Detrimental role for human high temperature requirement serine protease A1 (HTRA1) in the pathogenesis of intervertebral disc (IVD) degeneration

Human HTRA1 is a highly conserved secreted serine protease that degrades numerous extracellular matrix proteins. We have previously identified HTRA1 as being up-regulated in osteoarthritic patients and as having the potential to regulate matrix metalloproteinase (MMP) expression in synovial fibroblasts through the generation of fibronectin fragments. In the present report, we have extended these studies and investigated the role of HTRA1 in the pathogenesis of intervertebral disc (IVD) degeneration. HTRA1 mRNA expression was significantly elevated in degenerated disc tissue and was associated with increased protein levels. However, these increases did not correlate with the appearance of rs11200638 single nucleotide polymorphism in the promoter region of the HTRA1 gene, as has previously been suggested. Recombinant HTRA1 induced MMP production in IVD cell cultures through a mechanism critically dependent on MEK but independent of IL-1β signaling. The use of a catalytically inactive mutant confirmed these effects to be primarily due to HTRA1 serine protease activity. HTRA1-induced fibronectin proteolysis resulted in the generation of various sized fragments, which when added to IVD cells in culture, caused a significant increase in MMP expression. Furthermore, one of these fragments was identified as being the amino-terminal fibrin- and heparin-binding domain and was also found to be increased within HTRA1-treated IVD cell cultures as well as in disc tissue from patients with IVD degeneration. Our results therefore support a scenario in which HTRA1 promotes IVD degeneration through the proteolytic cleavage of fibronectin and subsequent activation of resident disc cells.     

The biofilm formation defect of a Bacillus subtilis flotillin‐defective mutant involves the protease FtsH

Biofilm formation in Bacillus subtilis requires the differentiation of a subpopulation of cells responsible for the production of the extracellular matrix that structures the biofilm. Differentiation of matrix‐producing cells depends, among other factors, on the FloT and YqfA proteins. These proteins are present exclusively in functional membrane microdomains of B. subtilis and are homologous to the eukaryotic lipid raft‐specific flotillin proteins. In the absence of FloT and YqfA, diverse proteins normally localized to the membrane microdomains of B. subtilis are not functional. Here we show that the absence of FloT and YqfA reduces the level of the septal‐localized protease FtsH. The flotillin homologues FloT and YqfA are occasionally present at the midcell in exponentially growing cells and the absence of FloT and YqfA negatively affects FtsH concentration. Biochemical experiments indicate a direct interaction between FloT/YqfA and FtsH. Moreover, FtsH is essential for the differentiation of matrix producers and hence, biofilm formation. This molecular trigger of biofilm formation may therefore be used as a target for the design of new biofilm inhibitors. Accordingly, we show that the small protein SpoVM, known to bind to and inhibit FtsH activity, inhibits biofilm formation in B. subtilis and other distantly related bacteria.     

Isolation and characterization of three Mammalian orthoreoviruses from European bats

In recent years novel human respiratory disease agents have been described in South East Asia and Australia. The causative pathogens were classified as pteropine orthoreoviruses with strong phylogenetic relationship to orthoreoviruses of flying foxes inhabiting these regions. Subsequently, a zoonotic bat-to-human transmission has been assumed. We report the isolation of three novel mammalian orthoreoviruses (MRVs) from European bats, comprising bat-borne orthoreovirus outside of South East Asia and Australia and moreover detected in insectivorous bats (Microchiroptera). MRVs are well known to infect a broad range of mammals including man. Although they are associated with rather mild and clinically unapparent infections in their hosts, there is growing evidence of their ability to also induce more severe illness in dogs and man. In this study, eight out of 120 vespertilionid bats proved to be infected with one out of three novel MRV isolates, with a distinct organ tropism for the intestine. One isolate was analyzed by 454 genome sequencing. The obtained strain T3/Bat/Germany/342/08 had closest phylogenetic relationship to MRV strain T3D/04, isolated from a dog. These novel reoviruses provide a rare chance of gaining insight into possible transmission events and of tracing the evolution of bat viruses.     

Analysis of functional germline polymorphisms for prediction of response to anthracycline-based neoadjuvant chemotherapy in breast cancer

To elucidate the role of predictive factors on individual's drug response, based on genetic variation, we examined the association between eight germline polymorphisms in genes involved in protection against oxidative stress, apoptosis, oncogenic transformation, proliferation, immune response and DNA repair (TP53, NQO1, IL6, TLR4 and XRCC1) and the pathological response to anthracycline-based neoadjuvant chemotherapy in 70 patients with breast cancer. The DNA was genotyped for eight polymorphisms in five genes (TP53, NQO1, IL6, TLR4 and XRCC1) by 5'-exonuclease (TaqMan?) technology. Fisher's exact test was used to evaluate the association between genotype, clinicopathological parameters and pathological response. A good pathological response, defined as a pathological complete response or residual isolated invasive tumor cells, was found significantly more frequently for estrogen (ER) and progesterone receptor (PR) negative breast carcinomas compared to ER and PR positive and ER or PR positive carcinomas, respectively (43.5 vs. 37.5 and 10.3?%, p?=?0.006), and was significantly associated with high tumor grade (G3) (p?=?0.002). A non-significant trend towards a good pathological response was shown in patients carrying the Arg/Arg or Arg/Pro TP53 codon 72 gene variant compared to those harboring the Pro/Pro variant (17.6 or 37.9?% vs. 0; p?=?0.071). No association was found between NQO1 Pro187Ser, IL6 -174G>C, TLR4 Asp299Gly and Thr399Ile, and XRCC1 Arg194Trp, Arg399Gln and Arg280His and pathological response. The present study shows hormone receptor status and tumor grade as predictors for pathological response to neoadjuvant anthracycline-based chemotherapy. Among various functional germline polymorphisms, a potential predictive value was only found for the TP53 Arg72Pro gene variant.     

Genetic and functional analyses of SHANK2 mutations suggest a multiple hit model of autism spectrum disorders

Autism spectrum disorders (ASD) are a heterogeneous group of neurodevelopmental disorders with a complex inheritance pattern. While many rare variants in synaptic proteins have been identified in patients with ASD, little is known about their effects at the synapse and their interactions with other genetic variations. Here, following the discovery of two de novo SHANK2 deletions by the Autism Genome Project, we identified a novel 421 kb de novo SHANK2 deletion in a patient with autism. We then sequenced SHANK2 in 455 patients with ASD and 431 controls and integrated these results with those reported by Berkel et al. 2010 (n = 396 patients and n = 659 controls). We observed a significant enrichment of variants affecting conserved amino acids in 29 of 851 (3.4%) patients and in 16 of 1,090 (1.5%) controls (P = 0.004, OR = 2.37, 95% CI = 1.23–4.70). In neuronal cell cultures, the variants identified in patients were associated with a reduced synaptic density at dendrites compared to the variants only detected in controls (P = 0.0013). Interestingly, the three patients with de novo SHANK2 deletions also carried inherited CNVs at 15q11–q13 previously associated with neuropsychiatric disorders. In two cases, the nicotinic receptor CHRNA7 was duplicated and in one case the synaptic translation repressor CYFIP1 was deleted. These results strengthen the role of synaptic gene dysfunction in ASD but also highlight the presence of putative modifier genes, which is in keeping with the “multiple hit model” for ASD. A better knowledge of these genetic interactions will be necessary to understand the complex inheritance pattern of ASD.     

Beaming into the Rat World: Enabling Real-Time Interaction between Rat and Human Each at Their Own Scale

Immersive virtual reality (IVR) typically generates the illusion in participants that they are in the displayed virtual scene where they can experience and interact in events as if they were really happening. Teleoperator (TO) systems place people at a remote physical destination embodied as a robotic device, and where typically participants have the sensation of being at the destination, with the ability to interact with entities there. In this paper, we show how to combine IVR and TO to allow a new class of application. The participant in the IVR is represented in the destination by a physical robot (TO) and simultaneously the remote place and entities within it are represented to the participant in the IVR. Hence, the IVR participant has a normal virtual reality experience, but where his or her actions and behaviour control the remote robot and can therefore have physical consequences. Here, we show how such a system can be deployed to allow a human and a rat to operate together, but the human interacting with the rat on a human scale, and the rat interacting with the human on the rat scale. The human is represented in a rat arena by a small robot that is slaved to the human’s movements, whereas the tracked rat is represented to the human in the virtual reality by a humanoid avatar. We describe the system and also a study that was designed to test whether humans can successfully play a game with the rat. The results show that the system functioned well and that the humans were able to interact with the rat to fulfil the tasks of the game. This system opens up the possibility of new applications in the life sciences involving participant observation of and interaction with animals but at human scale.     

Phenotypic plasticity in response to mechanical stress: hydrodynamic performance and fitness of four aquatic plant species

Plastic responses of plants exposed to mechanical stress can lead to modified, performance-enhancing, morphologies, sometimes accompanied by costs to reproduction. The capacity to present short-term plastic responses to current stress, the resulting performance (expected lower mechanical forces), and the costs of such responses to reproduction were tested for four aquatic plant species. Two ramets of the same genet were submitted to running vs standing water treatment. Traits describing the morphology, hydrodynamic performance and reproduction (sexual and vegetative) were measured. For one species, plastic responses led to reduced hydrodynamic forces, without apparent costs to reproduction, indicating that the plastic response could be beneficial for plant maintenance in stressful habitats. For two species, plastic responses were not associated with variations in performance and reproduction, possibly because of the low hydrodynamic forces experienced, even for morphologies produced under standing conditions. For one species, plastic responses were associated with a sharp decrease in sexual reproduction, without variations in performance, revealing the negative impact of currents over a short time scale. Species maintenance is linked to the capacity of individuals to tolerate mechanical forces. The contrasting responses to currents may be a key element for predicting community dynamics.     

Abiotic stresses increase plant regeneration ability

In disturbed habitats, vegetative regeneration is partly ruled by plant reserves and intrinsic growth rates. Under nutrient-limiting conditions, perennial plants tend to exhibit an increased allocation to storage organs. Under mechanically stressful conditions, plants also tend to increase allocation to below-ground biomass and storage organs. We tested whether those stresses acting differently on plants (nutrient level versus mechanical forces) led to similar effect on storage organs and regeneration ability. We measured, for an aquatic plant species, (1) the size and allocation to storage organs (stems) and (2) the regeneration ability of the storage organs. Plant stems were collected in 4 habitats ranked along a nutrient stress gradient, and having encountered null versus significant mechanical stress (flowing water). All stems were placed in similar neutral conditions and left for a period of 6 weeks before measuring their survival and growth. Dry mass allocation to the storage organ (stem) was higher in stressful habitats. Moreover, stress encountered by plants before the experiment significantly affected regeneration: stems of previously stressed plants (i.e. plants that had grown in nutrient-poor or mechanically stressful habitats) survived better than unstressed ones. Stems of plants having encountered mechanical stress before the experiment had increased growth in nutrient-rich habitats but reduced growth in the poorest habitats. These results demonstrate that regeneration could rely on the level of stress previously encountered by plants. Stress could lead to greater regeneration ability following mechanical failure. The possible mechanisms involved in these results are discussed.     

Welternährung im 21. Jahrhundert. Eine umfassende Herausforderung (Teil 1)

Nutrition of the world's population in the 21st century often appears as an unsolved problem. The challenges are bigger than an increase in agricultural production. From a brief review on the history of food production diverse aspects of the development become evident: innovations with their beneficial and non‐beneficial aspects, e.g. the, green revolution' increasing the rice yields on one hand and the number of landless people on the other. Great differences can be found in agricultural productivity: the yields of the presently area under the plough can be increased. Climate change impacts on the framework of agricultural production with losses and gains of arable land. The challenges of global nutrition cannot be met by innovations in plant breeding and cultivation alone. Socioeconomic factors, education, and health become increasingly important.