Filtern
Erscheinungsjahr
Dokumenttyp
- Zeitschriftenartikel (20)
- Beitrag zu einem Tagungsband (1)
- Sonstiges (1)
- Forschungsbericht (1)
Schlagworte
- ELISA (6)
- Abwasser (2)
- Carbamazepine (2)
- Ethinylestradiol (2)
- Konjugate (2)
- LC-MS/MS (2)
- Porphyrin (2)
- Sulfamethoxazole (2)
- Surface water (2)
- Therapeutische Antikörper (2)
Organisationseinheit der BAM
Gastric cancer (GC) is the 3rd deadliest cancer worldwide, due to limited treatment options and late diagnosis. Human epidermal growth factor receptor-2 (HER2) is overexpressed in similar to 20% of GC cases and anti-HER2 antibody trastuzumab in combination with conventional chemotherapy, is recognized as standard therapy for HER2-positive metastatic GC. This strategy improves GC patients' survival by 2-3 months, however its optimal results in breast cancer indicate that GC survival may be improved. A new photoimmunoconjugate was developed by conjugating a porphyrin with trastuzumab (Trast: Porph) for targeted photodynamic therapy in HER2-positive GC. Using mass spectrometry analysis, the lysine residues in the trastuzumab structure most prone for porphyrin conjugation were mapped. The in vitro data demonstrates that Trast: Porph specifically binds to HER2-positive cells, accumulates intracellularly, co-localizes with lysosomal marker LAMP1, and induces massive HER2-positive cell death upon cellular irradiation. The high selectivity and cytotoxicity of Trast: Porph based photoimmunotherapy is confirmed in vivo in comparison with trastuzumab alone, using nude mice xenografted with a HER2-positive GC cell line. In the setting of human disease, these data suggest that repetitive cycles of Trast: Porph photoimmunotherapy may be used as an improved treatment strategy in HER2-positive GC patients.
Under the auspices of the Protein Analysis Working Group (PAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a pilot study, CCQM-P216, was coordinated by the Chinese National Institute of Metrology (NIM), National Research Council of Canada (NRC) and the Bureau International des Poids et Mesures (BIPM). Eleven Metrology Institutes or Designated Institutes and the BIPM participated in the first phase of the pilot study (Part 1). The purpose of this pilot study was to develop measurement capabilities for larger proteins using a recombinant humanized IgG monoclonal antibody against Spike glycoprotein of SARS-CoV-2 (Anti-S IgG mAb) in solution. The first phase of the study was designed to employ established methods that had been previously studies by the CCQM Protein Analysis Working Group, involving the digestion of protein down to the peptide or amino acid level. The global coronavirus pandemic has also led to increased focus on antibody quantitation methods. IgG are among the immunoglobulins produced by the immune system to provide protection against SARS-CoV-2. Anti-SARS-CoV-2 IgG can therefore be detected in samples from affected patients. Antibody tests can show whether a person has been exposed to the SARS-CoV-2, and whether or not they potentially show lasting immunity to the disease. With the constant spread of the virus and the high pressure of re-opening economies, antibody testing plays a critical role in the fight against COVID-19 by helping healthcare professionals to identify individuals who have developed an immune response, either via vaccination or exposure to the virus. Many countries have launched large-scale antibody testing for COVID-19. The development of measurement standards for the antibody detection of SARS-CoV-2 is critically important to deal with the challenges of the COVID-19 pandemic. In this study, the SARS-CoV-2 monoclonal antibody is being used as a model system to build capacity in methods that can be used in antibody quantification. Amino acid reference values with corresponding expanded uncertainty of 36.10 ± 1.55 mg/kg, 38.75 ± 1.45 mg/kg, 18.46 ± 0.78 mg/kg, 16.20 ± 0.67 mg/kg and 30.61 ± 1.30 mg/kg have been established for leucine, valine, phenylalanine, isoleucine and proline, respectively. Agreement between nearly all laboratories was achieved for the amino acid analysis within 2 to 2.5 %, with one participant achieving markedly higher results due to a technical issue found in their procedure; this result was thus excluded from the reference value calculations. The relatively good agreement within a laboratory between different amino acids was not dissimilar to previous results for peptides or small proteins, indicating that factors such as hydrolysis conditions and calibration procedures could be the largest sources of variability. Peptide reference values with corresponding expanded uncertainty of 4.99 ± 0.28 mg/kg and 6.83 ± 0.65 mg/kg have been established for ALPAPIEK and GPSVFPLAPSSK, respectively. Not surprisingly due to prior knowledge from previous studies on peptide quantitation, agreement between laboratories for the peptide-based analysis was slightly poorer at 3 to 5 %, with one laboratory's result excluded for the peptide GPSVFPLAPSSK. Again, this level of agreement was not significantly poorer than that achieved in previous studies with smaller or less complex proteins. To reach the main text of this paper, click on Final Report.
Im Rahmen eines von der Kulturstiftung des Bundes und der Kulturstiftung der Länder geförderten
Projektes zum Erhalt naturkundlicher Nasssammlungen wurden 1) der Zustand der Sammlungen bewertet
(Profiling; Analyse der Vergällungsmittel), 2) über Workshops Expertenwissen in das Projekt gebracht,
3) neue archivbeständige Materialien und Managementmaßnahmen eingeführt (Borosilikat-Gläser und -
Röhrchen, Augenwatte, Tefloneinlagen, Japanpapier, archivbeständige Kleber und Papier, Etikettenaufbewahrung;
digitales Dichtemessgerät, Alcomon-Indikator, Kontrollintervalle), 4) Erhaltungsmaßnahmen
zur langfristigen Konservierung in großem Umfange durchgeführt (Messen der Alkoholkonzentration,
Umsetzen von Präparaten in geeignetere Gefäße, Wiederverschluss von Schaugläsern) und 5) Erfahrungen
und Diskussionsergebnisse zusammengestellt, nicht ohne auf Wissenslücken und wünschenswerte
Forschungsaspekte hinzuweisen. Das Projekt profitierte besonders von der Expertise aus den Materialwissenschaften
und der Papierrestaurierung. Das Museum für Naturkunde Berlin kooperierte eng mit
dem Berliner Medizinhistorischen Museum der Charité, der Zoologischen Staatssammlung München und
dem Forschungsinstitut Senckenberg in Frankfurt. Letzteres Museum führte ein eigenes, themenverwandtes
KUR-Projekt Restauration der Sammlungen 'Vergleichende Anatomie, Embryologie und Histologie'
des Naturmuseums Senckenberg durch.
Photodegradation of organic pollutants in water by immobilized porphyrins and phthalocyanines
(2016)
New methods for water treatment are required as a result from an increasing awareness in the reduction of the pollution impact in the environment. In the perspective of the photo-oxidation of organic pollutants present in water, the principal incentive for the preparation of heterogeneous photocatalysts is their easy recovery from the reaction mixture, which allows their reuse in successive runs, minimizing the loss of their original photocatalytic properties. Different types of supports can be used in the immobilization of photoactive species, such as porphyrins (Pors) and phthalocyanines (Pcs). This mini-review will consider the different methodologies for the immobilization of Pors and Pcs and their photocatalytic performance in the photodegradation of organic pollutants in water, addressing also their recycling ability in successive water treatments.
We report on the ferromagnetism of Sn1-xZnxO2 (x < 0.1) hierarchical nanostructures with various morphologies synthesized by a solvothermal route. A room temperature ferromagnetic and paramagnetic response was observed for all compositions, with a maximum in ferromagnetism for x = 0.04. The ferromagnetic behaviour was found to correlate with the presence of zinc on substitutional Sn sites and with a low oxygen vacancy concentration in the samples. The morphology of the nanostructures varied with zinc concentration. The strongest ferromagnetic response was observed in nanostructures with well-formed shapes, having nanoneedles on their surfaces. These nanoneedles consist of (110) and (101) planes, which are understood to be important in stabilizing the ferromagnetic defects. At higher zinc concentration the nanostructures become eroded and agglomerated, a phenomenon accompanied with a strong decrease in their ferromagnetic response. The observed trends are explained in the light of recent computational studies that discuss the relative stability of ferromagnetic defects on various surfaces and the role of oxygen vacancies in degrading ferromagnetism via an increase in free electron concentration.
The preparation of porphyrins and phthalocyanines covalently attached onto nanostructured magnetic supports consisting of magnetite nanoparticles coated with an amorphous silica shell is reported. The easy recovery of these heterogeneous photocatalysts, just by applying an external magnetic field, allows their reuse in multiple treatment cycles. The photocatalytic activity of the non-immobilized photosensitizers and the obtained hybrid materials was evaluated in the degradation of 17 beta-estradiol, as a model organic pollutant present in water, using batch and flow mode treatment systems, assisted by visible light radiation (4 mW cm(-2)). The flow mode system potentiated the photocatalytic capacity of these novel hybrid materials. In order to improve the process, further studies based on different photocatalyst concentration and pH conditions were performed. Reuse capacity of these materials was investigated upon three photocatalytic cycles.
The antimicrobial photodynamic approach has been demonstrated as an efficient and sustainable process for the eradication of microbial pathogens. In this work, silica-coated Magnetite nanoparticles (NPs) were used as carriers of glycosylated porphyrins and phthalocyanines. Their subsequent cationization
resulted in the production of stable antimicrobial photosensitizing materials, effective against E. coli. Suspensions of the photocatalysts in water present bimodal size distributions formed by big clusters and small NPs with hydrodynamic diameters between 8 and 38 nm. The presence of small NPs in the suspensions is related to an effective photodynamic inactivation (PDI) of E. coli cells. Glycosylation of the PS showed a positive effect on the PDI performance, which could be related to a higher accumulation of the photocatalyst over the bacterial cell membrane. In addition, these biocidal agents proved to be photostable and their photoactive performance decreased only between 23% and 28% upon 5 PDI cycles, mostly because of the loss of material between cycles, which makes them promising materials for water disinfection purposes.
During the last two decades, studies related to the occurrence and fate of emerging contaminants in the aquatic environment have received great attention from the international scientific community. The monitoring of the presence of these compounds is particularly important since they are known to induce adverse effects in aquatic environments, even at extremely low concentrations. This work aimed to apply a simple and effective methodology, such as enzyme-linked immunosorbent assay (ELISA), in the monitoring of 17a-ethinylestradiol (EE2) and 17b-estradiol (E2) (a synthetic and a natural hormone, respectively), carbamazepine (CBZ, an antiepileptic), cetirizine (CET, an antihistamine) and caffeine (CAF, a stimulant) in water matrices with differing salinity and organic matter contents. ELISA was proven to be a valid and practical tool, especially for screening purposes in contrast to traditional chromatographic techniques which are prohibitively expensive for an application on a broader base. The main originality of this work was to establish seasonal and spatial effects on the occurrence of the referred contaminants by using the effectiveness of ELISA to screen those compounds in samples with different characteristics.
This work reports both the seasonal and spatial quantification of the referred contaminants in the aquatic environment of the central region of Portugal, with concentrations ranging as follows: 5–87 ng L-1, for
E2, 2–17 ng L-1, for EE2, 10–1290 ng L-1, for CBZ, 10–190 ng L-1, for CET, and 62–6400 ng L-1, for CAF.
The main goal of the study was to evaluate the catalytic activity of two hybrid nanocatalysts consisting in Fe3O4 nanoparticles modified with either chitosan (CS) or polyethylene glycol (PEG)/ferrous oxalate (FO), and further deposited on solid substrate as thin films. X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM) were employed for the structural and morphological characterizations of the heterogeneous catalysts. The Degradation kinetic studies of two reactive azo dye (Reactive Black 5 (RB5) and Reactive Yellow 84 (RY84)) as well as Bisphenol A (BPA) solutions were carried out using Fenton-like oxidation, in the presence of different concentrations of H2O2, at initial near-neutral pH and room temperature. The results indicated that a low amount of catalytic material (0.15 g/L), deposited as thin film, was able to efficiently trigger dye degradation in solution in the presence of 6.5mmol/LH2O2 for RB5 and of only 1.6mmol/LH2O2 in the case of BPA and RY84. In the presence of complex matrices such asWWTP waters, the removal of BPAwas low (only 24% for effluent samples). Our findings recommend the studied immobilized nanocatalysts as promising economical tools for the pretreatment of wastewaters using advanced oxidation processes (AOPs).