| 1. |
- Gruden, Marina A., et al.
(författare)
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Correlation between Protective Immunity to alpha-Synuclein Aggregates, Oxidative Stress and Inflammation
- 2012
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Ingår i: Neuroimmunomodulation. - : S. Karger AG. - 1021-7401 .- 1423-0216. ; 19:6, s. 334-342
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Protein aggregation leading to central amyloid deposition is implicated in Parkinson's disease (PD). During disease progression, inflammation and oxidative stress may well invoke humoral immunity against pathological aggregates of PD-associated alpha-synuclein. The aim was to investigate any possible concurrence between autoimnnune responses to alpha-synuclein monomers, oligomers or fibrils with oxidative stress and inflammation.Methods: The formation of alpha-synuclein amyloid species was assessed by thioflavin-T assay and atomic force microscopy was employed to confirm their morphology. Serum autoantibody titers to alpha-synuclein conformations were determined by ELISA. Enzyme activity and concentrations of oxidative stress/inflammatory indicators were evaluated by enzyme and ELISA protocols.Results: In PD patient sera, a differential increase in autoantibody titers to alpha-synuclein monomers, toxic oligomers or fibrils was associated with boosted levels of the pro-inflammatory cytokine interleukin-6 and tumour necrosis factor-alpha, but a decrease in interferon-gamma concentration. In addition, levels of malondialdehyde were elevated whilst those of glutathione were reduced along with decrements in the activity of the antioxidants: superoxide dismutase, catalase and glutathione transferase.Conclusions: It is hypothesized that the generation of alpha-synuclein amyloid aggregates allied with oxidative stress and inflammatory reactions may invoke humoral immunity protecting against dopaminergic neuronal death. Hence, humoral immunity is a common integrative factor throughout PD progression which is directed towards prevention of further neurodegeneration, so potential treatment strategies should attempt to maintain PD patient immune status. Copyright (c) 2012 S. Karger AG, Basel
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| 2. |
- Gruden, Marina A., et al.
(författare)
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Immunoprotection against toxic biomarkers is retained during Parkinson's disease progression
- 2011
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Ingår i: Journal of Neuroimmunology. - : Elsevier. - 0165-5728 .- 1872-8421. ; 233:1-2, s. 221-227
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to ascertain any possible linkage between humoral immune responses to principal biomarkers (α-synuclein monomers, its toxic oligomers or fibrils, dopamine and S100B) and cellular immunity in Parkinson's disease development. There were elevated autoantibody titers to α-synuclein monomers, oligomers plus fibrils in 72%, 56%, and 17% of Parkinsonian patients respectively with a 5-year disease duration. Additionally, there were increased titers to dopamine and S100B (96% and 89%) in the 5-year patient group. All of these values subsided in 10-year sufferers. Furthermore, CD3+, CD4+, CD8+ T-lymphocyte and B-lymphocyte subsets declined in the patient cohort during Parkinsonism indicating disease associated reductions in these lymphocyte subsets.
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| 3. |
- Morozova, Tatiana I, et al.
(författare)
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Structural and Dynamical Properties of Elastin-Like Peptides near Their Lower Critical Solution Temperature.
- 2023
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 24:4, s. 1912-1923
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Tidskriftsartikel (refereegranskat)abstract
- Elastin-like peptides (ELPs) are artificially derived intrinsically disordered proteins (IDPs) mimicking the hydrophobic repeat unit in the protein elastin. ELPs are characterized by a lower critical solution temperature (LCST) in aqueous media. Here, we investigate the sequence GVG(VPGVG)3 over a wide range of temperatures (below, around, and above the LCST) and peptide concentrations employing all-atom molecular dynamics simulations, where we focus on the role of intra- and interpeptide interactions. We begin by investigating the structural properties of a single peptide that demonstrates a hydrophobic collapse with temperature, albeit moderate, because the sequence length is short. We observe a change in the interaction between two peptides from repulsive to attractive with temperature by evaluating the potential of mean force, indicating an LCST-like behavior. Next, we explore dynamical and structural properties of peptides in multichain systems. We report the formation of dynamical aggregates with coil-like conformation, in which valine central residues play an important role. Moreover, the lifetime of contacts between chains strongly depends on the temperature and can be described by a power-law decay that is consistent with the LCST-like behavior. Finally, the peptide translational and internal motion are slowed by an increase in the peptide concentration and temperature.
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| 4. |
- Noordeloos, Machiel Evert, et al.
(författare)
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Three new Entoloma species of the Cyanula clade from (sub)alpine habitats in Northern Norway and Sweden
- 2021
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Ingår i: Sydowia. - 0082-0598. ; 73, s. 185-196
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Tidskriftsartikel (refereegranskat)abstract
- Three Entoloma species belonging to the Cyanula clade from (middle-) northern boreal and alpine areas are described as new to science. Entoloma montanum, E. nordlandicum, and E. septentrionale, recorded from the Holmvassdalen area at Grane, North- ern Norway while E. montanum shows a wide distribution in Northern Scandinavia and the Caucasus. Entoloma nordlandicum, however, has recently been recorded also from the Netherlands. The three species are phylogenetically well defined based on analysis of the nrDNA ITS region and they are distant from their closest relatives. Morphological descriptions of each species are given, as well as their ecology, distribution and relationships towards similar species are discussed.
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| 5. |
- Otrokhov, Grigory, et al.
(författare)
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Enzymatic synthesis of polyaniline/multi-walled carbon nanotube composite with core shell structure and its electrochemical characterization for supercapacitor application
- 2014
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Ingår i: Electrochimica Acta. - : Elsevier. - 0013-4686 .- 1873-3859. ; 123, s. 151-157
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Tidskriftsartikel (refereegranskat)abstract
- A new method involving laccase-mediator system has been developed for environmentally friendly synthesis of polyaniline/multi-walled carbon nanotubes (PANI/MWCNT) composite. Fungal laccase, potassium octocyanomolibdate (4+) and atmospheric oxygen served as catalyst, redox-mediator and terminal oxidant, respectively. The structure, morphology and electrical conductivity of composites with different PANI content were investigated. The energy storage of enzymatically obtained composite consists of an electrical double layer capacitance as well as pseudocapacitance of conducting polymer. The obtained PANI/MWCNT composite with PANI content ca. 49 wt.% had high specific capacitance and cycle stability during doping/dedoping. The specific capacitance of this composite measured by cyclic voltammetry technique with potential scan rate of 5 mV/s was ca. 440 F/g. The specific capacitance of the composite decreased by less than 7% of its maximum value after 1000 scan cycles between -0.1 and 0.7 V. Supercapacitor (SC) shell was made from flexible adhesive tape (regular Scotch tape) and current collector was formed after its separation from the surface of graphite foil. The ethanol dispersion of PANI/MWCNT composite was deposited on the current collector surface. The gel polymer electrolyte (polyvinyl alcohol in 1 M phosphoric acid) was employed as both electrolyte medium and separator. The energy and power densities under an operating window of 0.7 V were ca. 7.03 Wh/kg and 5.2 kW/kg, respectively. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.
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| 6. |
- Pankratov, Dmitry, et al.
(författare)
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A comparative study of biocathodes based on multiwall carbon nanotube buckypapers modified with three different multicopper oxidases
- 2013
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Ingår i: Electroanalysis. - : Wiley-VCH Verlagsgesellschaft. - 1040-0397 .- 1521-4109. ; 25:5, s. 1143-1149
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Tidskriftsartikel (refereegranskat)abstract
- 14 Single- and multi-walled carbon nanotubes from different sources were characterized in detail, and the characteristics obtained were carefully analyzed. The carbon material with the highest capacitance, and also other superior properties ("Taunit-M" from "NanoTechCenter", Russia), was chosen for further modification and fabrication of buckypaper based electrodes. These electrodes were biomodified with plant and fungal laccases, as well as fungal bilirubin oxidase. The designed biocathodes were studied in simple buffers and also in a complex physiol. fluid (human serum). Biocathodes based on immobilized fungal laccase were bioelectrocatalytically inactive in chloride contg. media at neutral pH. In spite of the quite high current densities realized using biodevices based on plant laccase and fungal bilirubin oxidase, the limited thermal stability of the enzymes renders the biocathodes inadequate for practical applications in implanted situations.
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| 7. |
- Shleev, Sergey, et al.
(författare)
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Stable floating air diffusion biocathode based on direct electron transfer reactions between carbon particles and high redox potential laccase
- 2010
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Ingår i: Fuel Cells. - : Wiley-VCH Verlag GmbH & Co. KGaA. - 1615-6846 .- 1615-6854. ; 10:4, s. 726-733
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Tidskriftsartikel (refereegranskat)abstract
- We report on the assembly and characterisation of a high potential, stable, mediator-less and cofactor free biocathode based on a fungal laccase (Lc), adsorbed on highly dispersed carbonaceous materials. First, the stability and activity of Trametes hirsuta Lc immobilised on different carbon particles were studied and compared to the solubilised enzyme. Based on the experimental results and a literature analysis, the carbonaceous material BM-4 was chosen to design efficient and stable biocatalysts for the production of a ‘floating’ air diffusion Lc-based biocathode. Voltammetric characteristics and operational stability of the biocathode were investigated. The current density of oxygen reduction at the motionless biocathode in a quiet, air saturated citrate buffer (100 mM, pH 4.5, 23 °C) reached values as high as 0.3 mA cm–2 already at 0.7 V versus NHE. The operational stability of the biocathode depended on the current density of the device. For example, at low current density (20 lA cm–2), the biocathode lost only 5× of its initial power after 1 month of continuous operation. However, when the device was polarised at 150 mV it lost more than 32× of its initial power in just 10 min. We also found that co-immobilisation of Lc and peroxidase on highly dispersed carbon materials could protect the biocatalyst from rapid inactivation by hydrogen peroxide produced during electrocatalytic reactions at high-current densities.
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| 8. |
- Zamora, Juan Carlos, et al.
(författare)
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Considerations and consequences of allowing DNA sequence data as types of fungal taxa
- 2018
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Ingår i: IMA Fungus. - : INT MYCOLOGICAL ASSOC. - 2210-6340 .- 2210-6359. ; 9:1, s. 167-185
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Tidskriftsartikel (refereegranskat)abstract
- Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.
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