Expression profiles of the essential intermediate filament (IF) protein A2 and the IF protein C2 in the nematode Caenorhabditis elegans

The multigene family of intermediate filament (IF) proteins in Caenorhabditis elegans covers 11 members of which four (A1-3, B1) are essential for development. Suppression of a fifth gene (C2) results in a dumpy phenotype. Expression patterns of three essential genes (A1, A3, B1) were already reported. To begin to analyze the two remaining RNAi phenotypes we followed the expression of the A2 and C2 proteins. Expression of A2 mRNA starts in larval stage L1 and continues in the adult. Transgenic A2 promoter/gfp larvae strongly display GFP in the main body hypodermis but not in seam cells. This pattern and the muscle displacement/paralysis induced by RNAi silencing are consistent with the role of this protein in keeping the correct hypodermis/muscle relationship during development. IF protein C2 occurs in the cytoplasm and desmosomes of intestinal cells and in pharynx desmosomes. Expression of C2 starts in the late embryo and persists in all further stages. (C) 2002 Published by Elsevier Science Ireland Ltd

Inverse Dynamics Analysis of Youth Pitching Arm Kinetics Using Body Composition Imaging

This study’s objectives were to: (1) assess whether dual energy X-ray absorptiometry (DXA)-mass inverse dynamics (ID) alters predictions of youth pitching arm kinetics and (2) investigate correlations between kinetics and body composition. Eighteen 10- to 11-year-olds pitched 10 fastballs. DXA scans were conducted to obtain participant-specific upper arm, forearm, and hand masses. Pitching arm segment masses and kinetics calculated with scaled and DXA masses were compared with paired t-tests and correlations were investigated with linear regression. Hand (p \u3c 0.001) and upper arm (p \u3c 0.001) DXA masses were greater, while forearm (p \u3c 0.001) DXA masses were lesser, than their scaled masses. Shoulder compressive force (p \u3c 0.001), internal rotation torque (p \u3c 0.001), and horizontal adduction torque (p = 0.002) increased when using DXA masses. Shoulder compressive force correlated with body mass (p \u3c 0.001) and body mass index (BMI; p = 0.002) and elbow varus torque correlated with body mass (p \u3c 0.05). The main conclusions were that (1) using participant-specific mass ratios leads to different predictions of injury-related pitching arm kinetics and, thus, may improve our understanding of injury risk factors; and (2) pitching arm kinetics were correlated with body composition measures and a relatively high total body mass and/or BMI may increase shoulder and/or elbow injury risk

Isolation of pregnancy-associated glycoproteins (PAG) from water buffalo (Bubalus bubalis) placenta by use of Vicia villosa bound agarose affinity chromatography

The present study describes the isolation and characterisation of new PAG molecules extracted from mid- and late-pregnancy placentas in the water buffalo (Bubalis bubalis). After extraction, acid and ammonium sulphate precipitation and DEAE chromatography water buffalo PAG (wbPAG) were enriched by Vicia villosa agarose (VVA) affininity chromatography. As determined by Western blotting with anti-PAG-sera, apparent molecular masses of immunoreactive bands from VVA peaks ranged from 59.5 to 75.8 kDa and from 57.8 to 80.9 kDa in the mid- and late- pregnancy placenta respectively. Aminoterminal microsequencing of proteins allowed the identification of three distinct wbPAG sequences wich have ben deposed in the SwissProt database: RGSXLTIHPLRNIRDFFYUG (Acc. n. P85048), RGSXLTILPLRNIID (P85049) and RGSXLTHLPLRNI (P85050). Their comparison to those previously identified revealed that two of them were new since they have not been described yet. Our results confirm the suitability of VVA chromatography in enrichment of multiple PAG molecules expressed in buffalo placenta. Productions of specific antisera can be very useful in immonoistochemical and immunocyitochemical studies of PAG expression in fetomaternal interfaces. Purified native PAG are also required for development on specific immoassays (RIA/ELISA) currently used for pregnancy diagnosis and physiological investigation in farm animal

Development of a human knee joint finite element model to investigate cartilage stress during walking in obese and normal weight adults

Osteoarthritis (OA) is a degenerative condition characterized by the breakdown and loss of joint articular cartilage. While the cause of OA is not precisely known, obesity is a known risk factor [1]. Particular effort has gone towards understanding the relationship between obesity and knee OA because obesity is more strongly linked to OA at the knee than at any other lower extremity joint [2]. Although the relationship between obesity and knee OA is well established, the mechanism of pathogenesis is less understood. Excess body weight generates greater joint contact forces at the knee. However, obese individuals alter their gait, resulting in increased joint contact forces that are not proportional to body mass [3]. In this study, a partially validated knee joint finite element (FE) model was developed to predict cartilage loading during walking across individuals of varying adiposity. The model was used with kinematic and kinetic gait data to address the following hypotheses: 1) increased loading due to obesity will produce greater cartilage stress compared to the normal weight control; and 2) altered gait kinematics of obese individuals will alter the distribution of stress on the surface of the tibial cartilage

Human knee joint finite element model using a two bundle anterior cruciate ligament: Validation and gait analysis

Anterior cruciate ligament (ACL) deficient individuals are at a much higher risk of developing osteoarthritis (OA) compared to those with intact ACLs, likely due to altered biomechanical loading [1]. Research indicates the ACL is comprised of two “bundles”, the anteromedial (AM) and posterolateral (PL) bundles [2]. Although the function of both bundles is to restrain anterior tibial translation (ATT), each bundle has their own distinct range of knee flexion where they are most effective [3]. Articular cartilage contact stress measurements are difficult to measure in vivo. An alternative approach is to use knee joint finite element models (FEMs) to predict soft tissue stresses and strains throughout the knee. Initial and boundary conditions for these FEMs may be determined from knee joint kinematics estimated from motion analysis experiments. However, there is a lack of knee joint FEMs which include both AM and PL bundles to predict changes to articular cartilage contact pressures resulting from ACL injuries. The purpose of this study is to develop and validate a knee joint FEM using both AM and PL bundles and subsequently perform a gait analysis of varying ACL injuries

A cartilage growth mixture model for infinitesimal strains: solutions of boundary-value problems related to in vitro growth experiments

A cartilage growth mixture (CGM) model is linearized for infinitesimal elastic and growth strains. Parametric studies for equilibrium and nonequilibrium boundary-value problems representing the in vitro growth of cylindrical cartilage constructs are solved. The results show that the CGM model is capable of describing the main biomechanical features of cartilage growth. The solutions to the equilibrium problems reveal that tissue composition, constituent pre-stresses, and geometry depend on collagen remodeling activity, growth symmetry, and differential growth. Also, nonhomogeneous growth leads to nonhomogeneous tissue composition and constituent pre-stresses. The solution to the nonequilibrium problem reveals that the tissue is nearly in equilibrium at all time points. The results suggest that the CGM model may be used in the design of tissue engineered cartilage constructs for the repair of cartilage defects; for example, to predict how dynamic mechanical loading affects the development of nonuniform properties during in vitro growth. Furthermore, the results lay the foundation for future analyses with nonlinear models that are needed to develop realistic models of cartilage growth

Neuregulin 3 promotes excitatory synapse formation on hippocampal interneurons

Hippocampal GABAergic interneurons are crucial for cortical network function and have been implicated in psychiatric disorders. We show here that Neuregulin 3 (Nrg3), a relatively little investigated low-affinity ligand, is a functionally dominant interaction partner of ErbB4 in parvalbumin-positive (PV) interneurons. Nrg3 and ErbB4 are located pre- and postsynaptically, respectively, in excitatory synapses on PV interneurons in vivo. Additionally, we show that ablation of Nrg3 results in a similar phenotype as the one described for ErbB4 ablation, including reduced excitatory synapse numbers on PV interneurons, altered short-term plasticity, and disinhibition of the hippocampal network. In culture, presynaptic Nrg3 increases excitatory synapse numbers on ErbB4(+) interneurons and affects short-term plasticity. Nrg3 mutant neurons are poor donors of presynaptic terminals in the presence of competing neurons that produce recombinant Nrg3, and this bias requires postsynaptic ErbB4 but not ErbB4 kinase activity. Furthermore, when presented by non-neuronal cells, Nrg3 induces postsynaptic membrane specialization. Our data indicate that Nrg3 provides adhesive cues that facilitate excitatory neurons to synapse onto ErbB4(+) interneurons

Beyond values : how emotions, anthropomorphism, beliefs and knowledge relate to the acceptability of native and non‐native species management in cities

Managing non‐native species in cities is often controversial because these species can support both ecosystem services and disservices. Yet, how the acceptability of non‐native species management by the general public differs in relation to native species, to distance (i.e. close to residence and elsewhere) and among plants and animals is understudied. Furthermore, while values, beliefs and knowledge are often considered in this context, psychometric factors such as emotions and anthropomorphic views have received little attention. We surveyed 658 residents in Berlin, Germany, to assess (i) the acceptability of management actions differing in their severity for non‐native plants and animals compared to native species with similar traits, (ii) the influence of perceived distance of species (i.e. close to residence and elsewhere) and (iii) the predictive potential of psychometric (i.e. values, beliefs, self‐assessed knowledge, emotions and anthropomorphism) and socio‐demographic factors for this acceptability. Eradication (i.e. lethal control/removal) was generally the least accepted management action, but more accepted for non‐native than native species. Distance mattered for the acceptability of non‐native plant management with unspecified control action the most accepted management action close to residence. While values (self‐transcendence and conservation) mostly explained the acceptability of doing nothing and eradication, emotions related strongly to all management actions. Beliefs were more important than self‐assessed knowledge in relation to non‐native species management and beliefs about non‐native plants and animals were rated almost similar. Anthropomorphic views had predictive potential for plants and animals; that is, the stronger people held anthropomorphic views, the less they accepted eradication. Participants with a garden supported doing nothing with plants (native and non‐native) more than without. Results highlight the complexity of factors underlying the acceptability of management actions on species in cities. While values, beliefs and self‐assessed knowledge are important in the context of species management, other psychometric factors add to our understanding of acceptability. We conclude that awareness about different acceptability patterns related to species management can support environmental policies on biological invasions in cities. Tailoring and implementing adequate management actions can benefit from incorporating cognitive but also affective factors of the public.Projekt DEA

Electrical Quality Assurance of the Superconducting Circuits during LHC Machine Assembly

Based on the LHC powering reference database, all-together 1750 superconducting circuits were connected in the various cryogenic transfer lines of the LHC machine. Testing the continuity, magnet polarity, and the quality of the electrical insulation were the main tasks of the Electrical Quality Assurance (ELQA) activities during the LHC machine assembly. With the assembly of the LHC now complete, the paper reviews the work flow, resources, and the qualification results including the different types of electrical non-conformities

Principles of early human development and germ cell program from conserved model systems

Human primordial germ cells (hPGCs), the precursors of sperm and eggs, originate during week 2-3 of early postimplantation development(1). Using in vitro models of hPGC induction(2-4), recent studies suggest striking mechanistic differences in specification of human and mouse PGCs(5). This may partly be due to the divergence in their pluripotency networks, and early postimplantation development(6-8). Since early human embryos are inaccessible for direct studies, we considered alternatives, including porcine embryos that, as in humans, develop as bilaminar embryonic discs. Here we show that porcine PGCs (pPGCs) originate from the posterior pre-primitive streak competent epiblast by sequential upregulation of SOX17 and BLIMP1 in response to WNT and BMP signalling. Together with human and monkey in vitro models simulating peri-gastrulation development, we show conserved principles for epiblast development for competency for PGC fate, followed by initiation of the epigenetic program(9-11), regulated by a balanced SOX17–BLIMP1 gene dosage. Our combinatorial approach using human, porcine and monkey in vivo and in vitro models, provides synthetic insights on early human development