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Jason L. Pugh Sarah A. Foster Alona S. Sukhina Janka Petravic Jennifer L. Uhrlaub Jose Padilla‐Torres Tomonori Hayashi Kei Nakachi Megan J. Smithey Janko Nikolich‐Žugich 《Aging cell》2016,15(4):686-693
Aging‐related decline in immunity is believed to be the main driver behind decreased vaccine efficacy and reduced resistance to infections in older adults. Unrepaired DNA damage is known to precipitate cellular senescence, which was hypothesized to be the underlying cause of certain age‐related phenotypes. Consistent with this, some hallmarks of immune aging were more prevalent in individuals exposed to whole‐body irradiation (WBI), which leaves no anatomical repository of undamaged hematopoietic cells. To decisively test whether and to what extent WBI in youth will leave a mark on the immune system as it ages, we exposed young male C57BL/6 mice to sublethal WBI (0.5–4 Gy), mimicking human survivor exposure during nuclear catastrophe. We followed lymphocyte homeostasis thorough the lifespan, response to vaccination, and ability to resist lethal viral challenge in the old age. None of the irradiated groups showed significant differences compared with mock‐irradiated (0 Gy) animals for the parameters measured. Even the mice that received the highest dose of sublethal WBI in youth (4 Gy) exhibited equilibrated lymphocyte homeostasis, robust T‐ and B‐cell responses to live attenuated West Nile virus (WNV) vaccine and full survival following vaccination upon lethal WNV challenge. Therefore, a single dose of nonlethal WBI in youth, resulting in widespread DNA damage and repopulation stress in hematopoietic cells, leaves no significant trace of increased immune aging in a lethal vaccine challenge model. 相似文献
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Jens?Nielsen John?Archer Magbubah?Essack Vladimir?B.?Bajic Takashi?Gojobori Ivan?MijakovicEmail authorView authors OrcID profile 《Applied microbiology and biotechnology》2017,101(12):4837-4851
The incentive for developing microbial cell factories for production of fuels and chemicals comes from the ability of microbes to deliver these valuable compounds at a reduced cost and with a smaller environmental impact compared to the analogous chemical synthesis. Another crucial advantage of microbes is their great biological diversity, which offers a much larger “catalog” of molecules than the one obtainable by chemical synthesis. Adaptation to different environments is one of the important drives behind microbial diversity. We argue that the Red Sea, which is a rather unique marine niche, represents a remarkable source of biodiversity that can be geared towards economical and sustainable bioproduction processes in the local area and can be competitive in the international bio-based economy. Recent bioprospecting studies, conducted by the King Abdullah University of Science and Technology, have established important leads on the Red Sea biological potential, with newly isolated strains of Bacilli and Cyanobacteria. We argue that these two groups of local organisms are currently most promising in terms of developing cell factories, due to their ability to operate in saline conditions, thus reducing the cost of desalination and sterilization. The ability of Cyanobacteria to perform photosynthesis can be fully exploited in this particular environment with one of the highest levels of irradiation on the planet. We highlight the importance of new experimental and in silico methodologies needed to overcome the hurdles of developing efficient cell factories from the Red Sea isolates. 相似文献
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Kateřina Sukačová Radka Kočí Milena Žídková Tomáš Vítěz Martin Trtílek 《International journal of phytoremediation》2017,19(10):909-914
Eutrophication of water by nutrient pollution remains an important environmental issue. The aim of this study was to evaluate the nutrient uptake capacity of an algal biofilm as a means to treat polluted water. In addition, the study investigated the nutrient removal process. The algal biofilm was able to remove 99% of phosphorus within 24 hours of P addition, with the PO4-P concentration in inflowing water ranging from 3 to 10 mg L?1. Different patterns of phosphorus and nitrogen removal were observed. Daily quantity of removed NO3-N ranged from 2 to 25% and was highly dependent on solar irradiance. Precipitation of phosphorus during the removal process was studied using X-ray diffraction analyses and was not confirmed in the biofilm. The biofilm system we constructed has a high efficiency for phosphorus removal and, therefore, has great potential for integration into wastewater treatment processes. 相似文献
337.
Clive T. Darwell Daniel SoutoVilars Jan Michalek Sotiria Boutsi Brus Isua Mentap Sisol Thomas Kuyaiva George Weiblen Vlastimil Kivan Vojtech Novotny Simon T. Segar 《Ecology and evolution》2022,12(4)
Reproductive isolation in response to divergent selection is often mediated via third‐party interactions. Under these conditions, speciation is inextricably linked to ecological context. We present a novel framework for understanding arthropod speciation as mediated by Wolbachia, a microbial endosymbiont capable of causing host cytoplasmic incompatibility (CI). We predict that sympatric host sister‐species harbor paraphyletic Wolbachia strains that provide CI, while well‐defined congeners in ecological contact and recently diverged noninteracting congeners are uninfected due to Wolbachia redundancy. We argue that Wolbachia provides an adaptive advantage when coupled with reduced hybrid fitness, facilitating assortative mating between co‐occurring divergent phenotypes—the contact contingency hypothesis. To test this, we applied a predictive algorithm to empirical pollinating fig wasp data, achieving up to 91.60% accuracy. We further postulate that observed temporal decay of Wolbachia incidence results from adaptive host purging—adaptive decay hypothesis—but implementation failed to predict systematic patterns. We then account for post‐zygotic offspring mortality during CI mating, modeling fitness clines across developmental resources—the fecundity trade‐off hypothesis. This model regularly favored CI despite fecundity losses. We demonstrate that a rules‐based algorithm accurately predicts Wolbachia infection status. This has implications among other systems where closely related sympatric species encounter adaptive disadvantage through hybridization. 相似文献
338.
Pavel Macek Lukáš Žídek Michaela Rumlová Iva Pichová Vladimír Sklenář 《Biomolecular NMR assignments》2008,2(1):43-45
Mason-Pfizer monkey virus (M-PMV) belongs to the family of betaretroviruses characterized by the assembly of immature particles
within cytoplasm of infected cells in contrast to other retroviruses (e.g. HIV, RSV) that assemble their immature particles
at a plasma membrane. Simultaneously with or shortly after budding a virus-encoded protease is activated and the Gag polyprotein
is cleaved into three major structural proteins: matrix (MA), capsid (CA), and nucleocapsid (NC) protein. Mature retroviral
CA proteins consist of two independently folded structural domains: N-terminal domain (NTD) and C-terminal dimerization domain
(CTD), separated by a flexible linker. As a first step toward the solution structure elucidation, we present nearly complete
backbone and side-chain 1H, 15N and 13C resonance assignment of the M-PMV NTD CA. 相似文献
339.
Malkov SN Zivković MV Beljanski MV Hall MB Zarić SD 《Journal of molecular modeling》2008,14(8):769-775
The correlation between the primary and secondary structures of proteins was analysed using a large data set from the Protein
Data Bank. Clear preferences of amino acids towards certain secondary structures classify amino acids into four groups: α-helix
preferrers, strand preferrers, turn and bend preferrers, and His and Cys (the latter two amino acids show no clear preference
for any secondary structure). Amino acids in the same group have similar structural characteristics at their Cβ and Cγ atoms
that predicts their preference for a particular secondary structure. All α-helix preferrers have neither polar heteroatoms
on Cβ and Cγ atoms, nor branching or aromatic group on the Cβ atom. All strand preferrers have aromatic groups or branching
groups on the Cβ atom. All turn and bend preferrers have a polar heteroatom on the Cβ or Cγ atoms or do not have a Cβ atom
at all. These new rules could be helpful in making predictions about non-natural amino acids.
相似文献
Snežana D. ZarićEmail: |
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