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Synthetic polymers typically show dispersity in molecular weight and potentially in chemical composition. For the analysis of the chemical-composition distribution (CCD) gradient liquid chromatography may be used. The CCD obtained using this method is often convoluted with an underlying molecular-weight distribution (MWD). In this paper we demonstrate that the influence of the MWD can be reduced using very steep gradients and that such gradients are best realized utilizing recycling gradient liquid chromatography (LC↻LC). This method allows for a more-accurate determination of the CCD and the assessment of (approximate) critical conditions (if these exist), even when high-molecular-weight standards of narrow dispersity are not readily available. The performance and usefulness of the approach is demonstrated for several polystyrene standards, and for the separation of statistical copolymers consisting of styrene/methyl methacrylate and methyl methacrylate/butyl methacrylate. For the latter case, approximate critical compositions of the copolymers were calculated from the critical compositions of two homopolymers and one copolymer of known chemical composition, allowing for a determination of the CCD of unknown samples. Using this approach it is shown that the copolymers elute significantly closer to the predicted critical compositions after recycling of the gradient. This is most clear for the lowest-molecular-weight copolymer (Mw = 4.2 kDa), for which the difference between measured and predicted elution composition decreases from 7.9% without recycling to 1.4% after recycling.

This article treats the topic of consumer waste by beginning with a contemporary story that illustrates the reality and complex dynamics of throwaway culture. Noting the dynamic quality of waste, it offers a brief review of the development of throwaway society. Beginning in a preindustrial world in which the battle against “moth and rust” required habits of reuse and repair, or what cultural historian Susan Strasser refers to as bricolage, it then traces changes in “natural” and “temporal” imaginaries, as well as economic and technological factors, that rendered obsolete the cultural skills and imaginative capacities of bricolage. Having argued that forgetting and loss of imagination are key to waste-making, it offers two Christian responses that schools and faith communities might practice: “material anamnesis” and “redemptive vision.”

Global ecological crisis calls for humanity's “ecological conversion,” as well as deconversion from consumerism as a faith system. Conversion involves the imagination, which suggests an important r...

Although microplastics are ubiquitous in today’s natural environments, our understanding of the materials, quantities, and particle sizes involved remains limited. The recovery of microplastics from different types of environmental matrices requires standardized matrix digestion protocols that allow inter-laboratory comparisons and that have no effect on the polymers themselves. A number of commonly used digestion methods rely on oxidation with concentrated hydrogen peroxide solutions to remove organic matter from the matrix. However, this can alter the nature of polymers through hydrolysis and often does not lead to a complete matrix removal. We have therefore investigated the use of two altered matrix digestion protocols, an acidic (Fenton) protocol and a new alkaline (Basic Piranha) protocol, focusing mainly on the effect on biodegradable polymers (polylactide, polybutylene adipate terephthalate, polybutylene succinate) and polymers with known degradation pathways via hydrolysis (thermoplastic polyurethanes, polyamide). Comparing the initial surface textures, chemical compositions, and particle size distributions with those obtained after digestion revealed that the Fenton protocol left most of the polymers unchanged. The ferrous residue that remains following Fenton digestion had no effect on either the polymer composition or the particle size distribution, but could disturb further analytics (e.g. Raman microscopy due to auto-fluorescence). While increasing the chance of complete matrix removal, the more powerful Basic Piranha protocol is also more likely to affect the polymer properties: Polylactide polymers in particular showed signs of degradation under alkaline digestion (reduced polylactide content, holes in the polymer matrix), indicating the unsuitability of the Basic Piranha protocol in this specific case. Polyamide, however, remained stable during the Basic Piranha treatment, and the surface chemistry, the particle size as well as the molar mass distribution of the investigated thermoplastic polyurethanes were also not affected. Hence, this protocol offers a powerful alternative for microplastic analysis with focus on particle size in more complex environmental matrices (e.g. removal of cellulose in soil), while avoiding ferrous Fenton residue. Unexpectedly, also tire rubber, a frequent target analyte in microplastic monitoring, was found to be susceptible to artefact structures by both oxidation protocols. In summary, controls for the specific combination of polymer and sample preparation protocol are highly recommended to select the most fitting protocol. Here selected suitable combinations are reported.

Many materials used in a wide range of fields consist of polymers that feature great structural complexity. One particularly suitable technique for characterising these complex polymers, that often feature correlated distributions in e.g. microstructure, chemical composition, or molecular weight, is comprehensive two-dimensional liquid chromatography (LC × LC). For example, using a combination of reversed-phase LC and size-exclusion chromatography (RPLC × SEC). Efficient and sensitive LC × LC often requires focusing of the analytes between the two stages. For the analysis of large-molecule analytes, such as synthetic polymers, thermal modulation (or cold trapping) may be feasible. This approach is studied for the analysis of a styrene/butadiene “star” block copolymer. Trapping efficiency is evaluated qualitatively by monitoring the effluent of the trap with an evaporative light-scattering detector and quantitatively by determining the recovery of polystyrene standards from RPLC × SEC experiments. The recovery was dependant on the molecular weight and the temperatures of the first-dimension column and of the trap, and ranged from 46% for a molecular weight of 2.78 kDa to 86% (or up to 94.5% using an optimized set-up) for a molecular weight of 29.15 kDa, all at a first-dimension-column temperature of 80 °C and a trap temperature of 5 °C. Additionally a strategy to reduce the pressure pulse from the modulation has been developed, bringing it down from several tens of bars to only a few bar.

This essay describes an introductory theology course that appears to support ecological conversion. Ecological conversion is a term from Catholic Social Teaching popularized by Pope Francis in Laudato Si’; it indicates a transformation that results in ecological spirituality. The author, a Protestant theology professor at a Catholic university, makes a brief case for ecological conversion in the university and offers four reasons for the course’s impact: 1) a case study on consumerism, 2) cultivation of attentiveness, 3) a transformative pedagogy, and 4) a holistic approach. The author describes the units of the course, which are adapted from Richard Osmer’s practical theological reflection cycle, operationalized as a transformative pedagogy. The author shows how the course units track with a conversion sequence outlined by Lewis Rambo while calling for student agency and appropriation, thus supporting ecological conversion. The author details teaching practice and student engagement.

Copolymer products that result from grafting acrylic acid and other hydrophilicmonomers onto polysaccharides have recently gained significant interest in researchand industry. Originating from renewable sources, these biodegradable, low toxicity,and polar copolymer products exhibit potential to replace polymers from fossil sourcesin several applications and industries. The methods usually employed to character-ize these copolymers are, however, quite limited, especially for the measurement ofbulk properties. With more sophisticated applications, for example, in pharmaceu-tics requiring a more detailed analysis of the chemical structure, we describe a newapproach for this kind of complex polymers. Our approach utilizes chromatographyin combination with several detection methods to separate and characterize reactionproducts of the copolymerization of acrylic acid and chemically hydrolyzed starch.These samples consisted of a mixture of homopolymer poly (acrylic acid), homopoly-mer hydrolyzed starch, and – in a lower amount – the formed copolymers. Several chro-matographic methods exist that are capable of characterizing either poly (acrylic acid)or hydrolyzed starch. In contrast, our approach offers simultaneous characterization ofboth polymers. The combination of LC and UV/RI offered insight into the compositionand copolymer content of the samples. Size exclusion chromatography experimentsrevealed the molar mass distribution of homopolymers and copolymers. FTIR inves-tigations confirmed the formation of copolymers while ESI-MS gave more details onthe end groups of hydrolyzed starches and poly (acrylic acids). Evidence of copolymerstructures was obtained through NMR measurements. Finally, two-dimensional chro-matography led to the separation of the copolymers from both homopolymers as wellas the additional separation of sodium clusters. The methods described in this work area powerful toolset to characterize copolymerization products of hydrolyzed starch andpoly(acrylic acid). Together, our approach successfully correlates the physicochemicalproperties of such complex mixtures with their actual composition.

With the ever-increasing complexity of polymeric structures obtained via contemporary synthetic strategies, their precision analysis is a challenging task. Thus, powerful analytical techniques must be explored to allow for an in-depth characterization of complex polymers, yielding chemical information at a sensitivity beyond that of commonly applied analysis methods such as conventional size exclusion chromatography (SEC) and NMR spectroscopy. Here, a tutorial overview on the hyphenation of SEC to electrospray ionization mass spectrometry (ESI-MS) is presented, highlighting the resulting benefits in the context of polymer characterization. First, the capability of obtaining structural information of polymers as well as verifying polymer analogous transformations via SEC-ESI-MS is outlined. Importantly, the wide applicability of SEC-ESI-MS is highlighted, e.g. by its use for the determination of radical polymerization rate coefficients, the detailed investigation of radical photoinitiations systems and the examination of absolute molecular weight distributions of polymers. The current tutorial review thus aims to demonstrate the power of SEC-ESI-MS for the characterization of complex polymers and to underline the high potential it has to become a powerful and popular analytical technique in polymer chemistry.

We pioneer a versatile surface modification strategy based on mussel-inspired oxidative catecholamine polymerization for the design of nitroxide-containing thin polymer films. A 3,4-dihydroxy-l-phenylalanine (l-DOPA) monomer equipped with a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-derived oxidation-labile hydroxylamine functional group is employed as a universal coating agent to generate polymer scaffolds with persistent radical character. Various types of materials including silicon, titanium, ceramic alumina, and inert poly(tetrafluoroethylene) (PTFE) were successfully coated with poly(DOPA-TEMPO) thin films in a one-step dip-coating procedure under aerobic, slightly alkaline (pH 8.5) conditions. Steadily growing polymer films (∼1.1 nm h–1) were monitored by ellipsometry, and their thicknesses were critically compared with those obtained from atomic force microscopic cross-sectional profiles. The heterogeneous composition of surface-adherent nitroxide scaffolds examined by X-ray photoelectron spectr...

We introduce the preparation and ring-opening polymerization of a nitroxide containing carbonate monomer. Using 1,8-diazabicyclo undec-7-ene (DBU) and a thiourea as the catalyst system, we demonstrate that the free radical moiety of the monomer has no influence on the ring-opening copolymerization with D/L-lactide in a wide range of compositions between 10% and 80% of the nitroxide monomer, which can be readily controlled by the comonomer composition in the polymerization mixture. The copolymers exhibit narrow and monomodal mass distributions with number average molar masses between 6000 g·mol −1 to 7000 g·mol −1 and low dispersities below 1.1. The free radical functionality is retained during the polymerization as demonstrated by electron spin resonance (EPR) spectroscopy. High-resolution mass spectrometry coupled to size exclusion chromatography allowed an in-depth analysis of the copolymers showing well-defined linear polymer chains with excellent endgroup fidelity. Furthermore, the molar mass of the polymers was controlled by the monomer to initiator ratio which led to copolymers of up to 19 500 g·mol −1 .

We introduce the high-resolution electrospray ionization mass spectrometric (ESI MS) structural elucidation of polymerized 3,4-dihydroxy-L-phenylalanine (L-DOPA) carrying 1-methoxy-2,2,6,6-tetramethylpiperidin-4-amide groups in the side chain. Critically, our powerful ESI MS platform unambiguously revealed the structurally diverse character of this multifunctional bio-adhesive polymer system.

Small Ca(2+) binding adaptor proteins of the EF hand family play important roles in neuronal and immune cell Ca(2+) signaling. Swiprosin-1/EFhd2 (EFhd2) and Swiprosin-2/EFhd1 (EFhd1) are conserved and very homologous Ca(2+) binding adaptor proteins of the EF hand family, with possibly redundant functions. In particular, EFhd2 has been proposed to be involved in B cell signaling and neuropathological disorders. Little is known thus far about the expression of EFhd2 on the single cell level in tissue sections or blood cells. Here we describe the generation of four specific anti-EFhd2 monoclonal antibodies. These recognize murine and human EFhd2, but not murine EFhd1, and their binding site maps to a region in the N-terminal part of EFhd2, where EFhd2 and EFhd1 differ most. Moreover, to detect EFhd1 specifically, we also generated anti-EFhd1 polyclonal antibodies, making use of a singular peptide of the N-terminal part of the protein. Using anti-EFhd2 MAb, we reveal two EFhd2 pools in B cells, one at the membrane and one cytoplasmic pool. Staining of human peripheral blood mononuclear cells shows EFhd2 expression in B cells but a ∼5 fold higher expression in monocytes. Taken together, EFhd2 monoclonal antibodies will be valuable to assess the real subcellular localization and expression level of EFhd2 in healthy and diseased primary cells and tissues.

Three different parasites of the phylum Parabasala (Tritrichomonas foetus, Trichomitus rotunda and Tetratrichomonas buttreyi) have been described in pigs. In a previous study (Mostegl et al., 2011) approximately 47% of 91 paraffin wax-embedded intestinal samples of pigs which were Trichomonas-positive by in situ hybridization using a probe with a broad reactivity spectrum contained other species than T. foetus. Out of these, intestinal trichomonads from three pigs (pigs 1–3) were further analyzed by gene sequencing of a part of the 18S ribosomal RNA (rRNA) gene using primer walking. Subsequently, the partial sequences achieved by the different primer pairs were combined to a sequence of about 1000bp for each trichomonad. In all three pigs unique sequences were acquired which showed only moderate similarities to sequences available in the GenBank. Alignments and the BLAST analysis showed a high degree of homology between sequences of trichomonads from pig 1 and pig 3 with only 1% difference. These sequences were found to be 92% similar to Hypotrichomonas acosta, a trichomonad isolated from squamate reptiles. The trichomonad sequence detected in the intestine of pig 2 showed about 10% nucleotide differences compared to pigs 1 and 3. This sequence was 97% similar to two Trichomitus batrachorum (a frog symbiont) sequences. A phylogenetic analysis using the neighbor-joining and maximum likelihood methods supported the data of the BLAST analysis. These results suggest the presence of at least two as yet undescribed trichomonad species in the intestinal contents of pigs.

The application of copper-catalyzed azide/alkyne cycloaddition to monomers containing a ferrocene unit leads to polyferrocenes with ferrocene in the backbone. Catalyst performance and kinetic studies of a model system comprising 1,1'-bis(azidoethyl)ferrocene and propargyl ether revealed the usage of CuI and DBU as the catalyst in DMF at 50 °C as efficient reaction conditions for the synthesis. The resulting polymers display molecular weight-averages up to M n = 10 000 and M w = 33 000. The polyaddition of monomers both containing ferrocene units led to polyferrocenes with M n between 4 000 and 11 000 ( M w up to 78 000). The present study thus provides a pathway to polyferrocenes based on modular ligation chemistry.

Compartmentalization of the BCR in membrane rafts is important for its signaling capacity. Swiprosin-1/EFhd2 (Swip-1) is an EF-hand and coiled-coil–containing adaptor protein with predicted Src homology 3 (SH3) binding sites that we identified in membrane rafts. We showed previously that Swip-1 amplifies BCR-induced apoptosis; however, the mechanism of this amplification was unknown. To address this question, we overexpressed Swip-1 and found that Swip-1 amplified the BCR-induced calcium flux in WEHI231, B62.1, and Bal17 cells. Conversely, the BCR-elicited calcium flux was strongly attenuated in Swip-1–silenced WEHI231 cells, and this was due to a decreased calcium mobilization from intracellular stores. Complementation of Swip-1 expression in Swip-1–silenced WEHI231 cells restored the BCR-induced calcium flux and enhanced spleen tyrosine kinase (Syk) tyrosine phosphorylation and activity as well as SLP65/BLNK/BASH and phospholipase C γ2 (PLCγ2) tyrosine phosphorylation. Furthermore, Swip-1 induced the constitutive association of the BCR itself, Syk, and PLCγ2 with membrane rafts. Concomitantly, Swip-1 stabilized the association of BCR with tyrosine-phosphorylated proteins, specifically Syk and PLCγ2, and enhanced the constitutive interaction of Syk and PLCγ2 with Lyn. Interestingly, Swip-1 bound to the rSH3 domains of the Src kinases Lyn and Fgr, as well as to that of PLCγ. Deletion of the predicted SH3-binding region in Swip-1 diminished its association and that of Syk and PLCγ2 with membrane rafts, reduced its interaction with the SH3 domain of PLCγ, and diminished the BCR-induced calcium flux. Hence, Swip-1 provides a membrane scaffold that is required for the Syk-, SLP-65–, and PLCγ2-dependent BCR-induced calcium flux.

A platform technology for the creation of spatially resolved surfaces encoded with a monolayer consisting of different metal complexes was developed. The concept entails the light-triggered activation of a self- assembled monolayer (SAM) of UV-labile anchors, that is, phenacylsulfides, and the subsequent cycloaddition of selected diene-functionalized metal complexes at defined areas on the surface. The synthesis and characterization of the metal complexes for the UV-light assisted anchoring on the surface and a detailed study of a short-chain oligomer model system in solution confirm the high efficiency of the photoreaction. The hybrid materials obtained by this concept can potentially be utilized for the design of highly valuable catalytic or (opto-)electronic devices.

Lipid rafts serve as platforms for BCR signal transduction. To better define the molecular basis of these membrane microdomains, we used two-dimensional gel electrophoresis and mass spectrometry to characterize lipid raft proteins from mature as well as immature B cell lines. Of 51 specific raft proteins, we identified a total of 18 proteins by peptide mass fingerprinting. Among them, we found vacuolar ATPase subunits α-1 and β-2, vimentin, γ-actin, mitofilin, and prohibitin. None of these has previously been reported in lipid rafts of B cells. The differential raft association of three proteins, including a novel potential signaling molecule designated swiprosin-1, correlated with the stage-specific sensitivity of B cells to BCR-induced apoptosis. In addition, MHC class II molecules were detected in lipid rafts of mature, but not immature B cells. This intriguing finding points to a role for lipid rafts in regulating Ag presentation during B cell maturation. Finally, a fraction of the BCR in the B cell line CH27 was constitutively present in lipid rafts. Surprisingly, this fraction was neither expressed at the cell surface nor fully O-glycosylated. Thus, we conclude that partitioning the BCR into lipid rafts occurs in the endoplasmic reticulum/cis-Golgi compartment and may represent a control mechanism for surface transport.

Patients sustaining facial fractures are at risk for accompanying traumatic intracranial hematomas, which are a major cause of morbidity and mortality. Prompt recognition is crucial in improving patient survival and recovery. This study examined which simple clinical signs identify facial fracture patients at risk for intracranial hemorrhage before the performance of computed tomography. Retrospective study of 2,195 patients with facial fractures during a period of 7 years. By means of univariate and multivariate analysis clinical features potentially predictive for (a) intracranial hemorrhage and (b) surgery for intracranial hemorrhage were identified. Critical care units of anesthesiology and neurology, general traumatology, and oral and maxillofacial surgery in a level I trauma university hospital. Seizures (OR 22.1) and vomiting/nausea (OR 20.2) were the strongest independent predictors of intracranial bleeding in facial fracture patients. For intracranial hemorrhages requiring surgical intervention closed head injuries (OR 9.75) and cranial vault fractures (OR 5.0) were the most significant risk factors. However, among those patients without vomiting/nausea and without seizures and without closed head injury (n=1,628), 20 patients (1.2%) suffered intracranial hemorrhage, and six (0.37%) of them required surgical intervention. Simple clinical symptoms, such as seizures, vomiting/nausea, history of a closed head injury or cranial vault fractures are strong predictors for intracranial hemorrhage in facial fracture patients. The early consideration of such important indicators allows us to detect patients at elevated risk of an intracranial hematoma requiring surgical intervention.

Grötsch et al. find that the AP-1 transcription factor Fra-1 limits the generation of antibody-producing plasma cells. Absence of Fra1 in B cells results in abnormally high numbers of plasma cells and increased antibody responses after vaccination., The cornerstone of humoral immunity is the differentiation of B cells into antibody-secreting plasma cells. This process is tightly controlled by a regulatory gene network centered on the transcriptional repressor B lymphocyte–induced maturation protein 1 (Blimp1). Proliferation of activated B cells is required to foster Blimp1 expression but needs to be terminated to avoid overshooting immune reactions. Activator protein 1 (AP-1) transcription factors become quickly up-regulated upon B cell activation. We demonstrate that Fra1, a Fos member of AP-1, enhances activation-induced cell death upon induction in activated B cells. Moreover, mice with B cell–specific deletion of Fra1 show enhanced plasma cell differentiation and exacerbated antibody responses. In contrast, transgenic overexpression of Fra1 blocks plasma cell differentiation and immunoglobulin production, which cannot be rescued by Bcl2. On the molecular level, Fra1 represses Blimp1 expression and interferes with binding of the activating AP-1 member c-Fos to the Blimp1 promoter. Conversely, overexpression of c-Fos in Fra1 transgenic B cells releases Blimp1 repression. As Fra1 lacks transcriptional transactivation domains, we propose that Fra1 inhibits Blimp1 expression and negatively controls plasma cell differentiation through binding to the Blimp1 promoter. In summary, we demonstrate that Fra1 negatively controls plasma cell differentiation by repressing Blimp1 expression.

One component of host defense at mucosal surfaces appears to be epithelium-derived antimicrobial peptides. Molecules of the defensin and cathelicidin families have been studied in several species, including human and mouse. We describe in this report the identification and characterization of rhesus monkey homologues of human mucosal antimicrobial peptides. Using reverse transcriptase PCR methodology, we cloned the cDNAs of rhesus monkey β-defensin 1 and 2 (rhBD-1 and rhBD-2) and rhesus monkey LL-37/CAP-18 (rhLL-37/rhCAP-18). The predicted amino acid sequences showed a high degree of homology to the human molecules. The expression of the monkey antimicrobial peptides was analyzed using immunohistochemistry with three polyclonal antibodies to the human molecules. As in humans, rhesus monkey antimicrobial peptides are expressed in epithelia of various organs. The present study demonstrates that β-defensins and cathelicidins of rhesus monkeys are close homologues to the human molecules and indicate that nonhuman primates represent valid model organisms to study innate immune functions.

Samples were collected from 203 wild boars (Sus scrofa) hunted in Baden-Wurtemburg, Germany from November-January 2008 and 2009. Samples from the lung and tonsil were analyzed by quantitative polymerase chain reaction (qPCR) for porcine reproductive and respiratory syndrome virus (PRRSV) type 1 (European type) and type 2 (American type). A qPCR to detect porcine circovirus type 2 (PCV2)-specific genome was performed on tissue homogenates including lung, tonsils, and inguinal lymph nodes. Serum samples were tested for antibodies against PRRSV and PCV2 by enzyme-linked immunosorbent assay (ELISA). No PRRSV was detected in any of the 203 samples and one sample had detectable antibodies against PRRSV. We detected PCV2 in organ materials from 103 wild boars with a prevalence of 50.7%. The number of wild boars positive for PCV2 by PCR varied according to the population density of wild boars among woodlands. More positive samples were detected in woodlands with a high density of wild boars. We found no correlation between the number of PCV2-positive wild boars and the density of domestic pigs in the surrounding area. The number of wild boars positive for antibodies against PCV2 by the INGEZIM Circovirus IgG/IgM test kit was low (53 sera positive for IgG- and three sera positive for IgM-antibodies) in comparison to the higher positive results from the INGEZIM CIRCO IgG test kit (102 positive and 12 inconclusive results).

The B cell receptor (BCR)-elicited calcium flux results in activation of mature B cells. We have recently shown that the adaptor protein Swiprosin-1/EFhd2 (EFhd2) amplifies the BCR-induced calcium flux in B cell lines. EFhd2 is a calcium binding adaptor protein with two predicted EF-hands. Here we asked whether these domains are functional and control its function. Using a blot-overlay assay with radioactive calcium we show that both EF-hands of EFhd2 have an intrinsic capacity to bind calcium. Equilibrium centrifugation confirmed that EFhd2 binds 2 calcium ions, with an apparent K d of 110 μM. Point mutations revealed that the conserved residues E116 and E152, which reside in the canonical calcium binding loop in EF-hands 1 and 2, are essential for calcium binding by EFhd2. These mutations as well as deletion of the EF-hands, in particular EF-hand 1, abolished the ability of EFhd2 to restore BCR-induced calcium signaling in EFhd2-deficient WEHI231 cells. N-terminal deletions, but not C-terminal deletions, acted similarly. Thus, the N-terminal part of EFhd2 as well as calcium binding to its EF-hands control the intracellular calcium concentration in response to BCR stimulation in WEHI231 cells. Hence, EFhd2 regulates the BCR-elicited calcium flux through a calcium-dependent positive feedback mechanism in WEHI231 cells.

In the present retrospective study, serum samples from a total of 253 pigs of different age groups from 83 farms collected in the year 2008 were included.The sera were analysed for the presence of torque teno virus (TTV) genogroups 1 and 2. Furthermore, the correlation between TTV and PCV-2 was investigated. 62.1% of the pigs were positive for TTV1 and/or TTV2 by PCR. 21.7% of the samples were positive for TTV1 and TTV2, 16.2% only for TTV1 and 23.3% only for TTV2. In 80.7% of the investigated farms at least one animal was TTV positive. In the growing and fattening period significantly more pigs were positive for TTV than in other age classes. A positive association was found between TTV1 and IgM against PCV-2, between TTV2 and PCV-2 results by in situ hybridisation (ISH) as well as TTV1 and TTV2 and PCV-2 results by qPCR. A significant correlation could also be seen between the diagnosis,porcine respiratory disease complex (PRDC)" and the detection of TTV, whereas there was none to the diagnosis "porcine dermatitis and nephropathy syndrome (PDNS)". In the present study, TTV was detected in Austria for the first time.

A total of 1026 serum samples from 388 pigs from three Bavarian rearing farms in the region of Swabia were investigated in the course of investigations into the development of antibodies against Influenza A virus subtypes H1N1, H1N2 and H3N2 by haemagglutination inhibition test during the period from November 2002 to February 2004. There were no signs of respiratory disease during this period. The antibody titres decreased steadily in this period which corresponds to the kinetics of maternally-derived antibodies. Therefore the antibodies reflect the situation of influenza in the farms of origin from which the piglets were purchased. These farms were located in Bavaria and Baden-Wuerttemberg. There was a high activity of H1N1 influenza A viruses in this region whereas the antibody profiles against H1N2 and H3N2 varied between the different farms, which can be attributed to past vaccinations and infections. Thus there was a uniform immunological situation within the regions against H1N1 whereas that against H1N2 and H3N2 differed. The analysis of the antibody profiles allows conclusions to be drawn about the epidemiological situation and means of immunoprophylaxis.

The aim of the present study was to investigate the occurrence of mycotoxins in commercial dog food, as a basis to estimate the risk of adverse effects. Seventy-six dry dog food samples from 27 producers were purchased from retail shops, supermarkets, and specialized pet food shops in Vienna, Austria. The frequency and levels of deoxynivalenol (DON), zearalenone (ZEA), fumonisins (FUM), ochratoxin A (OTA). and aflatoxins (AF) in dry dog food were determined. Mycotoxin analysis were performed by commercial enzyme-linked immunosorbent assay (ELISA) test kits. Confirmatory analyses were done for DON, ZEA, and FUM by high performance liquid chromatography (HPLC) after extract clean-up with immunoaffinity columns. The correlations between ELISA and HPLC results for DON and ZEA were acceptable and indicated that ELISA could be a simple, low cost, and sensitive screening tool for mycotoxins detection, contributing to quality and safety of pet food. DON was the mycotoxin most frequently found (83% positives; median 308 µg/kg, maximum 1,390 µg/kg). ZEA (47% positives, median 51 µg/kg and maximum 298 µg/kg) and FUM (42% positives, median 122 µg/kg and maximum 568 µg/kg) were also frequently detected in dog food. OTA was less frequently found (5%, median 3.6 µg/kg, maximum 4.7 µg/kg. AF were not detected (0.5 µg/kg) in any sample. The results show that dry dog food marketed in Vienna are frequently contaminated with mycotoxins (DONZEAFUMOTA) in low concentrations, but do not contain AF. The high frequency of Fusarium toxins DON, ZEA, and FUM indicates the need for intensive control measures to prevent mycotoxins in dog foods. The mycotoxin levels found in dry dog food are considered as safe in aspects of acute mycotoxicoses. However, repeated and long-time exposure of dogs to low levels of mycotoxins may pose a health risk.

Polymers with palladium ligating moieties in the lateral chain were synthesized via consecutive CuAAC ligation. An in-depth catalyst screening was performed to optimize the reaction conditions. The obtained polymers, quantitatively loaded with palladium complexes, feature high molar masses of up to Mn = 30 000 g mol−1. The complex formation is underpinned by model complex studies. 2,6-Bis(1-(p-tolyl)-1H-1,2,3-triazol-4-yl)pyridine was used as the model ligand. Reaction of the ligand with [Pd(cod)Cl2] resulted in the corresponding palladium model complex.

AP-1 transcription factors are immediate early genes that sense changes in the cellular environment to control differentiation, proliferation and apoptosis. Their functions in B cells are poorly described and were only suggested by the pro-apoptotic role of JunB. Fra-1(FosL1), an interaction partner of JunB, has been firstly described in activated B cells. Here, we confirm that Fra-1 becomes up-regulated in activated murine primary B cells that prompted us to analyze B cell development and humoral immune responses following Fra-1 gain and loss of function in vivo. Mice over-expressing Fra-1 that displayed a reduced B2 B cell compartment failed to mount any IgG response and did not form germinal centers. Bone marrow transfer in mice lacking B cells demonstrated that these phenotypes were B cell autonomous. B cell-specific Fra-1 deficient mice developed enhanced secondary responses, further reinforcing a cell autonomous key role for Fra-1 in B cell function. In vitro experiments showed that sorted fra-1tg B2 cells that express all relevant genes required for plasma cell differentiation and class switching were unable to class-switch, do not proliferate and die after activation. Thus, we identified Fra-1 as negative regulator of IgG production and class switch that functions independently of chromatin remodeling and class switch gene expression. Our work therefore suggests that Fra-1 acts as a negative regulator of B2 B cell proliferation, which is required for Ig class switch.

Polystyrene based copolymers with palladium-ligating side groups were obtained by RAFT polymerization of chloromethyl styrene and styrene, subsequent azide transformation and quantitative copper-mediated 1,3-dipolar cycloaddition of ethynyl pyridine. Variable copolymer compositions were synthesized ranging from 10% to 50% with respect to the fraction of the palladium-ligating comonomer. The successful loading of the polymers with PdCl2 employing [Pd(COD)Cl2] (COD = 1,5-cyclooctadiene) as the metal source was confirmed by nuclear magnetic resonance spectroscopy (NMR) and elemental analysis. Absolute molecular weights of the Pd-containing polymers ranging from Mw = 16 000 g mol−1 to 20 000 g mol−1 were determined by employing static light scattering (SLS). In order to fully clarify the incorporation of palladium into the polymers, a PdCl2 complex of a chelating N donor ligand featuring the characteristic heterocyclic donor functions used to incorporate PdCl2 in the polymer was synthesized and characterized by single crystal X-ray diffraction and NMR analysis.