Genetic selection to increase bone strength affects prevalence of keel bone damage and egg parameters in commercially housed laying hens.

The prevalence of keel bone damage as well as external egg parameters of 2 pure lines divergently selected for high (H) and low (L) bone strength were investigated in 2 aviary systems under commercial conditions. A standard LSL hybrid was used as a reference group. Birds were kept mixed per genetic line (77 hens of the H and L line and 201 or 206 hens of the LSL line, respectively, per pen) in 8 pens of 2 aviary systems differing in design. Keel bone status and body mass of 20 focal hens per line and pen were assessed at 17, 18, 23, 30, 36, 43, 52, and 63 wk of age. External egg parameters (i.e., egg mass, eggshell breaking strength, thickness, and mass) were measured using 10 eggs per line at both 38 and 57 wk of age. Body parameters (i.e. tarsus and third primary wing feather length to calculate index of wing loading) were recorded at 38 wk of age and mortality per genetic line throughout the laying cycle. Bone mineral density (BMD) of 15 keel bones per genetic line was measured after slaughter to confirm assignment of the experimental lines. We found a greater BMD in the H compared with the L and LSL lines. Fewer keel bone fractures and deviations, a poorer external egg quality, as well as a lower index of wing loading were found in the H compared with the L line. Mortality was lower and production parameters (e.g., laying performance) were higher in the LSL line compared with the 2 experimental lines. Aviary design affected prevalence of keel bone damage, body mass, and mortality. We conclude that selection of specific bone traits associated with bone strength as well as the related differences in body morphology (i.e., lower index of wing loading) have potential to reduce keel bone damage in commercial settings. Also, the housing environment (i.e., aviary design) may have additive effects.

[Contrast-enhanced ultrasound for characterisation of focal liver lesions, practical advice]. / Kontrastmittelsonografie zur Charakterisierung von Lebertumoren: Praktische Aspekte.

This review article reports on evidence-based and clinical aspects of contrast-enhanced ultrasound of liver masses. The advanced possibilities of contrast-enhanced ultrasound to detect and characterise liver tumors are described as well as limitations and pitfalls of the method. The choice of the ultrasound device and contrast agents as well as the qualifications of the examiners according to guidelines are discussed.

H/L ratio as a measurement of stress in laying hens - methodology and reliability.

Measuring the ratio of heterophils and lymphocytes (H/L) in response to different stressors is a standard tool for assessing long-term stress in laying hens but detailed information on the reliability of measurements, measurement techniques and methods, and absolute cell counts is often lacking. Laying hens offered different sites of the nest boxes at different ages were compared in a two-treatment crossover experiment to provide detailed information on the procedure for measuring and the difficulties in the interpretation of H/L ratios in commercial conditions. H/L ratios were pen-specific and depended on the age and aviary system. There was no effect for the position of the nest. Heterophiles and lymphocytes were not correlated within individuals. Absolute cell counts differed in the number of heterophiles and lymphocytes and H/L ratios, whereas absolute leucocyte counts between individuals were similar. The reliability of the method using relative cell counts was good, yielding a correlation coefficient between double counts of r > 0.9. It was concluded that population-based reference values may not be sensitive enough to detect individual stress reactions and that the H/L ratio as an indicator of stress under commercial conditions may not be useful because of confounding factors and that other, non-invasive, measurements should be adopted.

Nano-sized and micro-sized polystyrene particles affect phagocyte function.

Adverse effect of nanoparticles may include impairment of phagocyte function. To identify the effect of nanoparticle size on uptake, cytotoxicity, chemotaxis, cytokine secretion, phagocytosis, oxidative burst, nitric oxide production and myeloperoxidase release, leukocytes isolated from human peripheral blood, monocytes and macrophages were studied. Carboxyl polystyrene (CPS) particles in sizes between 20 and 1,000 nm served as model particles. Twenty nanometers CPS particles were taken up passively, while larger CPS particles entered cells actively and passively. Twenty nanometers CPS were cytotoxic to all phagocytes, ≥500 nm CPS particles only to macrophages. Twenty nanometers CPS particles stimulated IL-8 secretion in human monocytes and induced oxidative burst in monocytes. Five hundred nanometers and 1,000 nm CPS particles stimulated IL-6 and IL-8 secretion in monocytes and macrophages, chemotaxis towards a chemotactic stimulus of monocytes and phagocytosis of bacteria by macrophages and provoked an oxidative burst of granulocytes. At very high concentrations, CPS particles of 20 and 500 nm stimulated myeloperoxidase release of granulocytes and nitric oxide generation in macrophages. Cytotoxic effect could contribute to some of the observed effects. In the absence of cytotoxicity, 500 and 1,000 nm CPS particles appear to influence phagocyte function to a greater extent than particles in other sizes.

Design of nest access grids and perches in front of the nests: Influence on the behavior of laying hens.

In aviary systems for laying hens, it is important to provide suitable nest access platforms in front of the nests, allowing hens to reach and explore each of the nests easily. This access platform is needed to achieve good nest acceptance by the hens and thereby prevent mislaid eggs. In the present experiment, the behavior of hens using 2 different nest access platforms, a plastic grid and 2 wooden perches, was examined. Furthermore, the nests were placed on both sides of the aviary rack (corridor side and outdoor side), either integrated into the aviary rack itself (integrated nest; IN) or placed on the walls of the pens (wall nest; WN), resulting in a 2 × 2 factorial design Four thousand five hundred white laying hens were housed in 20 test pens. The eggs in the nests and mislaid eggs were collected daily, and the behavior of hens on the nest accesses was filmed during wk 25 and 26, using focal observation and scan sampling methods. More balancing, body contact, and agonistic interactions were expected for nests with perches, whereas more walking and nest inspections were expected for nests with grids. There were more mislaid eggs and balancing found in pens equipped with nests with wooden perches. More agonistic interactions and balancing, less standing, and a longer duration of nest inspection were found with the WN compared with the IN. Interactions between platform design and position of the nests were found for duration of nest visits, body contact, and walking, with the highest amount for WN equipped with plastic grids. Nests on the corridor side were favored by the hens. Nest-related behaviors, such as nest inspection, standing, and walking, decreased over time as did the number of hens on the nest accesses, whereas sitting increased. These results indicate that the hens had more difficulties in gripping the perches as designed. The lower number of hens on the nest access platforms in front of IN may be due to a better distribution around nests and tier changes within the aviary rack. Based on these results, grids rather than perches provide for improved nesting behavior.

Nest use is influenced by the positions of nests and drinkers in aviaries.

The influence of the nest location and the placement of nipple drinkers on nest use by laying hens in a commercial aviary was assessed. Twenty pens in a laying hen house were equipped with the same commercial aviary system, but the pens differed in the nest location and the placement of nipple drinkers. Nests were placed along the walls in 10 pens, and nipple drinkers were installed in front of the nests in 5 of these pens. The other 10 pens were equipped with nests placed on a tier within the aviary (integrated nests). Nipple drinkers were installed in front of the nests in 5 of these pens. A total of 225 Lohmann Selected Leghorns were housed per pen. The hens were offered 4 nests per pen: 2 facing the service corridor of the laying hen house and 2 facing the outdoor area. The numbers of nest eggs and mislaid eggs were counted daily per pen. At 25, 36, and 43 wk of age, the nest platforms were videotaped and the behavior of laying hens in front of the nests was analyzed. The nest location affected the stationary and locomotive behaviors in front of the nests. Hens in front of the integrated nests and the nests with drinkers displayed more stationary behaviors than hens in front of wall-placed nests or nests without drinkers. No difference in the number of nest eggs could be detected, but the integration of the nests inside the aviary led to a more even distribution of hens while nest searching. In the pens with wall-placed nests, significantly more hens laid eggs in the nests at the wall near the service corridor than at the wall near the outdoor area. Due to this imbalance, crowding in front of the preferred nests occurred and pushing and agonistic interactions on the nest platforms were significantly more frequent. Placement of nipple drinkers in front of nests had no effect on the number of eggs laid in those nests.

Do antidiabetic medications play a specific role in differentiated thyroid cancer compared to other cancer types?

The risk for differentiated thyroid cancer, like for many other types of cancer, is increased in obese individuals and people with intermediate hyperglycaemia. The incidence of all cancers, with the exception of thyroid cancer, is also increased in type 2 diabetes mellitus patients. The review compares the prevalence of thyroid carcinoma and other cancers in obese, people with intermediate hyperglycaemia and patients with diabetes and summarizes mode of action and anti-tumourigenic effect of common antidiabetic medications. The over-expression of dipeptidyl peptidase IV in the tumours, not seen in the other cancer types, is suggested as a potential reason for the unique situation in thyroid cancer.

Influence of front curtain design on nest choice by laying hens.

1. The aim of this study was to investigate the effect of front curtains, one-piece (OP) or sliced in stripes (SL), on the hens' nest preference and laying behaviour in an aviary system. We predicted that hens prefer SL-nests as they could perform nest inspections and enter and leave the nest along its whole width leading to fewer conflicts and more settled laying behaviour. 2. Eight pens containing 20 White Leghorn laying hens were equipped with two roll-away nests, one with OP and one with SL curtains. Laying behaviour was recorded for two days at peak lay in weeks 25 and 26. 3. More nest visits and more nest entries and exits along the whole width of the nest were counted in SL-nests. More sitting events without egg laying were performed in the OP-nests. No differences were found in the number of hens visiting the nests, egg number or aggressive behaviour. 4. Hens appeared to value the seclusion and protection provided by a closed front curtain. However, sliced curtains provided more opportunities to perform nest inspections.

Investigation of Cellular Interactions of Lipid-Structured Nanoparticles With Oral Mucosal Epithelial Cells.

Lipid-based nanosystems enable intracellular delivery of drugs in the oral cavity for the treatment of local diseases. To rationally design such systems, suitable matrix compositions and particle properties need to be identified, and manufacturing technologies that allow reproducible production have to be applied. This is a prerequisite for the reliable and predictable performance of in-vitro biological studies. Here, we showed that solid lipid nanoparticles (SLN, palmitic acid) and nanostructured lipid carriers (NLC, palmitic acid and oleic acid in different ratios) with a size of 250 nm, a negative zeta potential, and a polydispersity index (PdI) of less than 0.3 can be reproducibly prepared by high-pressure homogenization using quality by design and a predictive model. SLN and NLC were colloidally stable after contact with physiological fluid and did not form agglomerates. The in-vitro studies clearly showed that besides particle size, surface charge and hydrophobicity, matrix composition had a significant effect. More specifically, the addition of the liquid lipid oleic acid increased the cellular uptake capacity without changing the underlying uptake mechanism. Regardless of the matrix composition, caveolin-mediated endocytosis was the major route of uptake, which was confirmed by particle localization in the endoplasmic reticulum. Thus, this work provides useful insights into the optimal composition of lipid carrier systems to enhance the intracellular uptake capacity of drugs into the oral mucosa.

Decrease in dipeptidyl peptidase IV activity is linked to the efficacy of differentiating compounds in follicular thyroid carcinoma cell lines.

Metastasized differentiated thyroid carcinoma is treated by surgery followed by radioiodine remnant ablation. The application of differentiating agents is a possibility of increasing the efficacy of radioiodine therapy. We evaluated DPP IV and aminopeptidase N, both linked to malignancy in thyroid carcinoma, and dipeptidyl peptidase II activities in human follicular thyroid carcinoma cell lines upon treatment with retinol, apicidine, and lovastatin as differentiating agents. Decrease of dipeptidyl peptidase IV (DPP IV) activity may play a role in the differentiating action. In the human cancer cell lines FTC 138 and 238, high DPP IV and low aminopeptidase N activities were recorded. Retinol treatment induced increases in thyroid-specific protein expression [thyroglobulin and sodium-iodide symporter (NIS)], increase in iodide uptake, and decrease in thymidine uptake accompanied by decrease in DPP IV activity. Decreases in DPP IV activities were also seen upon apicidine and lovastatin treatment, which also increased differentiation of the transformed thyrocytes. Our results demonstrate a link between decrease in DPP IV activity and increase in iodide uptake upon stimulation with differentiating agents.

Effects of housing, perches, genetics, and 25-hydroxycholecalciferol on keel bone deformities in laying hens.

Several studies have shown a high prevalence of keel bone deformities in commercial laying hens. The aim of this project was to assess the effects of perch material, a vitamin D feed additive (25-hydroxyvitamin D(3); HyD, DSM Nutritional Products, Basel, Switzerland), and genetics on keel bone pathology. The study consisted of 2 experiments. In the first experiment, 4,000 Lohmann Selected Leghorn hens were raised in aviary systems until 18 wk of age. Two factors were investigated: perch material (plastic or rubber-coated metal) and feed (with and without HyD). Afterward, the hens were moved to a layer house with 8 pens with 2 aviary systems. Daily feed consumption, egg production, mortality, and feather condition were evaluated. Every 6 wk, the keel bones of 10 randomly selected birds per pen were palpated and scored. In the second experiment, 2,000 Lohmann Brown (LB) hens and 2,000 Lohmann Brown parent stock (LBPS) hens were raised in a manner identical to the first experiment. During the laying period, the hens were kept in 24 identical floor pens but equipped with different perch material (plastic or rubber-coated metal). The same variables were investigated as in the first experiment. No keel bone deformities were found during the rearing period in either experiment. During the laying period, deformities gradually appeared and reached a prevalence of 35% in the first experiment and 43.8% in the second experiment at the age of 65 and 62 wk, respectively. In the first experiment, neither HyD nor the aviary system had any significant effect on the prevalence of keel bone deformities. In the second experiment, LBPS had significantly fewer moderate and severe deformities than LB, and rubber-coated metal perches were associated with a higher prevalence of keel bone deformities compared with plastic perches. The LBPS laid more but smaller eggs than the LB. Again, HyD did not affect the prevalence of keel bone deformities. However, the significant effect of breed affiliation strongly indicates a sizeable genetic component that may provide a basis for targeted selection.

Prevalence of keel bone deformities in Swiss laying hens.

The goal of this study was to evaluate the prevalence of keel bone deformities of laying hens in Switzerland. The keel bones of 100 end-of-lay hens from each of 39 flocks (3900 in total) were palpated. On average, 25·4% of the hens had moderately or severely deformed keel bones and the overall prevalence including slight deformities was 55%. 3. Variation between flocks was considerable. Thus, the prevalence of moderately or severely deformed keel bones ranged from 6 to 48%, and the overall prevalence including slight deformities ranged from 20 to 83%. Aviary housing was associated with a higher prevalence of total, and severe or moderate deformations, compared with floor pens. There were no significant differences in the number of deformities between the different plumage colours, hybrids or perch materials.

Albumin-based nanoparticles as magnetic resonance contrast agents: II. Physicochemical characterisation of purified and standardised nanoparticles.

We are developing a nanoparticulate histochemical reagent designed for histochemistry in living animals (molecular imaging), which should finally be useful in clinical imaging applications. The iterative development procedure employed involves conceptual design of the reagent, synthesis and testing of the reagent, then redesign based on data from the testing; each cycle of testing and development generates a new generation of nanoparticles, and this report describes the synthesis and testing of the third generation. The nanoparticles are based on human serum albumin and the imaging modality selected is magnetic resonance imaging (MRI). Testing the second particle generation with newly introduced techniques revealed the presence of impurities in the final product, therefore we replaced dialysis with diafiltration. We introduced further testing methods including thin layer chromatography, arsenazo III as chromogenic assay for gadolinium, and several versions of polyacrylamide gel electrophoresis, for physicochemical characterisation of the nanoparticles and intermediate synthesis compounds. The high grade of chemical purity achieved by combined application of these methodologies allowed standardised particle sizes to be achieved (low dispersities), and accurate measurement of critical physicochemical parameters influencing particle size and imaging properties. Regression plots confirmed the high purity and standardisation. The good degree of quantitative physicochemical characterisation aided our understanding of the nanoparticles and allowed a conceptual model of them to be prepared. Toxicological screening demonstrated the extremely low toxicity of the particles. The high magnetic resonance relaxivities and enhanced mechanical stability of the particles make them an excellent platform for the further development of MRI molecular imaging.

Albumin-based nanoparticles as magnetic resonance contrast agents: I. Concept, first syntheses and characterisation.

To develop a platform for molecular magnetic resonance imaging, we prepared gadolinium-bearing albumin-polylactic acid nanoparticles in the size range 20-40 nm diameter. Iterative cycles of design and testing upscaled the synthesis procedures to gram amounts for physicochemical characterisation and for pharmacokinetic testing. Morphological analyses showed that the nanoparticles were spheroidal with rough surfaces. Particle sizes were measured by direct transmission electron microscopical measurements from negatively contrasted preparations, and by use of photon correlation spectroscopy; the two methods each documented nanoparticle sizes less than 100 nm and generally 10-40 nm diameter, though with significant intrabatch and interbatch variability. The particles' charge sufficed to hold them in suspension. HSA retained its tertiary structure in the particles. The nanoparticles were stable against turbulent flow conditions and against heat, though not against detergents. MRI imaging of liquid columns was possible at nanoparticle concentrations below 10 mg/ml. The particles were non-cytotoxic, non-thrombogenic and non-immunogenic in a range of assay systems developed for toxicity testing of nanoparticles. They were micellar prior to lyophilisation, but loosely structured aggregated masses after lyophilisation and subsequent resuspension. These nanoparticles provide a platform for further development, based on non-toxic materials of low immunogenicity already in clinical use, not expensive, and synthesized using methods which can be upscaled for industrial production.

A yeast mutant showing diagnostic markers of early and late apoptosis.

A Saccharomyces cerevisiae mutant in cell division cycle gene CDC48 shows typical markers of apoptosis: membrane staining with annexin V, indicating an exposure of phosphatidylserine at the outer layer of the cytoplasmic membrane; intense staining, using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method, indicating DNA fragmentation; and chromatin condensation and fragmentation. The coordinate occurrence of these events at different locations in the cell, which have no obvious connection except their relation to apoptosis, implies the presence of the molecular machinery performing the basic steps of apoptosis already in yeast. Saccharomyces cerevisiae may prove a suitable model to trace the roots of apoptosis.

Oxygen stress: a regulator of apoptosis in yeast.

Oxygen radicals are important components of metazoan apoptosis. We have found that apoptosis can be induced in the yeast Saccharomyces cerevisiae by depletion of glutathione or by low external doses of H2O2. Cycloheximide prevents apoptotic death revealing active participation of the cell. Yeast can also be triggered into apoptosis by a mutation in CDC48 or by expression of mammalian bax. In both cases, we show oxygen radicals to accumulate in the cell, whereas radical depletion or hypoxia prevents apoptosis. These results suggest that the generation of oxygen radicals is a key event in the ancestral apoptotic pathway and offer an explanation for the mechanism of bax-induced apoptosis in the absence of any established apoptotic gene in yeast.

Ranking carcinogens for regulation.

In the issue of 9 August 1968 (p. 541), Science printed the Nobel lecture of Hans A. Bethe on "Energy production in stars." Eddington had at one time hypothesized that stellar energy arises from complete annihilation of matter. The energy to be set free by such a process, if it could occur, would be enough to supply the sun's radiation for 15,000 billion years. In the lecture, this number was erroneously given as 1500 billion years.

[Effect of quality assessment assurance in 2002 (before starting the German colorectal cancer screening programme by colonoscopy) on the quality of reprocessing of flexible endoscopes--a nationwide analysis]. / Effekt der Qualitätssicherungsvereinbarung von 2002 (bei Einführung der Vorsorgekoloskopie) auf die Qualität der Aufbereitung flexibler Koloskope - eine bundesweite Analyse.

BACKGROUND: International studies in the 1990 s and the HYGEA study from Germany in 2002 revealed prevalences of around 50 % of microbiological contaminations in reprocessed flexible endoscopes. Before introducing the colorectal cancer screening programme by colonoscopy in Germany in 2002, the Kassenärztliche Bundesvereinigung (KBV) and the key stakeholders of the public health insurance system agreed on a quality assessment assurance for reprocessing endoscopes where the qualification for refund for colonoscopies from the public health system was made conditional on adequate qualifications of the gastroenterologist; on a minimum number of performed procedures per year; and on adequate endoscope reprocessing documented by negative surveillance cultures two times per year. This study is an implementation and outcome evaluation of the quality assessment assurance in colonoscopy in Germany. METHODS: The following data - per year and per Kassenärztliche Vereinigung (KV) - were obtained from the KBV: the number of endoscopic units performing therapeutic and/or screening colonoscopies within each KV; the results of all microbiological surveillance tests of reprocessing quality (two per year per unit); the number of failed surveillance tests and re-tests; and the number of qualifications for refund from the public health system cancelled due to repeated failure of microbiological surveillance tests. RESULTS: The percentages of actually performed hygiene control tests (out of those prescribed by the assurance system) reached 95 % already in 2004 and remained above or close to this level thereafter. After the introduction of the quality assessment assurance, the percentage of failed microbiological surveillance tests dropped significantly and steadily from close to 17 % in 2003 to below 4 % in 2007. CONCLUSIONS: This study evidences 1. the successful implementation of the quality assessment assurance in Germany and 2. a substantial improvement in the quality of reprocessing flexible endoscopes achieved by these measures with a drop from 50 % of failed tests observed before the introduction in 2000 - 2001 to below 4 % in 2007.

Impact of drug particle shape on permeability and cellular uptake in the lung.

The generation of inhalable sized particles (1-5 µm) usually involves a particle-processing step; most commonly milling but spray drying has shown to be a suitable alternative. Besides particle size, processing may affect other particle properties, like shape and solid-state. For example, spray drying of salbutamol sulphate leads to spherical shaped predominantly amorphous particles whereas jet milling frequently maintains the irregular shape and the crystallinity of the raw material. The aim of the present study was to investigate whether particle properties, especially shape, change the biological action of the inhaled particles as well. Therefore, highly water soluble salbutamol sulphate and poorly water soluble budesonide were compared regarding dissolution, permeation and preferential uptake by epithelial cells compared to macrophages after jet milling and spray drying. For both drugs the spray dried, predominantly amorphous, particles resulted in lower respirable fractions, but higher permeability and cell uptake rates compared to the needle shaped, predominantly crystalline particles. The distinct particle properties did not affect the dissolution behaviour of salbutamol sulphate. In turn for drugs with lower solubility (budesonide), spray dried particles dissolved slower compared to jet milled particles. Preferential uptake by macrophages was higher for spray dried particles, suggesting that processing may improve targeted delivery. The comparison between murine cell lines and human monocyte derived macrophages primary cells showed similar trends in rate and preference of particle uptake.

An automatable platform for genotoxicity testing of nanomaterials based on the fluorometric γ-H2AX assay reveals no genotoxicity of properly surface-shielded cadmium-based quantum dots.

The large number of nanomaterial-based applications emerging in the materials and life sciences and the foreseeable increasing use of these materials require methods that evaluate and characterize the toxic potential of these nanomaterials to keep safety risks to people and environment as low as possible. As nanomaterial toxicity is influenced by a variety of parameters like size, shape, chemical composition, and surface chemistry, high throughput screening (HTS) platforms are recommended for assessing cytotoxicity. Such platforms are not yet available for genotoxicity testing. Here, we present first results obtained for application-relevant nanomaterials using an automatable genotoxicity platform that relies on the quantification of the phosphorylated histone H2AX (γ-H2AX) for detecting DNA double strand breaks (DSBs) and the automated microscope system AKLIDES® for measuring integral fluorescence intensities at different excitation wavelengths. This platform is used to test the genotoxic potential of 30 nm-sized citrate-stabilized gold nanoparticles (Au-NPs) as well as micellar encapsulated iron oxide nanoparticles (FeOx-NPs) and different cadmium (Cd)-based semiconductor quantum dots (QDs), thereby also searching for positive and negative controls as reference materials. In addition, the influence of the QD shell composition on the genotoxic potential of these Cd-based QDs was studied, using CdSe cores as well as CdSe/CdS core/shell and CdSe/CdS/ZnS core/shell/shell QDs. Our results clearly revealed the genotoxicity of the Au-NPs and its absence in the FeOx-NPs. The genotoxicity of the Cd-QDs correlates with the shielding of their Cd-containing core, with the core/shell/shell architecture preventing genotoxicity risks. The fact that none of these nanomaterials showed cytotoxicity at the chosen particle concentrations in a conventional cell viability assay underlines the importance of genotoxicity studies to assess the hazardous potential of nanomaterials.