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101.
Massimo Maddaloni Irina Kochetkova SangMu Jun Gayle Callis Theresa Thornburg David W. Pascual 《PloS one》2015,10(1)
Autoimmune diseases arise from the loss of tolerance to self, and because the etiologies of such diseases are largely unknown, symptomatic treatments rely on anti-inflammatory and analgesic agents. Tolerogenic treatments that can reverse disease are preferred, but again, often thwarted by not knowing the responsible auto-antigens (auto-Ags). Hence, a viable alternative to stimulating regulatory T cells (Tregs) is to induce bystander tolerance. Colonization factor antigen I (CFA/I) has been shown to evoke bystander immunity and to hasten Ag-specific Treg development independent of auto-Ag. To translate in treating human autoimmune diseases, the food-based Lactococcus was engineered to express CFA/I fimbriae, and Lactococcus-CFA/I fermented milk fed to arthritic mice proved highly efficacious. Protection occurred via CD39+ Tregs producing TGF-β and IL-10 to potently suppress TNF-α production and neutrophil influx into the joints. Thus, these data demonstrate the feasibility of oral nutraceuticals for treating arthritis, and potency of protection against arthritis was improved relative to that obtained with Salmonella-CFA/I. 相似文献
102.
Boris R. Krasnov Georgy S. Shenbrot Luther van der Mescht Elizabeth M. Warburton Irina S. Khokhlova 《Ecography》2019,42(5):1000-1011
We studied patterns of phylogenetic and compositional diversity of fleas parasitic on small mammals and asked whether these patterns are affected by environmental variation or evolutionary/historical processes. We considered environmental variation via both off‐host (air temperature, precipitation, the amount of green vegetation, latitude) and host‐associated (phylogenetic and species composition) environments. The indicators of evolutionary/historical processes were phylogenetic and compositional uniqueness estimated via phylogenetic or compositional, respectively, β‐diversity of either fleas or hosts. We found that phylogenetic uniqueness of flea assemblages was the main predictor of their phylogenetic diversity in all realms. In addition, host phylogenetic diversity and uniqueness played also some role in the Palearctic, whereas the effect of the off‐host environment was either extremely weak or absent. Compositional diversity of fleas was consistently affected by compositional diversity of hosts in all realms except the Neotropics. The effect of the off‐host environment on compositional flea diversity was substantial in all realms except the Palearctic. No effect of latitude on either metric of flea diversity was found. We conclude that phylogenetic diversity of fleas is driven mainly by evolutionary/historical processes, whereas drivers of their compositional diversity are associated with current ecological conditions. 相似文献
103.
104.
Carla D. Jorge Nuno Borges Irina Bagyan Andreas Bilstein Helena Santos 《Extremophiles : life under extreme conditions》2016,20(3):251-259
Protein misfolding, aggregation and deposition in the brain, in the form of amyloid, are implicated in the etiology of several neurodegenerative disorders, such as Alzheimer’s, Parkinson’s and prion diseases. Drugs available on the market reduce the symptoms, but they are not a cure. Therefore, it is urgent to identify promising targets and develop effective drugs. Preservation of protein native conformation and/or inhibition of protein aggregation seem pertinent targets for drug development. Several studies have shown that organic solutes, produced by extremophilic microorganisms in response to osmotic and/or heat stress, prevent denaturation and aggregation of model proteins. Among these stress solutes, mannosylglycerate, mannosylglyceramide, di-myo-inositol phosphate, diglycerol phosphate and ectoine are effective in preventing amyloid formation by Alzheimer’s Aβ peptide and/or α-synuclein in vitro. Moreover, mannosylglycerate is a potent inhibitor of Aβ and α-synuclein aggregation in living cells, and mannosylglyceramide and ectoine inhibit aggregation and reduce prion peptide-induced toxicity in human cells. This review focuses on the efficacy of stress solutes from hyper/thermophiles and ectoines to prevent amyloid formation in vitro and in vivo and their potential application in drug development against protein misfolding diseases. Current and envisaged applications of these extremolytes in neurodegenerative diseases and healthcare will also be addressed. 相似文献
105.
Shtyrlin Valery G. Borissenok Valery A. Serov Nikita Yu. Simakov Vladimir G. Bragunets Vyacheslav A. Trunin Ivan R. Tereshkina Irina A. Koshkin Sergey A. Bukharov Mikhail S. Gilyazetdinov Edward M. Shestakov Evgeny E. Sirotkina Anna G. Zakharov Alexey V. 《Origins of life and evolution of the biosphere》2019,49(1-2):1-18
Origins of Life and Evolution of Biospheres - Syntheses under shock in nitrogen bubbled samples of the water – formamide – bicarbonate – sodium hydroxide system at... 相似文献
106.
Igor Prudovsky Damien Carter Doreen Kacer Monica Palmeri Tee Soul Chloe Kumpel Kathleen Pyburn Karyn Barrett Victoria DeMambro Ilya Alexandrov Irina Brandina Robert Kramer Joseph Rappold 《Journal of cellular physiology》2019,234(11):19121-19129
Damage-associated molecular patterns, including mitochondrial DNA (mtDNA) are released during hemorrhage resulting in the development of endotheliopathy. Tranexamic acid (TXA), an antifibrinolytic drug used in hemorrhaging patients, enhances their survival despite the lack of a comprehensive understanding of its cellular mechanisms of action. The present study is aimed to elucidate these mechanisms, with a focus on mitochondria. We found that TXA inhibits the release of endogenous mtDNA from granulocytes and endothelial cells. Furthermore, TXA attenuates the loss of the endothelial monolayer integrity induced by exogenous mtDNA. Using the Seahorse XF technology, it was demonstrated that TXA strongly stimulates mitochondrial respiration. Studies using Mitotracker dye, cells derived from mito-QC mice, and the ActivSignal IPAD assay, indicate that TXA stimulates biogenesis of mitochondria and inhibits mitophagy. These findings open the potential for improvement of the strategies of TXA applications in trauma patients and the development of more efficient TXA derivatives. 相似文献
107.
Alexandra Denisova Aygul Halilova Vladimir Breus Irina Breus 《Soil & Sediment Contamination》2011,20(7):824-840
Biostimulation based on usage of soil amendments is growing due to their efficiency in removing different petroleum hydrocarbons (PHC) from contaminated sand or loam-sand soils. However, the research on clay-rich soils with higher organic carbon content, in which PHC biodegradation may proceed differently and which are more difficult to clean up, has been less extensive. In a pot experiment, we studied and compared the effects of two soil amendments, natural zeolite-containing material (ZCM, 50 g kg?1) as a bulking agent and ammonium nitrate (0.3 g N kg?1) as a nitrogen fertilizer, on biodegradation of n-tridecane (1 wt.%) in a weakly acidic heavy clay loam leached chernozem with fairly high organic carbon content (3.71%). After 48 days, the nitrogen-amended contaminated soil showed enhancement of both respiratory activity (basal and substrate-induced respiration rates) and the number of n-tridecane- degraders. As a consequence, the extent of n-tridecane biodegradation (86.5%) was essentially higher in the presence of added nitrogen than that in the non-amended soil (73.7%). In contrast, due to the partial retention of n-tridecane molecules in its pores, ZCM retarded biodegradation to 56.0%, showed no significant effect on the number of n-tridecane-degraders and, moreover, enhanced the decomposition of the soil intrinsic organic matter. The obtained data indicate that more precautions should be considered when using porous sorbents such as ZCM for remedial arrangements in PHC-contaminated soils. 相似文献
108.
Svitashev SK Pawlowski WP Makarevitch I Plank DW Somers DA 《The Plant journal : for cell and molecular biology》2002,32(4):433-445
To more fully characterize the internal structure of transgene loci and to gain further understanding of mechanisms of transgene locus formation, we sequenced more than 160 kb of complex transgene loci in two unrelated transgenic oat (Avena sativa L.) lines transformed using microprojectile bombardment. The transgene locus sequences from both lines exhibited extreme scrambling of non-contiguous transgene and genomic fragments recombined via illegitimate recombination. A perfect direct repeat of the delivered DNA, and inverted and imperfect direct repeats were detected in the same transgene locus indicating that homologous recombination and synthesis-dependent mechanism(s), respectively, were also involved in transgene locus rearrangement. The most unexpected result was the small size of the fragments of delivered and genomic DNA incorporated into the transgene loci via illegitimate recombination; 50 of the 82 delivered DNA fragments were shorter than 200 bp. Eleven transgene and genomic fragments were shorter than the DNA lengths required for Ku-mediated non-homologous end joining. Detection of these small fragments provided evidence that illegitimate recombination was most likely mediated by a synthesis-dependent strand-annealing mechanism that resulted in transgene scrambling. Taken together, these results indicate that transgene locus formation involves the concerted action of several DNA break-repair mechanisms. 相似文献
109.
Fredheim EG Granslo HN Flægstad T Figenschau Y Rohde H Sadovskaya I Mollnes TE Klingenberg C 《FEMS immunology and medical microbiology》2011,63(2):269-280
Staphylococcus epidermidis is a frequent cause of nosocomial infections. The central virulence factor of S. epidermidis is biofilm formation. Polysaccharide intercellular adhesin (PIA) constitutes the major biofilm matrix-component. PIA and biofilm have been implicated in S. epidermidis evasion of host immune defence. We examined the effects of S. epidermidis PIA on the inflammatory response with focus on complement activation. We used a human whole-blood ex vivo model of infection and compared the effects of a PIA-positive S. epidermidis strain (SE1457) and its PIA-negative isogenic mutant (M10). The independent effect of purified PIA on complement activation was investigated. In glucose-rich media, the mutant formed a proteinacious DNA-rich biofilm, whereas SE1457 formed a thick PIA-biofilm. In biofilm growth, SE1457 induced a stronger activation of the complement system compared with M10. We verified that purified PIA was independently responsible for a strong activation of the complement system. In contrast, M10 induced higher granulocyte activation by expression of CD11b and higher secretion of cytokines. We conclude that PIA has potent pro-inflammatory properties by activating the complement system. However, in a complex balance of the immune response, the decreased activation of granulocytes and cytokines by a PIA biofilm may limit host eradication of S. epidermidis. 相似文献
110.
George Calin Guglielmina N Ranzani Dino Amadori Vlad Herlea Irina Matei Giuseppe Barbanti-Brodano Massimo Negrini 《BMC genetics》2001,2(1):14-7