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51.
Bruna Los Marco Preußner Kathrin Eschke Ricardo Martin Vidal Azza Abdelgawad Didrik Olofsson Sandra Keiper Margarida Paulo-Pedro Alica Grindel Stefan Meinke Jakob Trimpert Florian Heyd 《Nucleic acids research》2022,50(12):6769
Antiviral innate immunity represents the first defense against invading viruses and is key to control viral infections, including SARS-CoV-2. Body temperature is an omnipresent variable but was neglected when addressing host defense mechanisms and susceptibility to SARS-CoV-2 infection. Here, we show that increasing temperature in a 1.5°C window, between 36.5 and 38°C, strongly increases the expression of genes in two branches of antiviral immunity, nitric oxide production and type I interferon response. We show that alternative splicing coupled to nonsense-mediated decay decreases STAT2 expression in colder conditions and suggest that increased STAT2 expression at elevated temperature induces the expression of diverse antiviral genes and SARS-CoV-2 restriction factors. This cascade is activated in a remarkably narrow temperature range below febrile temperature, which reflects individual, circadian and age-dependent variation. We suggest that decreased body temperature with aging contributes to reduced expression of antiviral genes in older individuals. Using cell culture and in vivo models, we show that higher body temperature correlates with reduced SARS-CoV-2 replication, which may affect the different vulnerability of children versus seniors toward severe SARS-CoV-2 infection. Altogether, our data connect body temperature and pre-mRNA processing to provide new mechanistic insight into the regulation of antiviral innate immunity. 相似文献
52.
Igor O. Fritsky Jolanta ?wi?tek-Koz?owska Agnieszka Dobosz Nikolay M. Dudarenko 《Inorganica chimica acta》2004,357(12):3746-3752
The formation of the molecular assemblies consisting of anionic and cationic molecules may lead to their interesting structural properties. In this work, we present three new structures based on the tetradentate oxime and amide open-chain ligand CH3-C(NOH)-C(O)-NH-(CH2)3-NH-C(O)-C(NOH)-CH3 (PAP). All the structures contain the complex cations, complex anions [M(PAP-3H)]− and solvating water molecules. These are H-bonded complex anions: [Ni(1,3-pn)2(H2O)2][Ni(PAP-3H)]2 · 4 H2O (1), [Ni(Im)4(H2O)2][Ni(PAP-3H)]2 (2) and [Cu(Im)4(H2O)2][Cu(PAP-3H)]2 · 2H2O (3) (Im=imidazole; 1-3-pn=1,3-diaminopropane). All compounds were synthesised by co-crystallisation of octahedral amine-containing cationic complex with oxime-containing anionic complexes in methanol solution. They were compared with some earlier reported assemblies based on the same ligand (PAP). The comparison of the structures reveals one distinct difference in the separation between the cis-situated oximate oxygen atoms O(1)?O(4) in the copper complexes. The consequence of this effect is the lengthening of the Cu-N distances. In the nickel complexes containing [Ni(PAP-3H)]− anion this effect is much less pronounced. 相似文献
53.
Kim TS Hague AB Lee TI Lian B Tegley CM Wang X Burgess TL Qian YX Ross S Tagari P Lin CH Mayeda C Dao J Jordan S Mohr C Cheetham J Viswanadhan V Tasker AS 《Bioorganic & medicinal chemistry letters》2004,14(1):87-90
A series of (4-piperidinylphenyl)aminoethyl amides based on dipeptide anilines were synthesized and tested against cathepsin K, cathepsin L and cathepsin B. These new non-covalent inhibitors exhibited single-digit nM inhibition of the cysteine proteases. Compounds 3 and 7 demonstrated potency in both mouse and human osteoclast resorption assays. 相似文献
54.
Christian Berger Sandra Berndt Annelie Pichert Stephan Theisgen Daniel Huster 《Biotechnology and bioengineering》2013,110(6):1681-1690
A protocol for the efficient isotopic labeling of large G protein‐coupled receptors with tryptophan in Escherichia coli as expression host was developed that sufficiently suppressed the naturally occurring L‐tryptophan indole lyase, which cleaves tryptophan into indole, pyruvate, and ammonia resulting in scrambling of the isotopic label in the protein. Indole produced by the tryptophanase is naturally used as messenger for cell–cell communication. Detailed analysis of different process conducts led to the optimal expression strategy, which mimicked cell–cell communication by the addition of indole during expression. Discrete concentrations of indole and 15N2‐L‐tryptophan at dedicated time points in the fermentation drastically increased the isotopic labeling efficiency. Isotope scrambling was only observed in glutamine, asparagine, and arginine side chains but not in the backbone. This strategy allows producing specifically tryptophan labeled membrane proteins at high concentrations avoiding the disadvantages of the often low yields of auxotrophic E. coli strains. In the fermentation process carried out according to this protocol, we produced ~15 mg of tryptophan labeled neuropeptide Y receptor type 2 per liter medium. Biotechnol. Bioeng. 2013; 110: 1681–1690. © 2013 Wiley Periodicals, Inc. 相似文献
55.
Sandra J. Walde Jan P. Nyrop J. Michael Hardman 《Experimental & applied acarology》1992,14(3-4):261-291
We addressed the question of persistence of predator and prey in a biological control system by examining temporal patterns ofPanonychus ulmi (Koch) and its predator,Typhlodromus pyri Scheuten at two geographic locations and at two spatial scales. At the scale of an orchard, bothP. ulmi andT. pyri were persistent over the time frame of 6 years. At the scale of an individual tree,T. pyri appeared to be more persistent than its prey,P. ulmi. We used a simulation model of single populations ofP. ulmi andT. pyri to determine which of several aspects of the biology of the two species could contribute to such a pattern. Spatial incongruity between predator and prey was essential for persistence of both species. The generalist food habit ofT. pyri probably contributes to the persistence ofT. pyri on individual trees, and may cause occasional extinction ofP. ulmi at this spatial scale. The presence of alternate food is likely an essential element for successful biological control in this system. Cannibalism byT. pyri results in higher prey densities, that is, it is detrimental to the biological control ofP. ulmi, but has no effect on the relative persistence of the two species. 相似文献
56.
Dejanira da Costa Lauria Elaine R. R. Rochedo Maria Luisa D. P. Godoy Eliane E. Santos Sandra S. Hacon 《Radiation and environmental biophysics》2012,51(4):367-374
This paper focuses on a survey of uranium and thorium decay chain radionuclides in food and drinking water from the thorium-rich (monazite-bearing) region of Buena, which is located in the state of Rio de Janeiro, Brazil. The radionuclide concentration values in the food and drinking water from Buena reached values higher than 100-fold the international reference values. The daily intake of radionuclides by the local population is similar to that of another high background radiation area in Brazil, but the intake is higher than that of residents from a normal background radiation area. Approximately 58?% of the food consumed by Buena inhabitants is produced locally. Based on that figure, locally produced food and the dilution of total radionuclides in the diet of residents caused by food importation are both highly relevant to a population’s intake of radionuclides. The concentration values for 210Pb and the radium isotopes in drinking water from Buena are among the highest values to be reported in the literature. 228Ra is the most important radionuclide ingested with both food and water among the inhabitants of Buena. 相似文献
57.
Mark S. Tichenor John M. Keith William M. Jones Joan M. Pierce Jeff Merit Natalie Hawryluk Mark Seierstad James A. Palmer Michael Webb Mark J. Karbarz Sandy J. Wilson Michelle L. Wennerholm Filip Woestenborghs Dominiek Beerens Lin Luo Sean M. Brown Marlies De Boeck Sandra R. Chaplan J. Guy Breitenbucher 《Bioorganic & medicinal chemistry letters》2012,22(24):7357-7362
The structure–activity relationships for a series of heteroaryl urea inhibitors of fatty acid amide hydrolase (FAAH) are described. Members of this class of inhibitors have been shown to inactivate FAAH by covalent modification of an active site serine with subsequent release of an aromatic amine from the urea electrophile. Systematic Ames II testing guided the optimization of urea substituents by defining the structure–mutagenicity relationships for the released aromatic amine metabolites. Potent FAAH inhibitors were identified having heteroaryl amine leaving groups that were non-mutagenic in the Ames II assay. 相似文献
58.
59.
Constance Dubuc Sandra Winters William L. Allen Lauren J. N. Brent Julie Cascio Dario Maestripieri Angelina V. Ruiz-Lambides Anja Widdig James P. Higham 《Proceedings. Biological sciences / The Royal Society》2014,281(1794)
Sexual selection promotes the prevalence of heritable traits that increase an individual''s reproductive rate. Despite theoretically strong directional selection, sexually selected traits can show inter-individual variation. Here, we investigate whether red skin ornamentation, a rare example of a male mammalian trait involved in mate attraction, influences fecundity and is heritable in rhesus macaques (Macaca mulatta), and explore the mechanisms that are involved in maintaining trait variation. Interestingly, the trait is expressed by and is attractive to both sexes. We collected facial images of 266 free-ranging individuals and modelled skin redness and darkness to rhesus macaque vision. We used 20 years of genetic parentage data to calculate selection gradients on the trait and perform heritability analyses. Results show that males who were both darkly coloured and high-ranking enjoyed higher fecundity. Female skin redness was positively linked to fecundity, although it remains unclear whether this influences male selectiveness. Heritability explained 10–15% of the variation in redness and darkness, and up to 30% for skin darkness when sexes are considered separately, suggesting sex-influenced inheritance. Our results suggest that inter-individual variation is maintained through condition-dependence, with an added effect of balancing selection on male skin darkness, providing rare evidence for a mammalian trait selected through inter-sexual selection. 相似文献
60.