Characterization of the sialic acid binding activity of Influenza A viruses using soluble variants of the H7 and H9 hemagglutinins

Binding of influenza viruses to target cells is mediated by the viral surface protein hemagglutinin. To determine the presence of binding sites for influenza A viruses on cells and tissues, soluble hemagglutinins of the H7 and H9 subtype were generated by connecting the hemagglutinin ectodomain to the Fc portion of human immunoglobulin G (H7Fc and H9Fc). Both chimeric proteins bound to different cells and tissues in a sialic acid-dependent manner. Pronounced differences were observed between H7Fc and H9Fc, in the binding both to different mammalian and avian cultured cells and to cryosections of the respiratory epithelium of different virus host species (turkey, chicken and pig). Binding of the soluble hemagglutinins was similar to the binding of virus particles, but showed differences in the binding pattern when compared to two sialic acid-specific plant lectins. These findings were substantiated by a comparative glycan array analysis revealing a very narrow recognition of sialoglycoconjugates by the plant lectins that does not reflect the glycan structures preferentially recognized by H7Fc and H9Fc. Thus, soluble hemagglutinins may serve as sialic acid-specific lectins and are a more reliable indicator of the presence of binding sites for influenza virus HA than the commonly used plant lectins

Ressourceneffizienz durch Digitalisierung: Potenziale für KMU des verarbeitenden Gewerbes

This article deals with the topic complex of resource efficiency and digital transformation in the manufacturing sector as well as the resulting interactions. In addition to the current state of the art and perspectives, the case study analysis carried out as part of a current study, as well as the developed method for establishing the resource efficiency potentials will be presented. The resultant potential and the digital measures are central components of this article

Defining Material Compliance—A Comprehensive Analysis

The increase in the number of environmental regulations has resulted in great challenges for corporations in the manufacturing industry, especially within the electronic and electrical and the mechanical engineering sector. To address these compliance requirements, specialized management fields such as environmental compliance, substructures and management approaches have been implemented in industry. Recently, adherence to requirements concerning the composition of products and the use of materials and substances within products has become increasingly important and is referred to as material compliance (MC). Although the topic is of increasing importance, there is no generally accepted definition for MC nor a management framework. Corporations are thus unable to systematically address MC, and compliance violations occur frequently. We derived a definition for MC based on extensive literature research, which we subsequently evaluated in a quantitative survey. Our results indicate that MC is commonly understood as the adherence to requirements concerning the composition of a product and the use of substances and materials within products. By proposing a definition for MC, we aim to introduce a common understanding, enable future research to systematically address the topic and develop a framework for the management of MC

Defining Material Compliance—A Comprehensive Analysis

The increase in the number of environmental regulations has resulted in great challenges for corporations in the manufacturing industry, especially within the electronic and electrical and the mechanical engineering sector. To address these compliance requirements, specialized management fields such as environmental compliance, substructures and management approaches have been implemented in industry. Recently, adherence to requirements concerning the composition of products and the use of materials and substances within products has become increasingly important and is referred to as material compliance (MC). Although the topic is of increasing importance, there is no generally accepted definition for MC nor a management framework. Corporations are thus unable to systematically address MC, and compliance violations occur frequently. We derived a definition for MC based on extensive literature research, which we subsequently evaluated in a quantitative survey. Our results indicate that MC is commonly understood as the adherence to requirements concerning the composition of a product and the use of substances and materials within products. By proposing a definition for MC, we aim to introduce a common understanding, enable future research to systematically address the topic and develop a framework for the management of MC

Comparison of sliding window and field-in-field techniques for tangential whole breast irradiation using the Halcyon and Synergy Agility systems

Background To implement a tangential treatment technique for whole breast irradiation using the Varian Halcyon and to compare it with Elekta Synergy Agility plans. Methods For 20 patients two comparable treatment plans with respect to dose coverage and normal tissue sparing were generated. Tangential field-in-field treatment plans (Pinnacle/Synergy) were replanned using the sliding window technique (Eclipse/Halcyon). Plan specific QA was performed using the portal Dosimetry and the ArcCHECK phantom. Imaging and treatment dose were evaluated for treatment delivery on both systems using a modified CIRS Phantom. Results The mean number of monitor units for a fraction dose of 2.67 Gy was 515 MUs and 260 MUs for Halcyon and Synergy Agility plans, respectively. The homogeneity index and dose coverage were similar for both treatment units. The plan specific QA showed good agreement between measured and calculated plans. All Halcyon plans passed portal dosimetry QA (3%/2 mm) with 100% points passing and ArcCheck QA (3%/2 mm) with 99.5%. Measurement of the cumulated treatment and imaging dose with the CIRS phantom resulted in lower dose to the contralateral breast for the Halcyon plans. Conclusions For the Varian Halcyon a plan quality similar to the Elekta Synergy device was achieved. For the Halcyon plans the dose contribution from the treatment fields to the contralateral breast was even lower due to less interleaf transmission of the Halcyon MLC and a lower contribution of scattered dose from the collimator system

Binding to MDCKII cells after neuraminidase pretreatment.

<p>Cells were incubated with 200<i>Clostridium perfringens</i> for 1 h at 37°C. After enzyme treatment, cells were fixed and binding tests and lectin staining were performed.</p

Western blot of soluble hemagglutinins H7Fc and H9Fc.

<p>Soluble hemagglutinins were prepared from the supernatant of transfected HEK 293T cells, after separation by SDS PAGE under reducing conditions. Proteins were detected using peroxidase conjugated anti-human IgG directed against the Fc-tag.</p

Binding of soluble HAs to tissue sections.

<p>Sections of chicken and turkey were incubated with 400 pmol soluble HA. Porcine respiratory epithelium was incubated with 600 pmol soluble HAs to obtain a visible staining. Bound HAs were detected using anti-human IgG-FITC (green). To assess the quality of the epithelium and to visualize cell boundaries, sections were counterstained with phalloidin-rhodamin (red). Nuclei were stained with DAPI. The lower panels show lectin staining of the tissue sections with MAAII-Biotin (red staining by Strepatavidin-Cy3) and FITC-conjugated SNA (green).</p

Immunofluorescence binding test of soluble HAs on mammalian and avian cells.

<p>Cells were incubated with 100 pmol of the respective soluble HA or the control FcATG. Soluble HAs were detected using anti-human-FITC antibody and nuclei were stained with DAPI. In addition, lectin staining was performed to display the presence of α2,3 (Biotin conjugated MAAII and Streptavidin-FITC) and α2,6 linked sialic acids (FITC conjugated SNA).</p