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The synthesis of globins in the chick embryo before the onset of circulation has been studied in situ by specific immunofluorescence labelling of embryonic sections and by labelling newly synthesized proteins in ovo and in vitro in embryonic explants with [3Hjleucine. The presence of major primitive haemoglobins is observed by 28 h of incubation. The minor primitive haemoglobins become detectable by immunofluorescence after 40 h of development, shortly before the onset of circulation. 3H-labelling shows that one definitive a chain is synthesized, though in low concentration, from the initial globin detection. The other definitive a chain is observed in embryos of at least 40 h of development. The relative concentration of the two definitive α chains changes rapidly with development indicating a specific mechanism of regulation. An erythropoietic site is observed in the wall of the dorsal aorta in embryos of about 45–50 h of development. From the initial detection, those cells contain all four primitive embryonic haemoglobins, in contrast to what is observed for the cells of the blood islands.

The use of biological self-assembling materials, plant virus nanoparticles in particular, appears very intriguing as it allows a great choice of symmetries and dimensions, easy chemical and biological engineering of both surface and/or internal cavity as well as safe and rapid production in plants. In this perspective, we present an initial evaluation of the safety profile of two structurally different plant viruses produced in Nicotiana benthamiana L. plants: the filamentous Potato virus X and the icosahedral Tomato bushy stunt virus. In vitro haemolysis assay was used to test the cytotoxic effects, which could arise by pVNPs interaction with cellular membranes, while early embryo assay was used to evaluate toxicity and teratogenicity in vivo. Data indicates that these structurally robust particles, still able to infect plants after incubation in serum up to 24. h, have neither toxic nor teratogenic effects in vitro and in vivo. This work represents the first safety-focused characterization of pVNPs in view of their possible use as drug delivery carriers. © 2015 Elsevier B.V.

The pulmonary route is one of the main strategies investigated to improve tuberculosis therapy. The aim of this study was to develop a simple and scalable method to produce capreomycin inhalable powders to use as supergeneric. In vitro antimycobacterial activity and in vivo acute toxicity were assessed using agar proportion susceptibility test on Mycobacterium tuberculosis and chicken chorioallantoic membrane assay, respectively. Capreomycin and three different hydrophobic counterions, namely oleate, linoleate, and linolenate, were combined in solution to obtain hydrophobic ion-pairs that were successively spray-dried. Ion-pairing efficiency was influenced by the spray-dryer employed to produce the powder. In the case of capreomycin oleate, both instruments, mini and nano spray-dryer, were suitable to maintain a high ion-paired content, while for capreomycin linoleate and linolenate, mini spray-dryer was the most appropriate instrument. The three formulations showed morphology and particle sizes potentially suitable for inhalation. Capreornycin oleate and linoleate showed the same efficacy of capreomycin sulfate against M. tuberculosis, while capreomycin linolenate showed a reduced efficacy, even though strain growth was inhibited at 10(-4) mycobacterial inoculum. In vivo acute toxicity studies evidenced the lowest toxic potential for capreomycin oleate when compared to the single components or the other two salts. Overall, capreomycin oleate seems to possess the most promising characteristics to be used as supergenerics in pulmonary tuberculosis treatment. (C) 2012 Elsevier B.V. All rights reserved.

Purpose: The aim of the work was to assess the long-term stability and the safety of lipid nanoparticles intended for brain drug delivery.Methods: Lipid nanoparticles, prepared by high pressure homogenization, were stored at room temperature and 4 degrees C and monitored for their mean hydrodynamic diameter and Gaussian distribution width over time. Cetylpalmitate and polysorbate (R) 80 chemical integrity were investigated by nuclear magnetic resonance on diagnostic signals. Nanoparticle toxicity was assessed in chicken embryos by chorioallantoic membrane assay and in rodents,by brain histological evaluation.Results: Data showed nanoparticle stability at 4 degrees C over a period of time of 4 years with only a limited particle size increase while at room temperature destabilization was observed after 9 months. Nuclear magnetic resonance investigation confirmed the absence (

Chemical identifications of various hemoglobin types were performed on unfractionated erythroid cells derived from chicken embryos at 5 and 7 days of development and on purified primitive and definitive cells. Proteins were pulse-labelled in primitive erythroid cells at various times of culture to identify those actually synthesized. The data show that primitive cells contain and synthesize only embryonic hemoglobins at all stages of maturation and definitive cells contain adult and minor embryonic hemoglobins, but no major embryonic hemoglobins, not even in trace amounts. These results support a model for hemoglobin switch in the chicken embryo based on cell line substitution.