Verbesserung und Erweiterung des in-ovo-Modells für die präklinische Bildgebungsforschung unter Verwendung embryonierter Eier der Laufvogelarten Strauß (Struthio camelus) und Emu (Dromaius novaehollandiae)

oai:www.db-thueringen.de:dbt_mods_00066629Im Forschungsdiskurs zwischen Tierschutz, Reliabilität (Verlässlichkeit) und Translation (Übertragbarkeit) auf den Menschen entstehen in der präklinischen Forschung zunehmend alternative Forschungsmodelle mit der Intention, den klassischen Tierversuch mit Säugetieren wie Mäusen und Ratten partiell oder vollständig zu ersetzen. Zwei unterschiedliche Aspekte eines solchen alternativen Tiermodells stehen im Fokus der vorliegenden Dissertation. Sie resultieren aus einem mehrjährigen, von der Deutschen Forschungsgemeinschaft geförderten Projekt (FR 2724/2; WI 5346/2) mit der Zielstellung, aus dem nuklearmedizinischen Setting heraus ein weitläufig zugängliches Bildgebungsmodell zu erarbeiten, um die Entwicklung neuer diagnostischer und therapeutischer Radiopharmaka zu fördern. Im Rahmen dieses Forschungsprojektes werden unter Verwendung klinischer Schnittbildverfahren embryonierte Eier der Laufvögel Strauß und Emu untersucht. Aufgrund der Größe der Eier können bildgebende Geräte aus der Humanmedizin verwendet werden, sodass keine Kleintier-Scanner erforderlich sind, die nur an wenigen Forschungszentren vorhanden sind. Infolge der weltweiten Verfügbarkeit sowohl der Eier als auch der klinischen Tomographen, ist das Modell örtlich unabhängig nutzbar

Attaching different kinds of proteinaceous nanospheres to a variety of fabrics using ultrasound radiation

The application of a rapid, non-destructive, cost-effective technique such as ultrasonic emulsification for the coating of different textiles was explored. The technical benefits for this research were the generation of multifunctional materials and their combinations through environmentally friendly processing technologies. We have shown for the first time that ultrasonic waves can be used to coat proteinaceous micro- and nanospheres (PM) of BSA (Bovine Serum Albumin) protein and casein on the surface of cotton and polyester (PE) fabrics. The creation and the anchoring of the microbubbles to the fabrics were performed by a one step reaction, and the process is usually stopped after 3 min. The PM of bovine serum albumin (BSA) bonded to cotton and polyester fabrics has shown stability for ~9 months. The PMs were shown to be attached more strongly to the polyester than to the cotton, and sustained stronger washing conditions on PE. The diameter of the BSA and the casein spheres on cotton was in the range of 0.8–1.0 µm, while on the PE it varied between 60 and 120 nm.This research, was carried out as part of the activities of the LIDWINE Consortium, Contract No NMP2-CT-2006-026741 LIDWINE is an IP Project of the 6th EC Progra

Hierarchically Porous Gd3+-Doped CeO2 Nanostructures for the Remarkable Enhancement of Optical and Magnetic Properties

Rare earth ion-doped CeO2 has attracted more and more attention because of its special electrical, optical, magnetic, or catalytic properties. In this paper, a facile electrochemical deposition route was reported for the direct growth of the porous Gd-doped CeO2. The formation process of Gd-doped CeO2 composites was investigated. The obtained deposits were characterized by SEM, EDS, XRD, and XPS. The porous Gd3+- doped CeO2 (10 at% Gd) displays a typical type I adsorption isotherm and yields a large specific surface area of 135 m2/g. As Gd3+ ions were doped into CeO2 lattice, the absorption spectrum of Gd3+-doped CeO2 nanocrystals exhibited a red shift compared with porous CeO2 nanocrystals and bulk CeO2, and the luminescence of Gd3+-doped CeO2 deposits was remarkably enhanced due to the presence of more oxygen vacancies. In addition, the strong magnetic properties of Gd-doped CeO2 (10 at% Gd) were observed, which may be caused by Gd3+ ions or more oxygen defects in deposits. In addition, the catalytic activity of porous Gd-doped CeO2 toward CO oxidation was studied

Releasing dye encapsulated in proteinaceous microspheres on conductive fabrics by electric current

The current paper reports on the relase properties of conductive fabrics coated with proteinaceous microspheres containing a dye. The release of the dye was achieved by passing an electric current through the fabric. The conductivity of the polyester fibers resulted from nanosilver (Ag NPs) coated on the surface of these fibers. Both types of coatings (nanosilver coating and the coating of the proteinaceous microspheres) were performed using high-intensity ultrasonic waves. Two different types of dyes, hydrophilic RBBR (Remazol Brilliant Blue R) and hydrophobic ORO (Oil Red O), were encapsulated inside the microspheres (attached to the surface of polyester) and then released by applying an electric current. The Proteinaceous Microsphere (PM)-coated conductive fabrics could be used in medicine for drug release. The encapsulated dye can be replaced with a drug that could be released from the surface of fabrics by applying a low voltage

Mesoporous iron-titania catalyst for cyclohexane oxidation

This is the first report of using ultrasound radiation for depositing a nanosized catalyst (iron oxide) into the pores of a mesoporous material (titania); the resulting catalyst is used for the oxidation of cyclohexane under mild conditions

Detection of human neutrophil elastase (HNE) on wound dressings as marker of inflammation

Chronic wound fluids have elevated concentration of human neutrophil elastase (HNE) which can be used as inflammation/infection marker. Our goal is to develop functional materials for fast diagnosis of wound inflammation/infection by using HNE as a specific marker. For that, fluorogenic peptides with a HNE-specific cleavage sequence were incorporated into traditional textile dressings, to allow real-time detection of the wound status. Two different fluorogenic approaches were studied in terms of intensity of the signal generated upon HNE addition: a fluorophore 7-amino-4-trifluormethylcoumarin (AFC) conjugated to a HNE-specific peptide and two fluorophore/quencher pairs (FAM/Dabcyl and EDANS/Dabcyl) coupled to a similar peptide as a Förster resonance energy transfer (FRET) strategy. Also, two immobilization methods were tested: sonochemistry immobilization onto a cotton bandage and glutaraldehyde (GTA)-assisted chemical crosslinking onto a polyamide dressing. The immobilized fluorogenic AFC peptide showed an intense fluorescence emission in the presence of HNE. HNE also induced an enhanced fluorescent signal with the EDANS/Dabcyl FRET peptide which showed to be a more sensitive and effective strategy than the AFC peptide. However, its chemical immobilization onto the polyamide dressing greatly decreased its detection, mainly due to the more difficult access of the enzyme to the cleavage sequence of the immobilized peptide. After optimization of the in situ immobilization, it will be possible to use these fluorescence-functionalized dressings for an effective and specific monitoring of chronic wounds by simply using a portable ultraviolet (UV) light source. We envision that the development of this point-of-care medical device for wound control will have a great impact on patients life quality and reduction of costs on health care system.This study was funded by the European project InFact-Functional materials for fast diagnosis of wound infection (FP7-NMP-2013-SME-7-grant agreement no. 604278). The work done at Centre of Biological Engineering (CEB) was also supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte 2020-Programa Operacional Regional do Norte

A Novel Breast Cancer Xenograft Model Using the Ostrich Chorioallantoic Membrane—A Proof of Concept

Simple Summary: Animal testing is an important method in medical research and the development of new drugs (pharmaceuticals). Classic animal models feature mice or rats, but whenever possible, these animals should only be used for scientific purposes when absolutely necessary. Using less-developed forms, such as embryos not capable of pain perception, is considered an approach to reduce and replace adult animal testing. The use of chicken embryos for cancer research is well-known and features the implantation of cancer cells in order to form tumors (xenografts) on embryonic membranes (CAM). The tumor can be investigated via imaging methods, for example, nuclear medical imaging. However, chicken embryos are small and, therefore, require dedicated small animal imaging systems, which are expensive and require trained personnel. Therefore, we have investigated whether large ostrich embryos also are capable of growing tumors on the CAM. The large size of ostrich embryos would allow the use of routine imaging devices used for examinations in humans. We implanted breast cancer cells on the ostrich embryo CAM and successfully observed tumor growth. We suggest that the ostrich embryo is a suitable model for xenograft tumor imaging and cancer-related pharmaceutical research. This needs to be elucidated in further studies. Abstract: The avian chorioallantoic membrane (CAM) assay has attracted scientific attention in cancer research as an alternative or complementary method for in vivo animal models. Here, we present a xenograft model based on the ostrich ( struthio camelus) CAM assay for the first time. The engraftment of 2 × 10 6 breast cancer carcinoma MDA-MB-231 cells successfully lead to tumor formation. Tumor growth monitoring was evaluated in eight fertilized eggs after xenotransplantation. Cancer cells were injected directly onto the CAM surface, close to a well-vascularized area. Histological analysis confirmed the epithelial origin of tumors. The CAM of ostrich embryos provides a large experimental surface for the xenograft, while the comparably long developmental period allows for a long experimental window for tumor growth and treatment. These advantages could make the ostrich CAM assay an attractive alternative to the well-established chick embryo model. Additionally, the large size of ostrich embryos compared to mice and rats could help overcome the limitations of small animal models. The suggested ostrich model is promising for future applications, for example, in radiopharmaceutical research, the size of the embryonal organs may compensate for the loss in image resolution caused by physical limitations in small animal positron emission tomography (PET) imaging

Effects of aluminium oxide nanoparticles on bacterial growth

Production and wide application of nanomaterials have led to nanotechnology development but their release to environment and the induction of toxic reactions, affects the natural microbial communities. Therefore, studies on the impact of nanoparticles on microorganisms and environment are required and needed. The aim of this study was to assess the impact of aluminium oxide nanoparticles on the growth of Pseudomonas putida. To compare the harmfulness of different forms of aluminium oxide, the ecotoxicity of its macro-forms was also evaluated in the study. Research showed that the exposure to nanoparticles can negatively influence microorganisms. The EC50-16h determined in this study was 0.5 mg/l, and NOEC equaled 0.19 mg/l. Nano-Al2O3 proved to be more toxic to P. putida than aluminium oxide. This indicates that the nano-form of a given substance demonstrates different properties and may constitute a far greater danger for the environment than the same substance in the large form. According to EU and US EPA criteria, nano-Al2O3 proved to be very toxic and highly toxic, respectively. Changes in bacterial communities caused by nanoparticles may affect the normal biological, chemical and nutrient cycle in the ecosystem and the effect triggered by nanomaterials in relation to other organisms is unpredictable