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https://www.readbyqxmd.com/read/28646336/nogo-a-antibodies-enhance-axonal-repair-and-remyelination-in-neuro-inflammatory-and-demyelinating-pathology
#1
Benjamin V Ineichen, Sandra Kapitza, Christiane Bleul, Nicolas Good, Patricia S Plattner, Maryam S Seyedsadr, Julia Kaiser, Marc P Schneider, Björn Zörner, Roland Martin, Michael Linnebank, Martin E Schwab
Two hallmarks of chronic multiple sclerosis lesions are the absence of significant spontaneous remyelination and primary as well as secondary neurodegeneration. Both characteristics may be influenced by the presence of inhibitory factors preventing myelin and neuronal repair. We investigated the potential of antibodies against Nogo-A, a well-known inhibitory protein for neuronal growth and plasticity, to enhance neuronal regeneration and remyelination in two animal models of multiple sclerosis. We induced a targeted experimental autoimmune encephalomyelitis (EAE) lesion in the dorsal funiculus of the cervical spinal cord of adult rats resulting in a large drop of skilled forelimb motor functions...
June 23, 2017: Acta Neuropathologica
https://www.readbyqxmd.com/read/28646326/transposable-elements-mediate-adaptive-debilitation-of-flagella-in-experimental-escherichia-coli-populations
#2
Gordon R Plague, Krystal S Boodram, Kevin M Dougherty, Sandar Bregg, Daniel P Gilbert, Hira Bakshi, Daniel Costa
Although insertion sequence (IS) elements are generally considered genomic parasites, they can mediate adaptive genetic changes in bacterial genomes. We discovered that among 12 laboratory-evolved Escherichia coli populations, three had experienced at least six different IS1-mediated deletions of flagellar genes. These deletions all involved the master flagellar regulator flhDC, and as such completely incapacitate motility. Two lines of evidence strongly suggest that these deletions were adaptive in our evolution experiment: (1) parallel evolution in three independent populations is highly unlikely just by chance, and (2) one of these deletion mutations swept to fixation within ~1000 generations, which is over two million times faster than expected if this deletion was instead selectively neutral and thus evolving by genetic drift...
June 23, 2017: Journal of Molecular Evolution
https://www.readbyqxmd.com/read/28645195/mutational-biases-influence-parallel-adaptation
#3
Arlin Stoltzfus, David M McCandlish
While mutational biases strongly influence neutral molecular evolution, the role of mutational biases in shaping the course of adaptation is less clear. Here we consider the frequency of transitions relative to transversions among adaptive substitutions. Because mutation rates for transitions are higher than those for transversions, if mutational biases influence the dynamics of adaptation, then transitions should be over-represented among documented adaptive substitutions. To test this hypothesis, we assembled 2 sets of data on putatively adaptive amino acid replacements that have occurred in parallel during evolution, either in nature or in the laboratory...
June 22, 2017: Molecular Biology and Evolution
https://www.readbyqxmd.com/read/28644493/photoelectrochemical-devices-for-solar-water-splitting-materials-and-challenges
#4
Chaoran Jiang, Savio J A Moniz, Aiqin Wang, Tao Zhang, Junwang Tang
It is widely accepted within the community that to achieve a sustainable society with an energy mix primarily based on solar energy we need an efficient strategy to convert and store sunlight into chemical fuels. A photoelectrochemical (PEC) device would therefore play a key role in offering the possibility of carbon-neutral solar fuel production through artificial photosynthesis. The past five years have seen a surge in the development of promising semiconductor materials. In addition, low-cost earth-abundant co-catalysts are ubiquitous in their employment in water splitting cells due to the sluggish kinetics of the oxygen evolution reaction (OER)...
June 23, 2017: Chemical Society Reviews
https://www.readbyqxmd.com/read/28642169/a-novel-method-to-quantify-base-substitution-mutations-at-the-10-6-per-bp-level-in-dna-samples
#5
Satoshi Yamashita, Naoko Iida, Hideyuki Takeshima, Naoko Hattori, Maeda Masahiro, Takayoshi Kishino, Reiko Nagano, Taichi Shimazu, Shoichiro Tsugane, Toshikazu Ushijima
Somatic base substitution mutations of frequencies at the 10(-6)/bp level are expected to be present in many biomedical samples, such as tissues exposed to carcinogenic factors and exhausted stem cells. However, measurement of such rare mutations has been very difficult in human DNA samples. Here, we invented the use of 100 copies of genomic DNA as a template for amplicon deep sequencing so that a real mutation in a single DNA molecule would be detected at a variant allele frequency of 1% while sequencing errors have less frequency...
June 19, 2017: Cancer Letters
https://www.readbyqxmd.com/read/28640391/selective-sweeps-of-mitochondrial-dna-can-drive-the-evolution-of-uniparental-inheritance
#6
Joshua R Christie, Madeleine Beekman
While the uniparental (or maternal) inheritance of mitochondrial DNA (mtDNA) is widespread, the reasons for its evolution remain unclear. Two main hypotheses have been proposed: selection against individuals containing different mtDNAs (heteroplasmy) and selection against "selfish" mtDNA mutations. Recently, uniparental inheritance was shown to promote adaptive evolution in mtDNA, potentially providing a third hypothesis for its evolution. Here we explore this hypothesis theoretically and ask if the accumulation of beneficial mutations provides a sufficient fitness advantage for uniparental inheritance to invade a population in which mtDNA is inherited biparentally...
June 22, 2017: Evolution; International Journal of Organic Evolution
https://www.readbyqxmd.com/read/28637851/island-rule-quantitative-genetics-and-brain-body-size-evolution-in-homo-floresiensis
#7
José Alexandre Felizola Diniz-Filho, Pasquale Raia
Colonization of islands often activate a complex chain of adaptive events that, over a relatively short evolutionary time, may drive strong shifts in body size, a pattern known as the Island Rule. It is arguably difficult to perform a direct analysis of the natural selection forces behind such a change in body size. Here, we used quantitative evolutionary genetic models, coupled with simulations and pattern-oriented modelling, to analyse the evolution of brain and body size in Homo floresiensis, a diminutive hominin species that appeared around 700 kya and survived up to relatively recent times (60-90 kya) on Flores Island, Indonesia...
June 28, 2017: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/28635965/identification-genealogical-structure-and-population-genetics-of-s-alleles-in-malus-sieversii-the-wild-ancestor-of-domesticated-apple
#8
X Ma, Z Cai, W Liu, S Ge, L Tang
The self-incompatibility (SI) gene that is specifically expressed in pistils encodes the SI-associated ribonuclease (S-RNase), functioning as the female-specificity determinant of a gametophytic SI system. Despite extensive surveys in Malus domestica, the S-alleles have not been fully investigated for Malus sieversii, the primary wild ancestor of the domesticated apple. Here we screened the M. sieversii S-alleles via PCR amplification and sequencing, and identified 14 distinct alleles in this species. By contrast, nearly 40 are present in its close wild relative, Malus sylvestris...
June 21, 2017: Heredity
https://www.readbyqxmd.com/read/28634255/population-genetic-structure-of-bromus-tectorum-in-the-mountains-of-western-north-america
#9
Spencer Arnesen, Craig E Coleman, Susan E Meyer
PREMISE OF THE STUDY: Invasive species are often initially restricted to a narrow range and may then expand through any of multiple mechanisms including phenotypic plasticity, in situ evolution, or selection on traits preadapted for new habitats. Our study used population genetics to explore possible processes by which the highly selfing invasive annual grass Bromus tectorum has expanded into montane environments. METHODS: We used 69 single nucleotide polymorphic (SNP) markers to genotype ca...
June 20, 2017: American Journal of Botany
https://www.readbyqxmd.com/read/28630332/evolutionary-strata-on-young-mating-type-chromosomes-despite-the-lack-of-sexual-antagonism
#10
Sara Branco, Hélène Badouin, Ricardo C Rodríguez de la Vega, Jérôme Gouzy, Fantin Carpentier, Gabriela Aguileta, Sophie Siguenza, Jean-Tristan Brandenburg, Marco A Coelho, Michael E Hood, Tatiana Giraud
Sex chromosomes can display successive steps of recombination suppression known as "evolutionary strata," which are thought to result from the successive linkage of sexually antagonistic genes to sex-determining genes. However, there is little evidence to support this explanation. Here we investigate whether evolutionary strata can evolve without sexual antagonism using fungi that display suppressed recombination extending beyond loci determining mating compatibility despite lack of male/female roles associated with their mating types...
June 19, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28628526/determinants-of-hiv-1-cd4-independent-brain-adaptation
#11
Madina Shakirzyanova, Xiang-Peng Kong, Cecilia Cheng-Mayer
BACKGROUND: HIV-1 is known to adapt to the local environment in its usage of receptors and it can become CD4 independent in the brain where the receptor is scarce. This adaptation is through amino acid variations, but the patterns of such variation are not yet well understood. Given that infection of long-lived CD4-low and CD4-negative cells in anatomic compartments such as the brain expand cell tropism in vivo and may serve as potential viral reservoirs that pose challenge for HIV eradication, understanding the evolution to CD4-independence and envelope conformation associated with infection in the absence of CD4 will not only broaden our insights into HIV pathogenesis, but may guide functional cure strategies as well...
June 15, 2017: Journal of Acquired Immune Deficiency Syndromes: JAIDS
https://www.readbyqxmd.com/read/28626616/discrimination-of-picea-chihuahuana-martinez-populations-on-the-basis-of-climatic-edaphic-dendrometric-genetic-and-population-traits
#12
Iliana Karina Dominguez-Guerrero, Samantha Del Rocío Mariscal-Lucero, José Ciro Hernández-Díaz, Berthold Heinze, José Ángel Prieto-Ruiz, Christian Wehenkel
BACKGROUND: Picea chihuahuana, which is endemic to Mexico, is currently listed as "Endangered" on the Red List. Chihuahua spruce is only found in the Sierra Madre Occidental (SMO), Mexico. About 42,600 individuals are distributed in forty populations. These populations are fragmented and can be classified into three geographically distinct clusters in the SMO. The total area covered by P. chihuahuana populations is less than 300 ha. A recent study suggested assisted migration as an alternative to the ex situ conservation of P...
2017: PeerJ
https://www.readbyqxmd.com/read/28625542/analysis-of-the-codon-usage-of-the-orf2-gene-of-feline-calicivirus
#13
Minghui Zang, Wanting He, Fanshu Du, Gongjian Wu, Bohao Wu, Zhenlei Zhou
Feline calicivirus (FCV) is a highly prevalent pathogen of the domestic cat that causes acute infections of the oral and upper respiratory tract. The E region of the ORF2 protein is responsible for the induction of virus-neutralizing antibodies, thus it is important to understand the codon usage of this gene. Here, analysed 90 coding sequences of ORF2 and show that it undergoes a low codon usage bias. In addition, although mutational bias is one of the factors shaping the codon usage bias of this gene, natural selection plays a more significant role...
June 16, 2017: Infection, Genetics and Evolution
https://www.readbyqxmd.com/read/28623373/metabolic-and-evolutionary-patterns-in-the-extremely-acidophilic-archaeon-ferroplasma-acidiphilum-y-t
#14
Olga V Golyshina, Hai Tran, Oleg N Reva, Sofia Lemak, Alexander F Yakunin, Alexander Goesmann, Taras Y Nechitaylo, Violetta LaCono, Francesco Smedile, Alexei Slesarev, David Rojo, Coral Barbas, Manuel Ferrer, Michail M Yakimov, Peter N Golyshin
Ferroplasmaceae represent ubiquitous iron-oxidising extreme acidophiles with a number of unique physiological traits. In a genome-based study of Ferroplasma acidiphilum Y(T), the only species of the genus Ferroplasma with a validly published name, we assessed its central metabolism and genome stability during a long-term cultivation experiment. Consistently with physiology, the genome analysis points to F. acidiphilum Y(T) having an obligate peptidolytic oligotrophic lifestyle alongside with anaplerotic carbon assimilation...
June 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28621685/active-evolution-of-memory-b-cells-specific-to-viral-gh-gl-pul128-130-131-pentameric-complex-in-healthy-subjects-with-silent-human-cytomegalovirus-infection
#15
Lin Xia, Aimin Tang, Weixu Meng, Daniel C Freed, Linling He, Dai Wang, Fengsheng Li, Leike Li, Wei Xiong, Xun Gui, Robbie D Schultz, Haotai Chen, Xi He, Ryan Swoyer, Sha Ha, Yaping Liu, Charles D Morris, Yu Zhou, I-Ming Wang, Qinjian Zhao, Wenxin Luo, Ningshao Xia, Amy S Espeseth, Daria J Hazuda, Richard E Rupp, Alan D Barrett, Ningyan Zhang, Jiang Zhu, Tong-Ming Fu, Zhiqiang An
Human cytomegalovirus (HCMV) can cause life-threatening infection in immunosuppressed patients, and in utero infection that may lead to birth defects. No vaccine is currently available. HCMV infection in healthy subjects is generally asymptomatic, and virus persists as latent infection for life. Host immunity is effective against reactivation and super-infection with another strain. Thus, vaccine candidates able to elicit immune responses similar to those of natural infection may confer protection. Since neutralization is essential for prophylactic vaccines, it is important to understand how antiviral antibodies are developed in natural infection...
June 3, 2017: Oncotarget
https://www.readbyqxmd.com/read/28616197/production-of-plumage-ornaments-among-males-and-females-of-two-closely-related-tropical-passerine-bird-species
#16
Erik D Enbody, Samantha M Lantz, Jordan Karubian
The evolution of elaborate secondary sexual traits (i.e., ornaments) is well-studied in males but less so in females. Similarity in the appearance of ornaments between males and females supports the view that female ornaments arise as a neutral byproduct of selection on male traits due to genetic correlation between sexes, but recent research suggests an adaptive function of female ornaments in at least some contexts. Information on the degree to which production of ornaments differs between the sexes can shed light on these alternative perspectives...
June 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28616068/genetic-diversity-and-structure-of-lolium-perenne-ssp-multiflorum-in-california-vineyards-and-orchards-indicate-potential-for-spread-of-herbicide-resistance-via-gene-flow
#17
Elizabeth Karn, Marie Jasieniuk
Management of agroecosystems with herbicides imposes strong selection pressures on weedy plants leading to the evolution of resistance against those herbicides. Resistance to glyphosate in populations of Lolium perenne L. ssp. multiflorum is increasingly common in California, USA, causing economic losses and the loss of effective management tools. To gain insights into the recent evolution of glyphosate resistance in L. perenne in perennial cropping systems of northwest California and to inform management, we investigated the frequency of glyphosate resistance and the genetic diversity and structure of 14 populations...
July 2017: Evolutionary Applications
https://www.readbyqxmd.com/read/28612461/oxygen-vacancy-engineering-of-co3o4-nanocrystals-via-constructing-coupled-interface-with-metal-supports-for-promoting-water-oxidation-in-neutral-electrolyte
#18
Jun-Jun Zhang, Hong-Hui Wang, Tian-Jian Zhao, Ke-Xin Zhang, Xiao Wei, Xin-Hao Li, Shin-Ichi Hirano, Jie-Sheng Chen
Oxygen vacancies could help to capture oxygen-containing species and act as active centers for oxygen evolution reaction (OER). Unfortunately, effective methods for generating a rich amount of oxygen vacancies on the surface of various nanocatalysts are rather limited. In this work, we described an effective way to generate oxygen vacancy-rich surface of transition metal oxides, exemplified with Co3O4 here, simply by constructing highly coupled interface of ultra-fine Co3O4 nanocrystals and metallic Ti. Impressively, the amounts of oxygen vacancy on the surface of Ti@Co3O4 far surpassed the reported values of the Co3O4 modified even under highly critical conditions...
June 14, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28610823/pre-vaccination-evolution-of-antibodies-among-infants-0-3-and-6months-of-age-a-longitudinal-analysis-of-measles-enterovirus-71-and-coxsackievirus-16
#19
Chuanxi Fu, Jichuan Shen, Long Lu, Yajing Li, Yimin Cao, Ming Wang, Sen Pei, Zhicong Yang, Qing Guo, Jeffrey Shaman
BACKGROUND: Due to waning levels of maternal antibodies (measles; enterovirus 71, EV71; and coxsackievirus A16, CoxA16), some infants may lose protection against infection prior to vaccination. Using a longitudinal design, we examine how maternal antibody levels evolve over time in infants prior to vaccination. METHODS: In 2013-2014, we collected sera at ages 0, 3 and 6months from infants. We assayed for levels of measles IgG antibody (717, 233 and 75 sample sera tested at months 0, 3 and 6, respectively), and neutralizing antibodies for EV71 and CoxA16 (225, 217, and 72)...
June 10, 2017: Vaccine
https://www.readbyqxmd.com/read/28608888/cyclometalated-ir-iii-complexes-based-on-2-2-4-difluorophenyl-pyridine-and-2-2-2-phenyl-1h-imidazole-4-5-diyl-dipyridine-acid-base-induced-structural-transformation-and-luminescence-switching-and-photocatalytic-activity-for-hydrogen-evolution
#20
Tai-Bao Gao, Qianwenhao Fan, Zhen-Tao Yu, Deng-Ke Cao
Based on ligands dfppyH and pidpyH, cyclometalated Ir(iii) complexes [Ir(dfppy)2(pidpyH)](PF6) (1·PF6) and [Ir(dfppy)2(pidpy)] (2) have been synthesized. The crystal structures indicate that each {Ir(dfppy)2}(+) unit is coordinated by a neutral ligand pidpyH in 1·PF6, while by a pidpy(-) anion in 2. The packing structure of 1·PF6 only exhibits electrostatic interactions and van der Waals interactions among [Ir(dfppy)2(pidpyH)](+) cations and PF6(-) ions. In contrast, the neighboring molecules in 2 are linked into a supramolecular chain structure through aromatic stacking interactions between two dfppy(-) ligands...
June 13, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
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