Woodland management at the Swedish middle Neolithic site of Alvastra? A new perspective

It is often argued that the repetitive removal of branches to improve the quantity and the quality of wood, i.e. woodland management, has been practiced in Europe from the Mesolithic and/or Neolithic onwards. The Neolithic pile dwelling of Alvastra in Sweden has been mentioned in textbooks as a classical example of this practice. The conclusion about woodland management at Alvastra was primarily based on palynological data, which do not provide any direct evidence. Is it correct to conclude that woodland management was practiced at Alvastra? To investigate that, this paper reviews the previous arguments and interpretations, focusing on wood data, and by comparing archaeological data with modern wood data. First, the assemblage of vertical posts from the latest excavations at Alvastra include a wide range of taxa, showing opportunistic use of the woody vegetation. Second, while the dendrochronological analysis of Quercus and Ulmus carried out in the 80 s has clearly indicated that the trees used for the posts grew under highly similar conditions and that particularly many Quercus trees started to grow more or less at the same time, the reason for the partially simultaneous start of growth remains unknown, and the posts used for the construction of the site do not provide evidence of repetitive removal of trunks from stools. Finally, analysis of the age/diameter data of the Corylus wood indicates the use of branches from unmanaged vegetation, while age data of Salix do not support management either. In conclusion, the data do not support the hypothesis of woodland management at Neolithic Alvastra, and it is most likely that people did not practice woodland management. This outcome corresponds to the conclusions in some of the previous publications about the site.

     

Surveys reveal a complex association of phytoplasmas and viruses with the blueberry stunt disease on Canadian blueberry farms

Surveys for phytoplasmas and viruses were conducted during September 2014 and 2015 on highbush blueberry farms in the Région Montérégie, Quebec. Total DNA and RNA were extracted from blueberry bushes showing blueberry stunt (BBS) symptoms and from symptomless blueberry bushes, and utilised as templates for PCR and RT‐PCR assays, respectively. Phytoplasma DNA was amplified with universal phytoplasma primers that target the 16S rRNA, secA and secY genes from 12 out of 40 (30%) plants tested. Based on 16S rRNA, secA and secY gene sequence identity, phylogenetic clustering, actual and in silico RFLP analyses, phytoplasma strains associated with BBS disease in Quebec were identified as ‘Candidatus Phytoplasma asteris’‐related strains, closely related to the BBS Michigan phytoplasma strain (16SrI‐E). The secY gene sequence‐based single nucleotide polymorphism analysis revealed that one of the BBS phytoplasma strains associated with a leaf marginal yellowing is a secY‐I RFLP variant of the subgroup 16SrI‐E. Two viruses were detected in blueberry bushes. The Blueberry Red Ringspot Virus (BRRV) was found in a single infection in the cultivar Bluecrop with no apparent typical BRRV symptoms. The Tobacco Ringspot Virus (TRSV) was found singly infecting blueberry plants and co‐infecting a BBS phytoplasma‐infected blueberry cv. Bluecrop plant. This is the first report of TRSV in the cv. Bluecrop in Quebec. The Quebec BBS phytoplasma strain was identified in the leafhopper Graphocephala fennahi, which suggests that G. fennahi may be a potential vector for the BBS phytoplasma. The BBS disease shows a complex aetiology and epidemiology; therefore, prompt actions must be developed to support focused BBS integrated management strategies.     

Micro- and macrorheology of jellyfish extracellular matrix

Mechanical properties of the extracellular matrix (ECM) play a key role in tissue organization and morphogenesis. Rheological properties of jellyfish ECM (mesoglea) were measured in vivo at the cellular scale by passive microrheology techniques: microbeads were injected in jellyfish ECM and their Brownian motion was recorded to determine the mechanical properties of the surrounding medium. Microrheology results were compared with macrorheological measurements performed with a shear rheometer on slices of jellyfish mesoglea. We found that the ECM behaved as a viscoelastic gel at the macroscopic scale and as a much softer and heterogeneous viscoelastic structure at the microscopic scale. The fibrous architecture of the mesoglea, as observed by differential interference contrast and scanning electron microscopy, was in accord with these scale-dependent mechanical properties. Furthermore, the evolution of the mechanical properties of the ECM during aging was investigated by measuring microrheological properties at different jellyfish sizes. We measured that the ECM in adult jellyfish was locally stiffer than in juvenile ones. We argue that this stiffening is a consequence of local aggregations of fibers occurring gradually during aging of the jellyfish mesoglea and is enhanced by repetitive muscular contractions of the jellyfish.     

Anti-citrullinated fibronectin antibodies in rheumatoid arthritis are associated with human leukocyte antigen-DRB1 shared epitope alleles

Introduction

Fibronectin is one of the most abundant proteins present in the inflamed joint. Here, we characterized the citrullination of fibronectin in the joints of rheumatoid arthritis (RA) patients and studied the prevalence, epitope specificity and human leukocyte antigen (HLA) association of autoantibodies against citrullinated fibronectin in RA.

Methods

Citrullinated residues in fibronectin isolated from RA patient synovial fluid were identified by mass spectrometry. The corresponding citrullinated and non-citrullinated peptides were synthesized and used to analyze the presence of autoantibodies to these peptides in RA sera and sera from other diseases and healthy controls by ELISA. The data were compared with risk factors like shared epitope HLA alleles and smoking, and with clinical features.

Results

Five citrullinated residues were identified in fibronectin from RA synovial fluid. RA sera reacted in a citrulline-dependent manner with two out of four citrullinated fibronectin peptides, one of which contains two adjacent citrulline residues, in contrast to non-RA sera, which were not reactive. The most frequently recognized peptide (FN-Cit_1035,1036, LTVGLTXXGQPRQY, in which × represents citrulline) was primarily targeted by anti-CCP (cyclic citrullinated peptide) 2-positive RA patients. Anti-FN-Cit_1035,1036 autoantibodies were detected in 50% of established anti-CCP2-positive RA patients and in 45% of such patients from a early arthritis clinic. These antibodies appeared to be predominantly of the immunoglobulin G (IgG) isotype and to be associated with HLA shared epitope alleles (odds ratio = 2.11).

Conclusions

Fibronectin in the inflamed synovia of RA patients can be citrullinated at least at five positions. Together with the flanking amino acids, three of these citrullinated residues comprise two epitopes recognized by RA autoantibodies. Anti-citrullinated fibronectin peptide antibodies are associated with HLA shared epitope alleles.     

Synthesis and evaluation of homodimeric GnRHR antagonists having a rigid bis-propargylated benzene core

The fact that GPCRs might function in a dimeric fashion is currently well accepted. For GnRHR, a GPCR that regulates gonadotropin release, there is evidence that the receptor also functions as a dimer. We here describe the design and synthesis of a set of dimeric GnRHR antagonists in order to understand the interaction of dimeric ligands to the receptor and to address the question whether GnRHR dimerization is a prerequisite for signalling. Biological evaluation of the compounds shows no discrimination between monomeric and dimeric-ligands in respect to binding affinities, however, the dimeric ligands appear to have different functional properties.     

New applications and performance of bioelectrochemical systems

Bioelectrochemical systems (BESs) are emerging technologies which use microorganisms to catalyze the reactions at the anode and/or cathode. BES research is advancing rapidly, and a whole range of applications using different electron donors and acceptors has already been developed. In this mini review, we focus on technological aspects of the expanding application of BESs. We will analyze the anode and cathode half-reactions in terms of their standard and actual potential and report the overpotentials of these half-reactions by comparing the reported potentials with their theoretical potentials. When combining anodes with cathodes in a BES, new bottlenecks and opportunities arise. For application of BESs, it is crucial to lower the internal energy losses and increase productivity at the same time. Membranes are a crucial element to obtain high efficiencies and pure products but increase the internal resistance of BESs. The comparison between production of fuels and chemicals in BESs and in present production processes should gain more attention in future BES research. By making this comparison, it will become clear if the scope of BESs can and should be further developed into the field of biorefineries.     

Extensive sharing of MHC class II alleles between rhesus and cynomolgus macaques

In contrast to rhesus monkeys, substantial knowledge on cynomolgus monkey major histocompatibility complex (MHC) class II haplotypes is lacking. Therefore, 17 animals, including one pedigreed family, were thoroughly characterized for polymorphic Mhc class II region genes as well as their mitochondrial DNA (mtDNA) sequences. Different cynomolgus macaque populations appear to exhibit unique mtDNA profiles reflecting their geographic origin. Within the present panel, 10 Mafa-DPB1, 14 Mafa-DQA1, 12 Mafa-DQB1, and 35 Mafa-DRB exon 2 sequences were identified. All of these alleles cluster into lineages that were previously described for rhesus macaques. Moreover, about half of the Mafa-DPB1, Mafa-DQA1, and Mafa-DQB1 alleles and one third of the Mafa-DRB exon 2 sequences are identical to rhesus macaque orthologues. Such a high level of Mhc class II allele sharing has not been reported for primate species. Pedigree analysis allowed the characterization of nine distinct Mafa class II haplotypes, and seven additional ones could be deduced. Two of these haplotypes harbor a duplication of the Mafa-DQB1 locus. Despite extensive allele sharing, rhesus and cynomolgus monkeys do not appear to possess identical Mhc class II haplotypes, thus illustrating that new haplotypes were generated after speciation by recombination-like processes.     

Cancer genetics and its "different faces of autonomy"

In this article we discuss the development of a practice of screening, preventive treatment, and presymptomatic testing for individuals at risk of Familial Adenomatous Polyposis (FAP), a specific hereditary predisposition for colon cancer. We describe this development as a process of co-evolution, showing how this practice has been gradually taking shape in a new network of actors, routines, rules, institutions and technologies. We further argue that, looking at the emergence and transformation of this practice, we can distinguish two different regimes: a regime of prevention and a regime of self-determination. In each of these regimes the autonomy of patients and individuals at risk is shaped in a different way, that is, through a different complex of ideals, procedures, institutions, technologies, and routines. In our view, the interference between these two regimes is an important characteristic of the emergent new genetics and is reflected in the growing debate about non-directivity in genetic counselling. However, as our argument implies, when facing the challenges of the new genetics we should not restrict the debate to the quality and ethics of counselling, but extend our view to the whole complex of elements and activities which shapes individual autonomy in the context of different regimes.