Mutagenicity and genotoxicity assessment of the emerging mycotoxin Versicolorin A, an Aflatoxin B1 precursor

Aflatoxin B1 (AFB1) is the most potent natural carcinogen among mycotoxins. Versicolorin A (VerA) is a precursor of AFB1 biosynthesis and is structurally related to the latter. Although VerA has already been identified as a genotoxin, data on the toxicity of VerA are still scarce, especially at low concentrations. The SOS/umu and miniaturised version of the Ames test in Salmonella Typhimurium strains used in the present study shows that VerA induces point mutations. This effect, like AFB1, depends primarily on metabolic activation of VerA. VerA also induced chromosomal damage in metabolically competent intestinal cells (IPEC-1) detected by the micronucleus assay. Furthermore, results from the standard and enzyme-modified comet assay confirmed the VerA-mediated DNA damage, and we observed that DNA repair pathways were activated upon exposure to VerA, as indicated by the phosphorylation and/or relocation of relevant DNA-repair biomarkers (γH2AX and 53BP1/FANCD2, respectively). In conclusion, VerA induces DNA damage without affecting cell viability at concentrations as low as 0.03 μM, highlighting the danger associated with VerA exposure and calling for more research on the carcinogenicity of this emerging food contaminant.

Protozoan parasites and free-living amoebae contamination in organic leafy green vegetables and strawberries from Spain

In this study, the presence of Acanthamoeba spp., Blastocystis sp., Cryptosporidium spp., Cyclospora cayetanensis, Entamoeba histolytica, Giardia sp., Toxoplasma gondii and Vermamoeba vermiformis was assessed in organic leafy green vegetables (lettuce, spinach, cabbage) and fruits (strawberry), which are usually consumed raw. A total of 110 organic samples were collected in Valencia (Spain). Protozoa were concentrated before detection by immunofluorescence (Cryptosporidium spp. and Giardia sp.) or real-time qPCR (Acanthamoeba spp., Blastocystis sp., C. cayetanensis, E. histolytica, T. gondii and V. vermiformis). The most abundant protozoa in organic vegetables and berry fruits were Acanthamoeba (65.5%), followed by T. gondii (37.2%), V. vermiformis (17.3%), C. cayetanensis (12.7%), Cryptosporidium spp. (6.8%), Blastocystis sp. (1.8%) and Giardia sp. (1.7%). E. histolytica was not found in any of the organic samples. Thus, results showed that consumers can be exposed to protozoan parasites by consuming organic vegetables and berry fruits. This is the first report in Spain describing the presence of the protozoan pathogens Acanthamoeba spp., Blastocystis sp., C. cayetanensis, T. gondii and V. vermiformis, Cryptosporidium spp. and Giardia sp. in organic fresh produce. The results of this research will help determine the risk of foodborne protozoan parasites on organic leafy greens and strawberries that are available at local markets.

The phenotype of the gut region is more stably retained than developmental stage in piglet intestinal organoids

Intestinal organoids are innovative in vitro tools to study the digestive epithelium. The objective of this study was to generate jejunum and colon organoids from suckling and weaned piglets in order to determine the extent to which organoids retain a location-specific and a developmental stage-specific phenotype. Organoids were studied at three time points by gene expression profiling for comparison with the transcriptomic patterns observed in crypts in vivo. In addition, the gut microbiota and the metabolome were analyzed to characterize the luminal environment of epithelial cells at the origin of organoids. The location-specific expression of 60 genes differentially expressed between jejunum and colon crypts from suckling piglets was partially retained (48%) in the derived organoids at all time point. The regional expression of these genes was independent of luminal signals since the major differences in microbiota and metabolome observed in vivo between the jejunum and the colon were not reproduced in vitro. In contrast, the regional expression of other genes was erased in organoids. Moreover, the developmental stage-specific expression of 30 genes differentially expressed between the jejunum crypts of suckling and weaned piglets was not stably retained in the derived organoids. Differentiation of organoids was necessary to observe the regional expression of certain genes while it was not sufficient to reproduce developmental stage-specific expression patterns. In conclusion, piglet intestinal organoids retained a location-specific phenotype while the characteristics of developmental stage were erased in vitro. Reproducing more closely the luminal environment might help to increase the physiological relevance of intestinal organoids.

Intestinal toxicity of the new type A trichothecenes, NX and 3ANX

NX and its acetylated form 3ANX are two new type A trichothecenes produced by Fusarium graminearum whose toxicity is poorly documented. The aim of this study was to obtain a general view of the intestinal toxicity of these toxins. Deoxynivalenol (DON), which differs from NX by the keto group at C8, served as a benchmark. The viability of human intestinal Caco-2 cells decreased after 24 h of exposure to 3 μM NX (-21.4%), 3 μM DON (-20.2%) or 10 μM 3ANX (-17.4%). Histological observations of porcine jejunal explants exposed for 4 h to 10 μM of the different toxins showed interstitial edema and cellular debris. Explants exposed to NX also displayed cell vacuolization, a broken epithelial barrier and high loss of villi. Whole transcriptome profiling revealed that NX, DON and 3ANX modulated 369, 146 and 55 genes, respectively. Functional analyses indicated that the three toxins regulate the same gene networks and signaling pathways mainly; cell proliferation, differentiation, apoptosis and growth, and particularly immune and pro-inflammatory responses. Greater transcriptional impacts were observed with NX than with DON. In conclusion, our data revealed that the three toxins have similar impacts on the intestine but of different magnitude: NX > DON ≫ 3ANX. NX and 3ANX should consequently be included in overall risk analysis linked to the presence of trichothecenes in our diet.

Exposure to Zearalenone Leads to Metabolic Disruption and Changes in Circulating Adipokines Concentrations in Pigs

Zearalenone (ZEN) is a mycotoxin classified as an endocrine disruptor. Many endocrine disruptors are also metabolic disruptors able to modulate energy balance and inflammatory processes in a process often involving a family of protein hormones known as adipokines. The aim of our study was to elucidate the role of ZEN as metabolic disruptor in pigs by investigating the changes in energy balance and adipokines levels in response to different treatment diets. To this end, weaned piglets (n = 10/group) were exposed to either basal feed or feed contaminated with 680 and 1620 µg/kg ZEN for 28 days. Serum samples collected at days 7 and 21 were subjected to biochemistry analysis, followed by determination of adipokine levels using a combined approach of protein array and ELISA. Results indicate that ZEN has an impact on lipid and glucose metabolism that was different depending on the dose and time of exposure. In agreement with these changes, ZEN altered circulating adipokines concentrations, inducing significant changes in adiponectin, resistin, and fetuin B. Our results suggest that ZEN may function as a natural metabolism-disrupting chemical.

Analysis of conflicts with wild carnivores in the Humid Chaco, Argentina

Interactions between humans and carnivores tend to be conflictual, especially due to predation on domestic animals. As certain landscape characteristics predispose the occurrence of carnivore attacks, spatial modelling of predation events can be particularly useful when developing management plans. In this study we determined the incidence of predation on the mortality of domestic animals by interviewing local inhabitants. In addition, we identified the spatial variables that explain the distribution of the conflicts and we created a two–scale model based on the Maxent algorithm. The results showed that Puma concolor (41.2 %) and the foxes Lycalopex gymnocercus and Cerdocyon thous (33.3 %) were the most conflictive species. Predation accounted for only 5.6 % of the causes of domestic animal mortality. The distribution models showed that the most probable variables for predicting conflicts were the distance from the roads, livestock density and the proportion of anthropized areas. High–risk areas represented 28 % of the study area and were distributed in broad patches around the protected areas and in the eastern sector of the area.

Proteomic Changes Associated With Sperm Fertilizing Ability in Meat-Type Roosters

The molecular basis of male fertility remains unclear, especially in chickens, where decades of genetic selection increased male fertility variability as a side effect. As transcription and translation are highly limited in sperm, proteins are key molecules defining their functionality, making proteomic approaches one of the most adequate methods to investigate sperm capacity. In this context, it is interesting to combine complementary proteomic approaches to maximize the identification of proteins related to sperm-fertilizing ability. In the present study, we aimed at identifying proteins related to fertility in meat-type roosters, showing fertility variability. Fertile roosters (fertility rates higher than 70% after artificial insemination) differed from subfertile roosters (fertility rates lower than 40%) in their sperm mass motility. Fertile and subfertile sperm protein contents were compared using two complementary label-free quantitative proteomic methods: Intact Cell MALDI-TOF-Mass Spectrometry and GeLC-MS/MS. Combining the two strategies, 57 proteins were identified as differentially abundant. Most of them were described for the first time as differentially abundant according to fertility in this species. These proteins were involved in various molecular pathways including flagellum integrity and movement, mitochondrial functions, sperm maturation, and storage in female tract as well as oocyte–sperm interaction. Collectively, our data improved our understanding of chicken sperm biology by revealing new actors involved in the complexity of male fertility that depends on multiple cell functions to reach optimal rates. This explains the inability of reductionist in vitro fertility testing in predicting male fertility and suggests that the use of a combination of markers is a promising approach.

Proteome changes induced by a short, non-cytotoxic exposure to the mycoestrogen zearalenone in the pig intestine

Intestinal epithelial homeostasis is regulated by a complex network of signaling pathways. Among them is estrogen signaling, important for the proliferation and differentiation of epithelial cells, immune signaling and metabolism. The mycotoxin zearalenone (ZEN) is an estrogen disruptor naturally found in food and feed. The exposure of the intestine to ZEN has toxic effects including alteration of the immune status and is possibly implicated in carcinogenesis, but the molecular mechanisms linked with these effects are not clear. Our objective was to explore the proteome changes induced by a short, non-cytotoxic exposure to ZEN in the intestine using pig jejunal explants. Our results indicated that ZEN promotes little proteome changes, but significantly related with an induction of ERα signaling and a consequent disruption of highly interrelated signaling cascades, such as NF-κB, ERK1/2, CDX2 and HIF1α. The toxicity of ZEN leads also to an altered immune status characterized by the activation of the chemokine CXCR4/SDF-1 axis and an accumulation of MHC-I proteins. Our results connect the estrogen disrupting activity of ZEN with its intestinal toxic effect, associating the exposure to ZEN with cell-signaling disorders similar to those involved in the onset and progression of diseases such as cancer and chronic inflammatory disorders. SIGNIFICANCE: The proteomics results presented in our study indicate that the endocrine disruptor activity of ZEN is able to regulate a cascade of highly inter-connected signaling events essential for the small intestinal crypt-villus cycle and immune status. These molecular mechanisms are also implicated in the onset and progress of intestinal immune disorders and cancer indicating that exposure to ZEN could play an important role in intestinal pathogenesis.

[Diagnostic accuracy of the tri-ponderal mass index in identifying the unhealthy metabolic obese phenotype in obese patients]

INTRODUCTION

The metabolically healthy obese (MHO) phenotype defines obese patients who have preserved insulin sensitivity and absence of metabolic complications. This phenotype is associated with a lower risk of cardiovascular disease and type2 diabetes in adulthood.

OBJECTIVES

To determine the prevalence of MHO and the metabolically unhealthy obesity (MUO) phenotype in a cohort of obese children and adolescents and to establish the predictive capacity of the tri-ponderal mass index (TMI) and other anthropometric parameters in order to identify these patients.

PATIENTS AND METHODS

A cross-sectional study was conducted on 239 obese patients (125males) from 8 to 18years of age. Grade3 obesity was present in 45.9% of the patients. ROC curves were used to find the best cut-off point for: TMI, body mass index (BMI), BMI z-score (BMIzs), and waist/height index (WHI). MHO components: plasma blood glucose, plasma triglycerides, HDL-cholesterol, and blood pressure.

RESULTS

The prevalence of MUO in the study cohort was 62.4%. No differences between genders were observed, and it was increasing with the age and obesity degree. The TMI has a sensitivity of 75.8 and a specificity of 42.2 to identify the MUO patients. The best cut-off point for TMI is 18.7kg/m³, for BMI it was 30.4kg/m², for BMIzs +3.5SD, and 0.62 for WHI.

CONCLUSIONS

The diagnostic accuracy of TMI in identifying obese adolescents with metabolic risk was similar to BMI and WHI. However, the TMI is much simpler to use and simplifies the categorization of the obesity in both genders.

Intrinsic alterations in peripheral neutrophils from cystic fibrosis newborn piglets

BACKGROUND

The hallmark of the cystic fibrosis (CF) lung disease is a neutrophil dominated lung environment that is associated to chronic lung tissue destruction and ultimately the patient's death. It is unclear whether the exacerbated neutrophil response is primary related to a defective CFTR or rather secondary to chronic bacterial colonization and inflammation. Here, we hypothesized that CF peripheral blood neutrophils present intrinsic alteration at birth before the start of an inflammatory process.

METHODS

Peripheral blood neutrophils were isolated from newborn CFTR^+/+ and CFTR^-/- piglets. Neutrophils immunophenotype was evaluated by flow cytometry. Lipidomic and proteomic profile were characterized by liquid chromatography/tandem mass spectrometry (LC-MS/MS), intact cell matrix-assisted laser desorption/ionization mass spectrometry (ICM-MS) followed by top-down high-resolution mass spectrometry (HRMS), respectively. The ability of CF neutrophils to kill pseudomonas aeruginosa was also evaluated.

RESULTS

Polyunsaturated fatty acid metabolites analysis did not show any difference between CFTR^+/+ and CFTR^-/- neutrophils. On the other hand, a predictive mathematical model based on the ICM-MS proteomic profile was able to discriminate between both genotypes. Top-down proteomic analysis identified 19 m/z differentially abundant masses that corresponded mainly to proteins related to the antimicrobial response and the generation of reactive oxygen species (ROS). However, no alteration in the ability of CFTR^-/- neutrophils to kill pseudomonas aeruginosa in vitro was observed.

CONCLUSIONS

ICM-MS demonstrated that CFTR^-/- neutrophils present intrinsic alterations already at birth, before the presence of any infection or inflammation.

Acute Exposure to Zearalenone Disturbs Intestinal Homeostasis by Modulating the Wnt/β-Catenin Signaling Pathway

The mycotoxin zearalenone (ZEN), which frequently contaminates cereal-based human food and animal feed, is known to have an estrogenic effect. The biological response associated with exposure to ZEN has rarely been reported in organs other than the reproductive system. In the intestine, several studies suggested that ZEN might stimulate molecular changes related to the activation of early carcinogenesis, but the molecular mechanisms behind these events are not yet known. In this study, we investigated gene expression and changes in protein abundance induced by acute exposure to ZEN in the jejunum of castrated male pigs using an explant model. Our results indicate that ZEN induces the accumulation of ERα but not ERβ, modulates Wnt/β-catenin and TGF-β signaling pathways, and induces molecular changes linked with energy sensing and the antimicrobial activity without inducing inflammation. Our results confirm that the intestine is a target for ZEN, inducing changes that promote cellular proliferation and could contribute to the onset of intestinal pathologies.

Ultrafast transient liquid assisted growth of high current density superconducting films

The achievement of high growth rates in YBa₂Cu₃O₇ epitaxial high-temperature superconducting films has become strategic to enable high-throughput manufacturing of long length coated conductors for energy and large magnet applications. We report on a transient liquid assisted growth process capable of achieving ultrafast growth rates (100 nm s⁻¹) and high critical current densities (5 MA cm⁻² at 77 K). This is based on the kinetic preference of Ba-Cu-O to form transient liquids prior to crystalline thermodynamic equilibrium phases, and as such is a non-equilibrium approach. The transient liquid-assisted growth process is combined with chemical solution deposition, proposing a scalable method for superconducting tapes manufacturing. Additionally, using colloidal solutions, the growth process is extended towards fabrication of nanocomposite films for enhanced superconducting properties at high magnetic fields. Fast acquisition in situ synchrotron X-ray diffraction and high resolution scanning transmission electron microscopy (STEM) become crucial measurements in disentangling key aspects of the growth process.

High throughput manufacturing of long length coated conductors requires fast epitaxial growth of high-temperature superconducting films. Here, Soler et al. report an ultrafast growth rates and high critical current densities of YBa₂Cu₃O₇ films using a transient liquid-assisted growth method.

A step towards stereotactic navigation during pelvic surgery: 3D nerve topography

Background

Long-term morbidity after multimodal treatment for rectal cancer is suggested to be mainly made up by nerve-injury-related dysfunctions. Stereotactic navigation for rectal surgery was shown to be feasible and will be facilitated by highlighting structures at risk of iatrogenic damage. The aim of this study was to investigate the ability to make a 3D map of the pelvic nerves with magnetic resonance imaging (MRI).

Methods

A systematic review was performed to identify a main positional reference for each pelvic nerve and plexus. The nerves were manually delineated in 20 volunteers who were scanned with a 3-T MRI. The nerve identifiability rate and the likelihood of nerve identification correctness were determined.

Results

The analysis included 61 studies on pelvic nerve anatomy. A main positional reference was defined for each nerve. On MRI, the sacral nerves, the lumbosacral plexus, and the obturator nerve could be identified bilaterally in all volunteers. The sympathetic trunk could be identified in 19 of 20 volunteers bilaterally (95%). The superior hypogastric plexus, the hypogastric nerve, and the inferior hypogastric plexus could be identified bilaterally in 14 (70%), 16 (80%), and 14 (70%) of the 20 volunteers, respectively. The pudendal nerve could be identified in 17 (85%) volunteers on the right side and in 13 (65%) volunteers on the left side. The levator ani nerve could be identified in only a few volunteers. Except for the levator ani nerve, the radiologist and the anatomist agreed that the delineated nerve depicted the correct nerve in 100% of the cases.

Conclusion

Pelvic nerves at risk of injury are usually visible on high-resolution MRI with dedicated scanning protocols. A specific knowledge of their course and its application in stereotactic navigation is suggested to improve quality of life by decreasing the likelihood of nerve injury.

Electronic supplementary material

The online version of this article (10.1007/s00464-018-6086-3) contains supplementary material, which is available to authorized users.

Stent-Assisted Angioplasty of Intracranial Vertebrobasilar Atherosclerosis: The Best Therapeutic Option in Recurrent Transient Ischemic Events Unresponsive to Anticoagulant Treatments

Atherosclerotic stenosis of the posterior circulation refractory to medical treatment generally has a poor prognosis resulting in a high morbidity-mortality rate and the recurrence of ischemic events. Extracranial bypass in the vertebrobasilar system is possible but is also associated with high morbidity (3–21%) and mortality (13–55%)1,2, and has not been demonstrated to reduce the risk of stroke. Percutaneous angioplasty alone has also not shown favorable results, and further, has been associated with a remarkable number of complications. The improvement resulting from endovascular therapy has taken the treatment of this pathology to a new dimension. We describe eight patients with severe symptomatic basilar artery stenosis who, in addition to medical therapy, were treated by our service with angioplasty and stent placement. Three of them received urgent treatment. All patients suffering from severe stenosis of the basilar artery were treated by the insertion of balloon expandable stents. The degree of pre-stent stenosis was approximately 80% in all cases, and was reduced to 5–10% after the stent implant. There were no complications during treatment. There has not been a recurrence of symptoms or a new ischemic lesion during the one-year follow-up period. Endovascular therapy with a balloon expandable stent or angioplasty plus stent are presented as improved choices for treatment of patients with severe basilar artery stenosis refractory to medical treatment.

Intact Cell MALDI-TOF MS on Sperm: A Molecular Test For Male Fertility Diagnosis

Currently, evaluation of sperm quality is primarily based on in vitro measures of sperm function such as motility, viability and/or acrosome reaction. However, results are often poorly correlated with fertility, and alternative diagnostic tools are therefore needed both in veterinary and human medicine. In a recent pilot study, we demonstrated that MS profiles from intact chicken sperm using MALDI-TOF profiles could detect significant differences between fertile/subfertile spermatozoa showing that such profiles could be useful for in vitro male fertility testing. In the present study, we performed larger standardized experimental procedures designed for the development of fertility- predictive mathematical models based on sperm cell MALDI-TOF MS profiles acquired through a fast, automated method. This intact cell MALDI-TOF MS-based method showed high diagnostic accuracy in identifying fertile/subfertile males in a large male population of known fertility from two distinct genetic lineages (meat and egg laying lines). We additionally identified 40% of the m/z peaks observed in sperm MS profiles through a top-down high-resolution protein identification analysis. This revealed that the MALDI-TOF MS spectra obtained from intact sperm cells contained a large proportion of protein degradation products, many implicated in important functional pathways in sperm such as energy metabolism, structure and movement. Proteins identified by our predictive model included diverse and important functional classes providing new insights into sperm function as it relates to fertility differences in this experimental system. Thus, in addition to the chicken model system developed here, with the use of appropriate models these methods should effectively translate to other animal taxa where similar tests for fertility are warranted.

Growth promotion in pigs by oxytetracycline coincides with down regulation of serum inflammatory parameters and of hibernation-associated protein HP-27

The growth promoting effect of supplementing animal feed with antibiotics like tetracycline has traditionally been attributed to their antibiotic character. However, more evidence has been accumulated on their direct anti-inflammatory effect during the last two decades. Here we used a pig model to explore the systemic molecular effect of feed supplementation with sub therapeutic levels of oxytetracycline (OTC) by analysis of serum proteome changes. Results showed that OTC promoted growth, coinciding with a significant down regulation of different serum proteins related to inflammation, oxidation and lipid metabolism, confirming the anti-inflammatory mechanism of OTC. Interestingly, apart from the classic acute phase reactants also down regulation was seen of a hibernation associated plasma protein (HP-27), which is to our knowledge the first description in pigs. Although the exact function in non-hibernators is unclear, down regulation of HP-27 could be consistent with increased appetite, which is possibly linked to the anti-inflammatory action of OTC. Given that pigs are good models for human medicine due to their genetic and physiologic resemblance, the present results might also be used for rational intervention in human diseases in which inflammation plays an important role such as obesity, type 2 diabetes and cardiovascular diseases.

The localization and differential expression of Serum Amyloid A in bovine liver and adipose tissue depots

In this article the localization of the acute phase protein Serum Amyloid A (SAA) in different depots of bovine adipose tissue (AT) and liver is reported. Quantitative (Real Time) PCR was paired to immunohistochemistry after the production of a specific polyclonal antibody. SAA's mRNA was found in all analyzed AT depots included in the present study, the AT located in the withers being the major source of SAA mRNA. A polyclonal antibody was raised against bovine SAA and was used to validate gene expression analyses. Western Blotting confirmed that SAA is present in all the seven adipose tissue depots include in the present experiment. Anti-SAA polyclonal antibody also stained diffusely adipocytes. In liver, intracytoplasmic immunolabeling was observed in hepatocytes. Staining was generally mild and not diffuse: negative hepatocytes were intermixed with positive ones. A positive intracytoplasmic immunostaining was occasionally observed in endothelial cells lining small blood vessels within AT septa and liver parenchyma. Our data confirm that bovine AT may provide an important source of SAA in healthy subjects. It remains to be determined which is the contribution of AT in the serum concentration of SAA.

Identification of the major regenerative III protein (RegIII) in the porcine intestinal mucosa as RegIIIγ, not RegIIIα

During the last years, an antimicrobial protein from the RegIII family has been consistently identified as one of the main up-regulated mRNA transcripts in the pig small intestinal mucosa during different infections such as enterotoxigenic Escherichia coli (ETEC). This transcript has been mainly referred to in the literature as pancreatitis-associated protein (PAP/RegIIIα). However, the identity of this transcript has not been confirmed, and no evidence of its expression at the protein level is available in the literature, because the absence of a specific antibody. In this study, we first unequivocally identified the PAP/RegIII family protein mainly expressed in ETEC infected pig intestine as RegIIIγ by 2D-DIGE and MALDI-TOF/TOF. This shows that the pig differs from species like human and mice in that RegIIIγ (and not RegIIIα) might be the major RegIII isotype during intestinal infection. Immunoblotting analysis with a specifically generated polyclonal rabbit antibody revealed that pig RegIIIγ is expressed throughout the intestinal tract, but most abundantly in the ileum. Although a higher abundance of mRNA was paralleled by higher protein abundance, a lack of linear relationship was found between RegIIIγ mRNA and protein abundances in the jejunal mucosa, the latter most pronounced in the case of natural infection. This may be related to the secretory nature of RegIIIγ. This would mean that the antimicrobial protein RegIIIγ is a good candidate as a non-invasive faecal intestinal health biomarker in swine.

Proteomic approaches to study the pig intestinal system

One of the major challenges in pig production is managing digestive health to maximize feed conversion and growth rates, but also to minimize treatment costs and to warrant public health. There is a great interest in the development of useful tools for intestinal health monitoring and the investigation of possible prophylactic/ therapeutic intervention pathways. A great variety of in vivo and in vitro intestinal models of study have been developed in the recent years. The understanding of such a complex system as the intestinal system (IS), and the study of its physiology and pathology is not an easy task. Analysis of such a complex system requires the use of systems biology techniques, like proteomics. However, for a correct interpretation of results and to maximize analysis performance, a careful selection of the IS model of study and proteomic platform is required. The study of the IS system is especially important in the pig, a species whose farming requires a very careful management of husbandry procedures regarding feeding and nutrition. The incorrect management of the pig digestive system leads directly to economic losses related suboptimal growth and feed utilization and/or the appearance of intestinal infections, in particular diarrhea. Furthermore, this species is the most suitable experimental model for human IS studies. Proteomics has risen as one of the most promising approaches to study the pig IS. In this review, we describe the most useful models of IS research in porcine and the different proteomic platforms available. An overview of the recent findings in pig IS proteomics is also provided.

Different stressors elicit different responses in the salivary biomarkers cortisol, haptoglobin, and chromogranin A in pigs

Most commonly, salivary cortisol is used in pig stress assessment, alternative salivary biomarkers are scarcely studied. Here, salivary cortisol and two alternative salivary biomarkers, haptoglobin and chromogranin A were measured in a pig stress study. Treatment pigs (n = 24) were exposed to mixing and feed deprivation, in two trials, and compared to untreated controls (n = 24). Haptoglobin differed for feed deprivation vs control. Other differences were only found within treatment. Treatment pigs had higher salivary cortisol concentrations on the mixing day (P < 0.05). Chromogranin A concentrations were increased on the day of refeeding (P < 0.05). Haptoglobin showed a similar pattern to chromogranin A. Overall correlations between the salivary biomarkers were positive. Cortisol and chromogranin A were moderately correlated (r = 0.49, P < 0.0001), correlations between other markers were weaker. The present results indicate that different types of stressors elicited different physiological stress responses in the pigs, and therefore including various salivary biomarkers in stress evaluation seems useful.

Detection of potential markers for systemic disease in saliva of pigs by proteomics: a pilot study

Animals with different health status have been studied in order to extend the knowledge about protein composition of porcine saliva samples and to discover potential salivary markers for systemic disease in porcine production. Clinical examination of animals was performed at farm level where 10 healthy pigs and 10 animals with evident clinical signs of disease were randomly selected. Saliva and blood samples were obtained and afterwards animals were humanely sacrificed to perform a complete necropsy. Levels of two acute phase proteins, haptoglobin and C-reactive protein, were used to identify possible active infections of the animals. Moreover, serological analysis, to the main porcine infectious diseases in the area, was performed. Salivary proteins were separated by two-dimensional gel electrophoresis followed by mass spectrometry for the identification of specific proteins. A total of 58 spots out of 75 were successfully identified by MS, which correspond to 20 unique proteins. Two different approaches were used to perform a statistical comparison of saliva protein patterns from healthy and diseased animals using the relative spot volume (% spot volume/total volume of all spot in the gel, approach "A") or taking also into account the total protein content of each saliva sample (μg of spot/mL of saliva, approach "B"). Both analyses showed three proteins in common that are differentially regulated between states. However, approach B was selected for biomarker searching since it gave an estimation of protein concentration and showed differential expression of proteins between both health states in a total of 10 proteins, which were up-regulated in disease. Mass spectrometric analysis identified those proteins as salivary lipocalin, lipocalin 1, double headed protease inhibitor protein, adenosine deaminase, haptoglobin, albumin fragments, S100-A8, S100-A9, S100-A12 and pancreatic alpha amylase. These proteins could be considered as potential salivary markers of disease.

Why working with porcine circulating serum amyloid A is a pig of a job

Serum amyloid A (SAA) is a major acute phase protein in most species, and is widely employed as a health marker. Systemic SAA isoforms (SAA1, and SAA2) are apolipoproteins synthesized by the liver which associate with high density lipoproteins (HDL). Local SAA (SAA3) isoforms are synthesized in other tissues and are present in colostrums, mastitic milk and mammary dry secretions. Of systemic SAA the bulk is monomeric and bound to HDL, and a small proportion is found in serum in a multimeric form with a buried HDL binding site. In most species, systemic SAA could easily be studied by purifying it from serum of diseased individuals by hydrophobic interaction chromatography methods. For years, we were not able to isolate systemic pig SAA using the latter methods, and found that the bulk of pig SAA did not reside in the HDL-rich serum fractions but in the soluble protein fraction mainly as a multimeric protein. Based on these surprising results, we analysed in silico the theoretical properties and predicted the secondary structure of pig SAA by using the published pig primary SAA amino acid sequence. Results of the analysis confirmed that systemic pig SAA had the highest homology with local SAA3 which in other species is the isoform associated with non-hepatic production in tissues such as mammary gland and intestinal epithelium. Furthermore, the primary sequence of the pig SAA N-terminal HDL binding site did differ considerably from SAA1/2. Secondary structure analysis of the predicted alpha-helical structure of this HDL binding site showed a considerable reduction in hydrophobicity compared to SAA1/2. Based on these results, it is argued that systemic acute phase SAA in the pig has the structural properties of locally produced SAA (SAA3). It is proposed that in pig SAA multimers the charged N-terminal sequence is buried, which would explain their different properties. It is concluded that pig systemic SAA is unique compared to other species, which raises questions about the proposed importance of acute phase SAA in HDL metabolism during inflammation in this species.

Fast measurement of serum amyloid A in different specimens from swine by using a new one-step time-resolved fluorescent immunoassay

The objective of the present study was to develop a one-step, fast, competitive time-resolved fluorescent immunoassay to determine porcine serum amyloid A (SAA) by using species-specific reagents. The assay consisted of an all-in-one format involving only 55 min of incubation that was adapted and validated for use in 3 different specimens: serum, saliva, and meat juice. The method had overall within- and between-run coefficients of variation under 8% and 12%, respectively, and coefficients of determination higher than 0.93 for linearity under dilution analysis for all specimens. The limits of detection were 0.32 mg/l, 0.28 mg/l, and 1.74 mg/l for serum, saliva, and meat juice measurements, respectively. Upper and lower limits of quantification were determined for each sample type and resulted in wide assay ranges that allowed a precise SAA measurement in all the fluids investigated. Statistically significant differences (P = 0.0004 for serum and P < 0.0001 for the saliva and meat juice samples) in SAA levels were found when healthy (n = 20) and diseased (n = 20) pigs were compared. The obtained results indicate that this fast, sensitive, and robust assay for SAA measurement could be of use to determine health and welfare status in swine by employing alternative samples to serum.

Development and validation of a novel competitive ELISA for the detection of serum amyloid A in pigs

The objective of this study was to develop a novel competitive ELISA to measure the acute phase protein serum amyloid A (SAA) in pigs using species-specific reagents. Polyclonal antibodies were produced in rabbits immunised with recombinant porcine SAA (rSAA) expressed in Escherichia coli. Both the rSAA and polyclonal antibodies were used to develop a novel competitive assay that was analytically and clinically validated. This assay had within- and between-run coefficients of variation of 8.6% and 25%, respectively, and demonstrated a high level of accuracy as determined by linearity-under-dilution (correlation coefficient, r=0.965). The analytical and functional limits of detection were 3.3 and 105.02mg/L, and the upper and lower quantification limits were 66.9 and 2.8mg/L, respectively. Statistically significant differences (P<0.0001) were found between the concentrations of SAA in healthy and diseased pigs. This novel assay precisely and sensitively measures SAA levels in pigs and will facilitate the more accurate assessment and study of the acute phase response in this species.

A cost effective simulator for education of ultrasound image interpretation and probe manipulation

Ultrasonography is the lowest cost no risk medical imaging technique. However, reading an ultrasonographic (US) image as well as performing a good US probe positioning remain difficult tasks. Education in this domain is today performed on patients, thus limiting it to the most common cases. In this paper, we present a cost effective simulator that allows US image practice and realistic probe manipulation from CT data. More precisely, we tackle the issue of providing a realistic interface for the probe manipulation with a basic haptic feedback.

Elevated amh gene expression in the brain of male tilapia (Oreochromis niloticus) during testis differentiation

Anti-müllerian hormone (AMH) is expressed in male embryos and represses development of müllerian ducts during testis differentiation in mammals, birds and reptiles. Amh orthologues have been identified in teleosts despite them lacking müllerian ducts. Previously we found sexually dimorphic aromatase activity in tilapia brains before ovarian differentiation. This prompted us to search for further dimorphisms in tilapia brains during sex differentiation and see whether amh is expressed. We cloned the tilapia amh gene and found that it contains 7 exons but no spliced forms. The putative protein presents highest homologies with Amh proteins of pejerrey and medaka as compared to other Perciformes. We analysed amh expression in adult tissues and found elevated levels in testes, ovary and brain. Amh expression was dimorphic with higher levels in XY male brains at 10-15 dpf, when the gonads were still undifferentiated and gonadal amh was not dimorphic. Male brains had 2.7-fold higher amh expression than gonads. Thereafter, amh levels decreased in the brain while they were up-regulated in differentiating testes. Our study indicates that amh is transcribed in male brains already at 10 dpf, suggesting that sexual differentiation may be occurring earlier in tilapia brain than in gonads.

Recent advances in liver imaging

Liver surgery remains a difficult challenge in which preoperative data analysis and strategy definition may play a significant role in the success of the procedure. Medical image processing led to a major improvement of patient care by guiding the surgical gesture. From this initial data, new technologies of virtual reality and augmented reality can increase the potential of such images. The 3D modeling of the liver of patients from their CT scan or MRI thus allows an improved surgical planning. Simulation allows the procedure to be simulated preoperatively and offers the opportunity to train the surgical gesture before carrying it out. These three preoperative steps can be used intraoperatively thanks to the development of augmented reality, which consists of superimposing the preoperative 3D modeling of the patient onto the real intraoperative view of the patient and his/her organs. Augmented reality provides surgeons with a transparent view of the patient. This facilitated the intraoperative identification of the vascular anatomy and the control of the segmental arteries and veins in liver surgery, thus preventing intraoperative bleeding. It can also offer guidance due to the virtual improvement of their real surgical tools, which are tracked in real-time during the procedure. During the surgical procedure, augmented reality, therefore, offers surgeons a transparent view of their patient, which will lead to the automation of the most complex maneuvers. The new ways of processing and analyzing liver images have dramatically changed the approach to liver surgery.

Use of saliva for haptoglobin and C-reactive protein quantifications in porcine respiratory and reproductive syndrome affected pigs in field conditions

The purpose of this study was to study the use of saliva samples as alternative to serum for acute phase protein (APP) quantifications in pigs at field conditions. To this end, haptoglobin (Hp) and C-reactive protein (CRP) concentrations were examined in 100 animals at different ages. Sixty pigs were from a farm with chronic PRRS virus infection and 40 from a specific pathogen free (SPF) farm. A serological study was performed to obtain an overview of the immune status of animals and to evaluate possible concomitant infections in animals with PRRS infection. The results reported in this study showed that both saliva and serum samples had higher APP concentrations in PRRS pigs aged 8-9, 17-18 and 24-25 weeks in conventional herds than SPF pigs of the same age (p<0.05). In addition, increases in APP were obtained with age independently of the health status of the animals. According to the ROC analyses performed, saliva could be a better specimen than serum to quantify Hp and CRP levels in field conditions and may contribute to a more efficient detection of diseased animals at farm level.

Serum Total Sialic Acid in Pigs: New Possibilities for an Old Inflammatory Biomarker

The potential use of total sialic acid (TSA) as an acute-phase biomarker in pigs was investigated through clinical and analytic validation of an automated commercial enzymatic-colorimetric assay. Intra- and interassay precision, accuracy, and detection limit were determined for the analytical validation of the method. The intra- and interassay coefficients of variation (%CV) were 2.27% and 3.99%, respectively, whereas the linearity under dilution calculation resulted in a coefficients of correlation of r = 0.995 and r = 0.999 for TSA high- and low-content serum samples, respectively, which indicated that the automated method was reliable to measure TSA in porcine serum samples. Average serum TSA concentrations in diseased pigs (median: 1779.16 mg/l; 5th percentile: 556.62 mg/l; 95th percentile: 963.06 mg/l) were 2.5-fold higher compared with healthy animals (median: 692.78 mg/l; 5th percentile: 1278.74 mg/l; 95th percentile: 2536.12 mg/l), which indicated that TSA can be considered as a moderate acute phase marker in swine. Therefore, TSA may be useful for detecting inflammatory conditions and could be included in biochemical profiles used to monitor the general status of pigs as a moderate acute phase marker.

Acute Phase Protein Response in Goats

Acute phase proteins (APPs) are important diagnostic indicators of inflammatory disturbances in animals. The objectives of the current study were to validate analytical methods for measuring haptoglobin (Hp), serum amyloid A (SAA), acid soluble glycoprotein (ASG), fibrinogen, and albumin concentrations in goats and to evaluate their response to an inflammatory stimulus in this species. Intra- and interassay coefficients of variation (CVs) were in the range 0.07–9.31% and 1.83–12.68%, respectively, for all APPs and showed good precision. All assays determined APPs in a linear manner at different sample dilutions with high correlation coefficients with the exception of fibrinogen, which was measured by the heat precipitation method. Subcutaneous injection of turpentine oil induced an increase in Hp, SAA, ASG, and fibrinogen serum concentrations and a decrease in albumin concentration.

3D virtual reality and selective vascular control for laparoscopic left hepatic lobectomy

BACKGROUND

Careful control of haemostasis is particularly important in laparoscopic hepatic surgery, since a bloodless operative field results in safer and smoother procedures. A selective vascular control for a left lateral segmentectomy may be facilitated by the use of three-dimensional (3D) virtual reality.

MATERIALS AND METHODS

A 67-year-old male patient presenting with a 3.5-cm hepatocellular carcinoma (HCC) located between segment II and III of the liver was referred for hepatic resection. Transplant was contraindicated due to previous head and neck cancer surgery. Preoperative 3D reconstruction was used for preoperative planning and allowed a virtual resection to be done as well as peroperative simulation.

RESULTS

Five ports were used. The first step was primary control of the hepatic pedicle. 3D virtual-reality reconstruction demonstrated the position of the tumor in the segment and regarding the vessels. The left hepatic artery and the portal vein were successively dissected and controlled. The real anatomy was compared to the virtual-reality reconstruction. Both demonstrated the same anatomy. Vascular section was completed and this resulted in a typical color change of the left lateral segment as well as a small decrease in size. The bisegmentectomy was performed using harmonic dissectors (Autosonix(R), Tyco Healthcare), bipolar cautery, clips, and application of Endo GIA vascular staples (Tyco Healthcare) on the portal pedicles. The procedure was completed following isolation and control of the left hepatic vein. After section, the specimen was placed in a bag and extracted following enlargement of the camera port. Follow-up was uneventful and there was no elevation of hepatic enzymes or postoperative ascites. The patient left the hospital on the fifth postoperative day.

CONCLUSION

3D reconstruction allowed the procedure to be simulated preoperatively. This facilitated the intraoperative identification of the vascular anatomy and the control of the left lateral segment arteries and veins, thus preventing intraoperative bleeding. The use of this approach in preoperative planning is recommended.

Fully automated image-guided needle insertion: application to small animal biopsies

The study of biological process evolution in small animals requires time-consuming and expansive analyses of a large population of animals. Serial analyses of the same animal is potentially a great alternative. However non-invasive procedures must be set up, to retrieve valuable tissue samples from precisely defined areas in living animals. Taking advantage of the high resolution level of in vivo molecular imaging, we defined a procedure to perform image-guided needle insertion and automated biopsy using a micro CT-scan, a robot and a vision system. Workspace limitations in the scanner require the animal to be removed and laid in front of the robot. A vision system composed of a grid projector and a camera is used to register the designed animal-bed with to respect to the robot and to calibrate automatically the needle position and orientation. Automated biopsy is then synchronised with respiration and performed with a pneumatic translation device, at high velocity, to minimize organ deformation. We have experimentally tested our biopsy system with different needles.