volatile organic compounds are dominated by isoprene and monoterpene in the tropical and boreal regions, respectively, being the main precursors of the organic aerosol fraction.Observations and modeling studies show that climate change and deforestation affect the ecosystems such that the carbon and hydrological cycles in Amazonia are changing to carbon neutrality and affect precipitation downwind. In Africa, the tropical forests are so far maintaining their carbon sink.It is urgent to better understand the interaction between these major ecosystems, the atmosphere, and climate, which calls for more observation sites, providing long-term data on water, carbon, and other biogeochemical cycles. This is essential in finding a sustainable balance between forest preservation and reforestation versus a potential increase in food production and biofuels, which are critical in maintaining ecosystem services and global climate stability. Reducing global warming and deforestation is vital for tropical forests.
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| 2. |
- Maier, A., et al.
(author)
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Transgenic introduction of a glycolate oxidative cycle into A. thaliana chloroplasts leads to growth improvement
- 2012
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In: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 3:FEB
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Journal article (peer-reviewed)abstract
- The photorespiratory pathway helps illuminated C3-plants under conditions of limited CO2availability by effectively exporting reducing equivalents in form of glycolate out of the chloroplast and regenerating glycerate-3-P as substrate for RubisCO. On the other hand, this pathway is considered as probably futile because previously assimilated CO2 is released in mitochondria. Consequently, a lot of effort has been made to reduce this CO2 loss either by reducing fluxes via engineering RubisCO or circumventing mitochondrial CO2 release by the introduction of new enzyme activities. Here we present an approach following the latter route, introducing a complete glycolate catabolic cycle in chloroplasts ofArabidopsis thalianacomprising glycolate oxidase (GO), malate synthase (MS), and catalase (CAT). Results from plants bearing both GO and MS activities have already been reported. This previous work showed that the H2O2produced by GO had strongly negative effects. These effects can be prevented by introducing a plastidial catalase activity, as reported here. Transgenic lines bearing all three transgenic enzyme activities were identified and some with higher CAT activity showed higher dry weight, higher photosynthetic rates, and changes in glycine/serine ratio compared to the wild type. This indicates that the fine-tuning of transgenic enzyme activities in the chloroplasts seems crucial and strongly suggests that the approach is valid and that it is possible to improve the growth of A. thaliana by introducing a synthetic glycolate oxidative cycle into chloroplasts.
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| 3. |
- Wagner, I, et al.
(author)
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Preliminary evaluation of cytosine-phosphate-guanine oligodeoxynucleotides bound to gelatine nanoparticles as immunotherapy for canine atopic dermatitis.
- 2017
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In: The Veterinary Record. - : Wiley. - 0042-4900 .- 2042-7670. ; 181:5
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Journal article (peer-reviewed)abstract
- Cytosine-phosphate-guanine oligodeoxynucleotides (CpG ODN) are a promising new immunotherapeutic treatment option for canine atopic dermatitis (AD). The aim of this uncontrolled pilot study was to evaluate clinical and immunological effects of gelatine nanoparticle (GNP)-bound CpG ODN (CpG GNP) on atopic dogs. Eighteen dogs with AD were treated for 8 weeks (group 1, n=8) or 18 weeks (group 2, n=10). Before inclusion and after 2 weeks, 4 weeks, 6 weeks (group 1+2), 8 weeks, 12 weeks and 16 weeks (group 2) 75 µg CpG ODN/dog (bound to 1.5 mg GNP) were injected subcutaneously. Pruritus was evaluated daily by the owner. Lesions were evaluated and serum concentrations and mRNA expressions of interferon-γ, tumour necrosis factor-α, transforming growth factor-β, interleukin (IL) 10 and IL-4 (only mRNA expression) were determined at inclusion and after 8 weeks (group 1+2) and 18 weeks (group 2). Lesions and pruritus improved significantly from baseline to week 8. Mean improvements from baseline to week 18 were 23 per cent and 44 per cent for lesions and pruritus, respectively, an improvement of ≥50 per cent was seen in six out of nine and three out of six dogs, respectively. IL-4 mRNA expression decreased significantly. The results of this study show a clinical improvement of canine AD with CpG GNP comparable to allergen immunotherapy. Controlled studies are needed to confirm these findings.
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