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Objectives Poultry production is an integral part of agriculture and of the U.S. economy, accounting for millions of eggs and chicken products consumed annually. Most ubiquitous to the poultry industry from farm production to research are broiler and layer poultry operations, with pullet operations at the forefront. Although essential to the cycles of production, there is a dearth of evidence regarding the occupational exposure risks of pullet production. The aim of this case study was to measure total dust and ammonia levels during the growth cycle of pullets. Methods Ammonia and total dust concentrations were measured as single day measurements at three different points of time during the 16.5-week growth cycle of pullet flocks using two fixed sampling stations configured to represent the breathing zone height of poultry workers. Results As birds grew from chicks to hens, concentrations of total dust and ammonia increased. Notably, from 3 weeks-of-age to 9 weeks-of-age concentrations of total dust increased from 1.1-1.2 mg/m3 to 16.0-18.0 mg/m3; and from 9 weeks-of-age to 15 weeks-of-age, dust concentrations reached 43.0-50.0 mg/m3. Concentrations of ammonia also increased from 9 weeks to 15 weeks from 1.1-2.7 ppm to 22.0-30.0 ppm. Conclusions Both levels of ammonia and total dust reached levels that have the potential to induce adverse health effects among farmers raising pullets.

The development of hybrid materials, which combine inorganic with organic materials, is receiving increasing attention by researchers. As a consequence of carbon nanostructures high chemical versatility, they exhibit enormous potential for new highly engineered multifunctional nanotherapeutic agents for cancer therapy. Whereas many groups are working on drug delivery systems for chemotherapy, the use of carbon nanohybrids for radiotherapy is rarely applied. Thus, nanotechnology offers a wide range of solutions to overcome the current obstacles of conventional chemo- and/or radiotherapies. Within this review, the structure and properties of carbon nanostructures (carbon nanotubes, nanographene oxide) functionalized preferentially with different types of polymers (synthetic, natural) are discussed. In short, synthesis approaches, toxicity investigations and anticancer efficacy of different carbon nanohybrids are described.

While the deleterious effects of acute ethyl alcohol intoxication on executive control are well-established, the underlying spatiotemporal brain mechanisms remain largely unresolved. In addition, since the effects of alcohol are noticeable to participants, isolating the effects of the substance from those related to expectations represents a major challenge. We addressed these issues using a double-blind, randomized, parallel, placebo-controlled experimental design comparing the behavioral and electrical neuroimaging acute effects of 0.6 vs 0.02 ​g/kg alcohol intake recorded in 65 healthy adults during an inhibitory control Go/NoGo task. Topographic ERP analyses of covariance with self-reported dose expectations allowed to dissociate their neurophysiological effects from those of the substance.While alcohol intoxication increased response time variability and post-error slowing, bayesian analyses indicated that it did not modify commission error rates. Functionally, alcohol induced topographic ERP modulations over the periods of the stimulus-locked N2 and P3 components, arising from pre-supplementary motor and anterior cingulate areas. In contrast, alcohol decreased the strength of the response-locked anterior cingulate error-related component but not its topography. This pattern indicates that alcohol had a locally specific influence within the executive control network, but disrupted performance monitoring processes via global strength-based mechanisms.We further revealed that alcohol-related expectations induced temporally specific functional modulations of the early N2 stimulus-locked medio-lateral prefrontal activity, a processing phase preceding those influenced by the actual alcohol intake.Our collective findings thus not only reveal the mechanisms underlying alcohol-induced impairments in impulse control and error processing, but also dissociate substance- from expectations- related functional effects.

A free radical polymerization method was adopted for the fabrication of hybrid hydrogel films based on acrylamide and polyethylene glycol dimethacrylate as plasticizing and crosslinking agents, respectively, to be employed as smart skin bandages. Electro-sensitivity, biocompatibility and proteolytic properties were conferred to the final polymer networks by introducing graphene oxide (0.5% w/w), gelatin or trypsin (10% w/w) in the polymerization feed. The physical chemical and mechanical characterization of hybrid materials was performed by means of determination of protein content, Raman spectroscopy, thermogravimetric analysis and measurement of tensile strength. The evaluation of both water affinity and curcumin release profiles (analyzed by suitable mathematical modelling) upon application of an external electric stimulation in the 0-48 voltage range, confirmed the possibility to modulate the release kinetics. Proper proteolytic tests showed that the trypsin enzymatic activity was retained by 80% upon immobilization. Moreover, for all samples, we observed a viability higher than 94% in normal human fibroblast cells (MRC-5), while a reduction of methicillin-resistant Staphylococcus aureus CFU mL-1 (90%) was obtained with curcumin loaded samples.

With the aim to effectively deliver methotrexate (MTX) to breast cancer cells, we designed a nanocarrier system (DC) derived from the self-assembly of a dextran-curcumin conjugate prepared via enzyme chemistry with immobilized laccase acting as a solid biocatalyst. Nanoparticles consisted of homogeneously dispersed nanospheres with a mean diameter of 290 nm, as characterized by combined transmission electron microscopy and dynamic light scattering investigations. DC was able to control the MTX release overtime (t1/2 value of 310 min), with cell internalization studies proving its presence inside MCF-7 cytoplasm. Finally, improved MTX efficacy was obtained in viability assays, and attributed to the synergy of curcumin moieties and loaded MTX as underlined by a combination index (CI) &lt, 1.

Selective vectorization of Cisplatin (CisPt) to Glioblastoma U87 cells was exploited by the fabrication of a hybrid nanocarrier composed of magnetic &gamma, Fe2O3 nanoparticles and nanographene oxide (NGO). The magnetic component, obtained by annealing magnetite Fe3O4 and characterized by XRD measurements, was combined with NGO sheets prepared via a modified Hummer&rsquo, s method. The morphological and thermogravimetric analysis proved the effective binding of &gamma, Fe2O3 nanoparticles onto NGO layers. The magnetization measured under magnetic fields up to 7 Tesla at room temperature revealed superparamagnetic-like behavior with a maximum value of MS = 15 emu/g and coercivity HC &asymp, 0 Oe within experimental error. The nanohybrid was found to possess high affinity towards CisPt, and a rather slow fractional release profile of 80% after 250 h. Negligible toxicity was observed for empty nanoparticles, while the retainment of CisPt anticancer activity upon loading into the carrier was observed, together with the possibility to spatially control the drug delivery at a target site.

A multi-functional composite to be employed as a dressing material was prepared by combining hydrogel and microparticle systems. For the synthesis of the hydrogel counterpart, a free radical polymerization was carried out using a gelatin–curcumin conjugate, previously obtained through immobilized laccase catalysis, and polyethylene glycol dimethacrylate as a functional element, plasticizer, and crosslinker. The hydrogel was found to possess high water affinity, biocompatibility, and the ability to reduce the H2O2-induced oxidative stress on MRC-5 cells by 30%. The spherical microparticle system (mean diameter of 1.75 μm) was prepared by self-assembly of a keratin-methacrylated polyethylene glycol-40 stearate derivative synthesized by a free radical reaction. The final composite, prepared by absorption of microparticles on the hydrogel system, was found to be effective as a support for enhanced cell growth (3.5 times). Furthermore, a reduction of methicillin-resistant Staphylococcus aureus proliferation by 1 log10 CFU was reached taking advantage of the sustained release of the antimicrobial quercetin.

With the aim to obtain a site-specific doxorubicin (DOX) delivery in neuroblastoma SH-SY5Y cells, we designed an hybrid nanocarrier combining graphene oxide (GO) and magnetic iron oxide nanoparticles (MNPs), acting as core elements, and a curcumin&ndash, human serum albumin conjugate as functional coating. The nanohybrid, synthesized by redox reaction between the MNPs@GO system and albumin bioconjugate, consisted of MNPs@GO nanosheets homogeneously coated by the bioconjugate as verified by SEM investigations. Drug release experiments showed a pH-responsive behavior with higher release amounts in acidic (45% at pH 5.0) vs. neutral (28% at pH 7.4) environments. Cell internalization studies proved the presence of nanohybrid inside SH-SY5Y cytoplasm. The improved efficacy obtained in viability assays is given by the synergy of functional coating and MNPs constituting the nanohybrids: while curcumin moieties were able to keep low DOX cytotoxicity levels (at concentrations of 0.44&ndash, 0.88 &micro, M), the presence of MNPs allowed remote actuation on the nanohybrid by a magnetic field, increasing the dose delivered at the target site.