Valpha and Vbeta public repertoires are highly conserved in terminal deoxynucleotidyl transferase-deficient mice

T cell repertoires observed in response to immunodominant and subdominant peptides include private, i.e., specific for each individual, as well as public, i.e., common to all mice or humans of the same MHC haplotype, Valpha-Jalpha and Vbeta-Dbeta-Jbeta rearrangements. To measure the impact of N-region diversity on public repertoires, we have characterized the alphabeta TCRs specific for several CD4 or CD8 epitopes of wild-type mice and of mice deficient in the enzyme TdT. We find that V, (D), J usage identified in public repertoires is strikingly conserved in TdT(o/o) mice, even for the CDR3 loops which are shorter than those found in TdT(+/+) animals. Moreover, the 10- to 20-fold decrease in alphabeta T cell diversity in TdT(o/o) mice did not prevent T cells from undergoing affinity maturation during secondary responses. A comparison of the CDR3beta in published public and private repertoires indicates significantly reduced N-region diversity in public CDR3beta. We interpret our findings as suggesting that public repertoires are produced more efficiently than private ones by the recombination machinery. Alternatively, selection may be biased in favor of public repertoires in the context of the interactions between TCR and MHC peptide complexes and we hypothesize that MHCalpha helices are involved in the selection of public repertoires.     

A new fossil bird from the Early Cretaceous of Gansu Province,northwestern China

We report on the discovery of an Early Cretaceous bird from northwestern Gansu Province, in northwestern China. Represented by a nearly complete left wing and shoulder girdle the size of a rock dove, the new bird was quarried from laminated yellowish mudstones of the Xiagou Formation (Xinminpu Group) near Changma, in the Jiuquan area. These deposits have previously yielded the only known specimen of Gansus yumenensis, a basal ornithuromorph represented by the distal half of a hind limb with long and slender digits. Several derived characters of the new occurrence supports its allocation within Enantiornithes: (1) a convex lateral margin of the coracoid, (2) a minor metacarpal that projects distally more than the major metacarpal and (3) a proximal phalanx of the major digit longer than the intermediate (second) phalanx. The general proportions of the wing suggest it was a flier comparable to most other known enantiornithine birds. Although, direct comparisons between the new fossil and Gansus are not possible, phylogenetic based inferences supports their placement into two different clades. While the new fossil falls definitively within the enantiornithines, G. Yumenensis falls within the ornithuromorphs. The new occurrence thus adds to the taxonomic diversity of Early Cretaceous birds from Gansu Province in particular and central Asia in general.     

Review: Anaerobic treatment of municipal sanitary landfill leachates: the problem of refractory and toxic components

The wide use of municipal sanitary landfills has drawn attention to the leaching effluent generated, this may be problematic to the site's environment, whether by infiltration or other contaminating modes. Anaerobic digestion has been shown to be one of the most efficient systems with which to treat this type of effluent. This article reviews the techniques used by different authors for leachate characterization, specifically related to refractory and toxic components and their effect on anaerobic treatability. In addition, it covers the treatment of refractory organics, organic and inorganic toxic materials and the nutrient balance for adequate system operation. The main conclusions are that there is ample availability of methods by which to identify the different components present in leachates as well as for their toxicity assessment and that nutrients are in general available in sufficient amounts. Treatability studies are presented which are shown to be of general value and can be used in a straightforward manner.     

Polyandry Has No Detectable Mortality Cost in Female Mammals

In several taxonomic groups, females mate with several males during a single reproductive cycle. Although there is evidence that polyandry provides some benefits to females, it often involves mortality costs. However, empirical evidences of mortality costs of polyandry have so far been reported only in invertebrates. Whether polyandry has mortality costs in vertebrates is currently unknown. In the present study, we aimed to fill the gap by investigating the relationships between the level of polyandry (measured either by male relative testes mass or the percentage of multiple paternities) and female patterns of mortality across mammals. While we found that the two metrics of female mortality co-varied with pace of life, we did not find any evidence that polyandry leads to either decreased median lifespan or increased aging rate in mammals. We discuss such an absence of detectable mortality costs of polyandry in female mammals in light of recent advances in the study of mammalian reproductive biology and life-history tactics.     

Association of MITF loci with coat color spotting patterns in Ethiopian cattle

The genetics of coat color have been the focus of investigation for decades because beyond its aesthetic values, coat color is associated with thermo-tolerance, production and health traits. Despite the fascinating coat color phenotypes observed in Ethiopian cattle populations, up to now, there are no studies performed to identify and characterize polymorphisms associated with such variation at the genome level. In an attempt to identify and map the genetic basis of coat color variation in Ethiopian cattle, a genome-wide association study (GWAS), selection signatures test and network analysis were performed in 187 cattle populations genotyped on Illumina high-density chip. Loci significant at the genome-wide level (P ≤ 8.29 × 10^?7) and show selection signals (F _ST  ? 5SNP window = 0.13) were mainly localized on BTA22 (31.53–31.99) within the MITF gene. Network and functional annotation clustering analyses revealed that the candidate genes are involved in important pathways including melanogenesis. The results of the present study suggest a role of the MITF gene and its interaction with other genes in determining the spotting patterns observed in the Begait and Fogera cattle populations.     

Sequential reactors for the removal of endocrine disrupting chemicals by laccase immobilized onto fumed silica microparticles

Abstract

The main objective of this study is the evaluation of the capability of laccase from Myceliophthora thermophila immobilized on fumed silica microparticles (fsMP) for the removal of endocrine disrupting chemicals (EDCs) in two enzymatic reactor configurations. This type of support can also be magnetized to allow the straightforward separation of the biocatalyst under a magnetic field. The support exhibited excellent biocompatibility with the enzyme, superior tolerance to pH and temperature as well as improved stability in comparison with the free enzyme, even in the presence of organic solvents and enzyme inhibitors. The technical feasibility of the removal of EDCs by immobilized laccase was assessed in two types of enzymatic reactors operated in sequential mode: a membrane reactor using fsMP-laccase and a reactor with magnetic separation using magnetized fsMP-laccase. The extent of transformation for the target compounds: bisphenol A (BPA) and 17β-estradiol (E2) was high and comparable to free laccase in both systems (up to 80%). The possibility of reusing the immobilized enzyme, especially for magnetized supports, offers an interesting approach in the development of enzyme based processes for the biotransformation of emerging pollutants.     

Enzymatic reactors for the removal of recalcitrant compounds in wastewater

Abstract

Enzymatic treatments based on oxidative enzymes, such as peroxidases, laccases and tyrosinases, have been proposed as an alternative to conventional methods to remove a broad range of contaminants present in wastewater. The aim of this study is to discuss existing technologies for the removal of pollutants based on the use of oxidative enzymes, including a discussion on the most important factors affecting the efficiency of the proposed systems. Factors involved in the catalytic cycle of the enzyme (biocatalyst, substrates and mediators), the addition of certain components to the reaction medium (additives, surfactants or solvents) as well as operational parameters (temperature, pH or agitation) will be discussed. Finally, two types of reactors: one-stage and two-stage enzymatic membrane reactors, especially designed for the treatment of micropollutants present in secondary effluents, will be described in detail.     

Analyses of karyotype by G-banding and high-resolution microarrays in a gender dysphoria population

Gender Dysphoria is characterized by a marked incongruence between the cerebral sex and biological sex. To investigate the possible influence of karyotype on the etiology of Gender Dysphoria we carried out the cytogenetic analysis of karyotypes in 444 male-to-females (MtFs) and 273 female-to-males (FtMs) that attended the Gender Identity Units of Barcelona and Málaga (Spain) between 2000 and 2016. The karyotypes from 23 subjects (18 MtFs and 5 FtMs) were also analysed by Affymetrix CytoScan? high-density (HD) arrays. Our data showed a higher incidence of cytogenetic alterations in Gender Dysphoria (2.65%) than in the general population (0.53%) (p?<?0.0001). When G-banding was performed, 11 MtFs (2.48%) and 8 FtMs (2.93%) showed a cytogenetic alteration. Specifically, Klinefelter syndrome frequency was significantly higher (1.13%) (p?<?0.0001), however Turner syndrome was not represented in our sample (p?<?0.61). At molecular level, HD microarray analysis revealed a 17q21.31 microduplication which encompasses the gene KANSL1 (MIM612452) in 5 out of 18 MtFs and 2 out of 5 FtMs that corresponds to a copy-number variation region in chromosome 17q21.31. In conclusion, we confirm a significantly high frequency of aneuploidy, specifically Klinefelter syndrome and we identified in 7 out of 23 GD individuals the same microduplication of 572 Kb which encompasses the KANSL1 gene.