Ethologic and Economic Examination of Aviary Housing for Commercial Laying Flocks

The authors report that the results of their research indicate that appropriate housing is necessary for intensively kept hens and that the housing has to correspond to the vital needs and natures of the animals

Ethologic and Economic Examination of Aviary Housing for Commercial Laying Flocks

The result of our work shows that appropriate housing is necessary for intensively kept hens and that the housing has to correspond to the vital needs and the nature of the animals. This is important for two reasons: a) the innate needs of the birds must be satisfied; b) for the proper development of the animal and successful egg production. The housing facilities should allow the following functional cycles without restrictions: Social organization: the structuring of a group or unit of animals. Locomotion: walking, running, fluttering, flying. Feeding behavior: search for food and water, food and water pecking, ground scratching, scraping. Comfort behavior: plumage care, stretching, dust bathing. Resting behavior: standing, sleeping. Sexual behavior: egg laying, nest building behavior. Each one of these functional cycles requires its own area in the hen house. The hen house has to be arranged in order to accommodate the needs of the animals

Conditional human VEGF‐mediated vascularization in chicken embryos using a novel temperature‐inducible gene regulation (TIGR) system

Advanced heterologous transcription control systems for adjusting desired transgene expression are essential for gene function assignments, drug discovery, manufacturing of difficult to produce protein pharmaceuticals and precise dosing of gene‐based therapeutic interventions. Conversion of the Streptomyces albus heat shock response regulator (RheA) into an artificial eukaryotic transcription factor resulted in a vertebrate thermosensor (CTA; cold‐inducible transactivator), which is able to adjust transcription initiation from chimeric target promoters (PCTA) in a low‐temperature‐ inducible manner. Evaluation of the temperature‐dependent CTA-PCTA interaction using a tailored ELISA‐like cell‐free assay correlated increased affinity of CTA for PCTA with temperature downshift. The temperature‐inducible gene regulation (TIGR) system enabled tight repression in the chicken bursal B‐cell line DT40 at 41°C as well as precise titration of model product proteins up to maximum expression at or below 37°C. Implantation of microencapsulated DT40 cells engineered for TIGR‐controlled expression of the human vascular endothelial growth factor A (hVEGF121) provided low‐temperature‐induced VEGF‐mediated vascularization in chicken embryo

Identification and Functional Characterization of Gene Components of Type VI Secretion System in Bacterial Genomes

A new secretion system, called the Type VI Secretion system (T6SS), was recently reported in Vibrio cholerae, Pseudomonas aeruginosa and Burkholderia mallei. A total of 18 genes have been identified to be belonging to this secretion system in V. cholerae. Here we attempt to identify presence of T6SS in other bacterial genomes. This includes identification of orthologous sequences, conserved motifs, domains, families, 3D folds, genomic islands containing T6SS components, phylogenetic profiles and protein-protein association of these components. Our analysis indicates presence of T6SS in 42 bacteria and its absence in most of their non-pathogenic species, suggesting the role of T6SS in imparting pathogenicity to an organism. Analysis of genomic regions containing T6SS components, phylogenetic profiles and protein-protein association of T6SS components indicate few additional genes which could be involved in this secretion system. Based on our studies, functional annotations were assigned to most of the components. Except one of the genes, we could group all the other genes of T6SS into those belonging to the puncturing device, and those located in the outer membrane, transmembrane and inner membrane. Based on our analysis, we have proposed a model of T6SS and have compared the same with the other bacterial secretion systems

Mesenchymal stromal cell activation by breast cancer secretomes in bioengineered 3D microenvironments

Mesenchymal stromal cells (MSCs) are key contributors of the tumour microenvironment and are known to promote cancer progression through reciprocal communication with cancer cells, but how they become activated is not fully understood. Here, we investigate how breast cancer cells from different stages of the metastatic cascade convert MSCs into tumour-associated MSCs (TA-MSCs) using unbiased, global approaches. Using mass spectrometry, we compared the secretomes of MCF-7 cells, invasive MDA-MB-231 cells, and sublines isolated from bone, lung, and brain metastases and identified ECM and exosome components associated with invasion and organ-specific metastasis. Next, we used synthetic hydrogels to investigate how these different secretomes activate MSCs in bioengineered 3D microenvironments. Using kinase activity profiling and RNA sequencing, we found that only MDA-MB-231 breast cancer secretomes convert MSCs into TA-MSCs, resulting in an immunomodulatory phenotype that was particularly prominent in response to bone-tropic cancer cells. We have investigated paracrine signalling from breast cancer cells to TA-MSCs in 3D, which may highlight new potential targets for anticancer therapy approaches aimed at targeting tumour stroma

In Macrophages, Caspase-1 Activation by SopE and the Type III Secretion System-1 of S. Typhimurium Can Proceed in the Absence of Flagellin

The innate immune system is of vital importance for protection against infectious pathogens. Inflammasome mediated caspase-1 activation and subsequent release of pro-inflammatory cytokines like IL-1β and IL-18 is an important arm of the innate immune system. Salmonella enterica subspecies 1 serovar Typhimurium (S. Typhimurium, SL1344) is an enteropathogenic bacterium causing diarrheal diseases. Different reports have shown that in macrophages, S. Typhimurium may activate caspase-1 by at least three different types of stimuli: flagellin, the type III secretion system 1 (T1) and the T1 effector protein SopE. However, the relative importance and interdependence of the different factors in caspase-1 activation is still a matter of debate. Here, we have analyzed their relative contributions to caspase-1 activation in LPS-pretreated RAW264.7 macrophages. Using flagellar mutants (fliGHI, flgK) and centrifugation to mediate pathogen-host cell contact, we show that flagellins account for a small part of the caspase-1 activation in RAW264.7 cells. In addition, functional flagella are of key importance for motility and host cell attachment which is a prerequisite for mediating caspase-1 activation via these three stimuli. Using site directed mutants lacking several T1 effector proteins and flagellin expression, we found that SopE elicits caspase-1 activation even when flagellins are absent. In contrast, disruption of essential genes of the T1 protein injection system (invG, sipB) completely abolished caspase-1 activation. However, a robust level of caspase-1 activation is retained by the T1 system (or unidentified T1 effectors) in the absence of flagellin and SopE. T1-mediated inflammasome activation is in line with recent work by others and suggests that the T1 system itself may represent the basic caspase-1 activating stimulus in RAW264.7 macrophages which is further enhanced independently by SopE and/or flagellin

Quantifying the Proteolytic Release of Extracellular Matrix-Sequestered VEGF with a Computational Model

BACKGROUND: VEGF proteolysis by plasmin or matrix metalloproteinases (MMPs) is believed to play an important role in regulating vascular patterning in vivo by releasing VEGF from the extracellular matrix (ECM). However, a quantitative understanding of the kinetics of VEGF cleavage and the efficiency of cell-mediated VEGF release is currently lacking. To address these uncertainties, we develop a molecular-detailed quantitative model of VEGF proteolysis, used here in the context of an endothelial sprout. METHODOLOGY AND FINDINGS: To study a cell's ability to cleave VEGF, the model captures MMP secretion, VEGF-ECM binding, VEGF proteolysis from VEGF165 to VEGF114 (the expected MMP cleavage product of VEGF165) and VEGF receptor-mediated recapture. Using experimental data, we estimated the effective bimolecular rate constant of VEGF165 cleavage by plasmin to be 328 M(-1) s(-1) at 25 degrees C, which is relatively slow compared to typical MMP-ECM proteolysis reactions. While previous studies have implicated cellular proteolysis in growth factor processing, we show that single cells do not individually have the capacity to cleave VEGF to any appreciable extent (less than 0.1% conversion). In addition, we find that a tip cell's receptor system will not efficiently recapture the cleaved VEGF due to an inability of cleaved VEGF to associate with Neuropilin-1. CONCLUSIONS: Overall, VEGF165 cleavage in vivo is likely to be mediated by the combined effect of numerous cells, instead of behaving in a single-cell-directed, autocrine manner. We show that heparan sulfate proteoglycans (HSPGs) potentiate VEGF cleavage by increasing the VEGF clearance time in tissues. In addition, we find that the VEGF-HSPG complex is more sensitive to proteases than is soluble VEGF, which may imply its potential relevance in receptor signaling. Finally, according to our calculations, experimentally measured soluble protease levels are approximately two orders of magnitude lower than that needed to reconcile levels of VEGF cleavage seen in pathological situations

The Spectrin Cytoskeleton Is Crucial for Adherent and Invasive Bacterial Pathogenesis

Various enteric bacterial pathogens target the host cell cytoskeletal machinery as a crucial event in their pathogenesis. Despite thorough studies detailing strategies microbes use to exploit these components of the host cell, the role of the spectrin-based cytoskeleton has been largely overlooked. Here we show that the spectrin cytoskeleton is a host system that is hijacked by adherent (Entropathogenic Escherichia coli [EPEC]), invasive triggering (Salmonella enterica serovar Typhimurium [S. Typhimurium]) and invasive zippering (Listeria monocytogenes) bacteria. We demonstrate that spectrin cytoskeletal proteins are recruited to EPEC pedestals, S. Typhimurium membrane ruffles and Salmonella containing vacuoles (SCVs), as well as sites of invasion and comet tail initiation by L. monocytogenes. Spectrin was often seen co-localizing with actin filaments at the cell periphery, however a disconnect between the actin and spectrin cytoskeletons was also observed. During infections with S. Typhimurium ΔsipA, actin-rich membrane ruffles at characteristic sites of bacterial invasion often occurred in the absence of spectrin cytoskeletal proteins. Additionally, early in the formation of L. monocytogenes comet tails, spectrin cytoskeletal elements were recruited to the surface of the internalized bacteria independent of actin filaments. Further studies revealed the presence of the spectrin cytoskeleton during SCV and Listeria comet tail formation, highlighting novel cytoplasmic roles for the spectrin cytoskeleton. SiRNA targeted against spectrin and the spectrin-associated proteins severely diminished EPEC pedestal formation as well as S. Typhimurium and L. monocytogenes invasion. Ultimately, these findings identify the spectrin cytoskeleton as a ubiquitous target of enteric bacterial pathogens and indicate that this cytoskeletal system is critical for these infections to progress

Human Neutrophil Elastase Responsive Delivery from Poly(ethylene glycol) Hydrogels

A novel enzyme-responsive hydrogel drug delivery system was developed with the potential to treat inflammation locally. Human neutrophil elastase (HNE) is a serine protease secreted by neutrophils which are the first cells recruited to inflammatory sites. We exploited this cell-secreted enzyme as a biological cue for controlled release. HNE sensitive peptide linkers were immobilized within poly(ethylene glycol) hydrogels using photopolymerization techniques. The kinetics of the enzyme reaction within the gel was tailored by varying the amino acid residues present in the P1 and P1 ′ substrate positions (immediately adjacent to cleavage location). A novel FRET-based hydrogel platform was designed to characterize the accessibility of the substrate within the cross-linked, macroscopic hydrogel. Lastly, a diffusion-reaction mathematical model with Michaelis-Menten kinetics was developed to predict the overall release profile and captured the initial 80 % of the experimentally observed release. The hydrogel platform presented shows highly controlled release kinetics with potential applications in cellular responsive drug delivery. 1

Functionalization of Carbon Nanomaterial Surface by Doxorubicin and Antibodies to Tumor Markers

The actual task of oncology is effective treatment of cancer while causing a minimum harm to the patient. The appearance of polymer nanomaterials and technologies launched new applications and approaches of delivery and release of anticancer drugs. The goal of work was to test ultra dispersed diamonds (UDDs) and onion-like carbon (OLCs) as new vehicles for delivery of antitumor drug (doxorubicin (DOX)) and specific antibodies to tumor receptors. Stable compounds of UDDs and OLCs with DOX were obtained. As results of work, an effectiveness of functionalization was 2.94 % w/w for OLC-DOX and 2.98 % w/w for UDD-DOX. Also, there was demonstrated that UDD-DOX and OLC-DOX constructs had dose-dependent cytotoxic effect on tumor cells in the presence of trypsin. The survival of adenocarcinoma cells reduced from 52 to 28 % in case of incubation with the UDD-DOX in concentrations from 8.4–2.5 to 670–20 μg/ml and from 72 to 30 % after incubation with OLC-DOX. Simultaneously, antibodies to epidermal growth factor maintained 75 % of the functional activity and specificity after matrix-assisted pulsed laser evaporation deposition. Thus, the conclusion has been made about the prospects of selected new methods and approaches for creating an antitumor agent with capabilities targeted delivery of drugs