Oxidation of tertiary amine-derivatized surfaces to control protein adhesion

Selective oxidation of omega-tertiary amine self-assembled thiol monolayers to tertiary amine N-oxides is shown to transform the adhesion of model proteins lysozyme and fibrinogen upon them. Efficient preparation of both secondary and tertiary linker amides as judged by X-ray photoelectron spectroscopy (XPS) and water droplet contact angle was achieved with an improved amide bond formation on gold quartz crystal microbalance (QCM) sensors using 2-(1H-7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyl hexafluorophosphate methanaminium uronium (HATU). Oxidation with hydrogen peroxide was similarly assessed, and adhesion of lysozyme and fibrinogen from phosphate buffered saline was then assayed by QCM and imaged by AFM. Tertiary amine-functionalized sensors adsorbed multilayers of aggregated lysozyme, whereas tertiary amine N-oxides and triethylene glycol-terminated monolayers are consistent with small protein aggregates. The surface containing a dimethylamine N-oxide headgroup and ethyl secondary amide linker showed the largest difference in adsorption of both proteins. Oxidation of tertiary amine decorated surfaces therefore holds the potential for selective deposition of proteins and cells through masking and other patterning techniques

Preventive antibiotic treatment of calves: emergence of dysbiosis causing propagation of obese state-associated and mobile multidrug resistance-carrying bacteria

In agriculture, antibiotics are used for the treatment and prevention of livestock disease. Antibiotics perturb the bacterial gut composition but the extent of these changes and potential consequences for animal and human health is still debated. Six calves were housed in a controlled environment. Three animals received an injection of the antibiotic florfenicol (Nuflor), and three received no treatment. Faecal samples were collected at 0, 3 and 7 days, and bacterial communities were profiled to assess the impact of a therapy on the gut microbiota. Phylogenetic analysis (16S‐rDNA) established that at day 7, antibiotic‐treated microbiota showed a 10‐fold increase in facultative anaerobic Escherichia spp, a signature of imbalanced microbiota, dysbiosis. The antibiotic resistome showed a high background of antibiotic resistance genes, which did not significantly change in response to florfenicol. However, the maintenance of Escherichia coli plasmid‐encoded quinolone, oqxB and propagation of mcr‐2, and colistin resistance genes were observed and confirmed by Sanger sequencing. The microbiota of treated animals was enriched with energy harvesting bacteria, common to obese microbial communities. We propose that antibiotic treatment of healthy animals leads to unbalanced, disease‐ and obese‐related microbiota that promotes growth of E. coli carrying resistance genes on mobile elements, potentially increasing the risk of transmission of antibiotic resistant bacteria to humans

Povedenie transaminaz GOT i GPT v syvorotke krovi u detejj inficirovannykh Lamblia intestinalis

In 31 cases with L. intestinalis infection, the GOT and GPT levels were determined on 2-3 occasions (according to Reitman and Frankel) during the treatment; 23 children showed an appreciable increase in the activity of the enzymes; moreover, there were abnormalities in the functional tests of the liver (11 cases)

Protein-adhesive and protein-resistant functionalized silicon surfaces

A series of new ω-alkenyl tertiary amine N-oxides is prepared in solution and immobilized on hydrofluoric acid-etched silicon {111} wafers. These monolayers are characterized by X-ray photoelectron spectroscopy, contact angle measurements, atomic force microscopy (AFM) and tested for their resistance to non-specific protein adhesion with two model proteins, lysozyme and fibrinogen. The use of silicon substrates is found to give good quality tertiary amine N-oxidemonolayers and these new surfaces are found to be significantly better at preventing non-specific protein adhesion than their parent amines as judged by AFM imaging

Coexistence of Toxoplasma gondii and Cytomegalovirus infections in infants

Coexistence of Toxoplasma gondii and Cytomegalovirus infection in 3 dystrophic newborns is discussed. Also the not very characteristic course of the infection is stressed

Coexistence of Toxoplasma gondii and Cytomegalovirus infections in infants

Coexistence of Toxoplasma gondii and Cytomegalovirus infection in 3 dystrophic newborns is discussed. Also the not very characteristic course of the infection is stressed