First molecular identification of the zoonotic parasite Anisakis pegreffii (Nematoda: Anisakidae) in a paraffin-embedded granuloma taken from a case of human intestinal anisakiasis in Italy

<p>Abstract</p> <p>Background</p> <p>Anisakiasis is an important fish-borne zoonosis provoked by larval stages of nematodes belonging to the genus <it>Anisakis</it>. The detection and identification of human infections is difficult. This is due to: a) the low specificity of the clinical features and symptomatology related to human infections; b) the paucity of diagnostic features of larvae found in granulomatous lesions characteristic of "invasive anisakiasis"; and c) the lack morphological characters diagnostic at the specific level when larvae of <it>Anisakis </it>are detected. Thus, molecular-based diagnostic approaches are warranted.</p> <p>Method</p> <p>We have developed a PCR method that amplifies the DNA of <it>Anisakis </it>spp. in fixed paraffin-embedded tissues. This method was applied to a granuloma removed from a human case of intestinal anisakiasis in Italy. Specific primers of the mtDNA <it>cox2 </it>gene were used and sequence analysis was performed according to the procedures already established for species of <it>Anisakis</it>.</p> <p>Results</p> <p>The sequence obtained (629 bp) was compared with those of the other species of <it>Anisakis </it>which have so far been genetically characterized and with sequences obtained from larval stages of <it>Anisakis </it>collected from the Mediterranean fish <it>Engraulis encrasicolus</it>. This enabled the genetic identification of the larva in the human tissue as <it>A. pegreffii</it>. This is the first instance of human intestinal anisakiasis diagnosed using PCR of DNA purified from a fixed eosinophilic granuloma embedded in paraffin.</p> <p>Conclusion</p> <p>The case of human anisakiasis presented reinforces the pathological significance of the species <it>A. pegreffii </it>to humans. The molecular/genetic methodological approach based on mtDNA <it>cox2 </it>sequence analysis, described here, can allow easy and rapid identification of <it>Anisakis </it>spp. in formalin-fixed and paraffin embedded tissues removed from cases of either gastric or intestinal human anisakiasis.</p

Functional insights into the infective larval stage of Anisakis simplex s.s., Anisakis pegreffii and their hybrids based on gene expression patterns

List of species and specimen used in the phylogenetic tree of Additional file 1. Code of the voucher specimen and accession number for mitochondrial gene COII (*: sequences obtained from GenBank). Labeled are the specimens selected for RNA sequencing (first number, population; second number specimen). A. simplex s.s. – A. pegreffii refers to hybrids haplotype according Abollo et al. [23]. (DOCX 47 kb

Anisakis simplex: from Obscure Infectious Worm to Inducer of Immune Hypersensitivity

Summary: Infection of humans with the nematode worm parasite Anisakis simplex was first described in the 1960s in association with the consumption of raw or undercooked fish. During the 1990s it was realized that even the ingestion of dead worms in food fish can cause severe hypersensitivity reactions, that these may be more prevalent than infection itself, and that this outcome could be associated with food preparations previously considered safe. Not only may allergic symptoms arise from infection by the parasites (“gastroallergic anisakiasis”), but true anaphylactic reactions can also occur following exposure to allergens from dead worms by food-borne, airborne, or skin contact routes. This review discusses A. simplex pathogenesis in humans, covering immune hypersensitivity reactions both in the context of a living infection and in terms of exposure to its allergens by other routes. Over the last 20 years, several studies have concentrated on A. simplex antigen characterization and innate as well as adaptive immune response to this parasite. Molecular characterization of Anisakis allergens and isolation of their encoding cDNAs is now an active field of research that should provide improved diagnostic tools in addition to tools with which to enhance our understanding of pathogenesis and controversial aspects of A. simplex allergy. We also discuss the potential relevance of parasite products such as allergens, proteinases, and proteinase inhibitors and the activation of basophils, eosinophils, and mast cells in the induction of A. simplex-related immune hypersensitivity states induced by exposure to the parasite, dead or alive

Surface soil moisture retrieval on agricultural catchments of Navarre, Spain through RADARSAT-1 SAR data: first results

The importance of soil moisture on many scientific fields like hydrology. meteorology, crop growth or soil erosion has been addressed frequently. Its characterisation has been a difficult task because of its high spatial and temporal variability. Several point based measurement techniques have been developed with different degree of success, but their conversion to spatially distributed values depends on complex geostatistical techniques. Furthermore., sensor installation and maintenance can be quite tedious. In this background, SAR remote sensing sensors provide valuable information on land surface parameters. The backscattering of the SAR signal depends amongst others on the dielectric constant of the observed surface. which is mainly related to the soil surface water content. It also gives spatially distributed information with a resolution adequate for different spatial scales: from medium or small watersheds to agricultural fields. Its periodicity, can be appropriate for calibrating, on a monthly basis.. the simulations of distributed hydrologic modelling tools. The present paper reports the first results of an ongoing research of which the main objective is the development of a simple methodology for the calibration of the soil moisture component of distributed hydrological models using SAR data. Five RADARSAT-1 images, acquired between 27/02/2003 and 02/04/2003 over the Navarre region (Northern Spain) have been processed. The calculated backscattering values have been compared to soil moisture and surface roughness ground measurements. Empirical linear regression models have been fitted at three different scales: point scale,. field scale and catchment scale, showing acceptable correlation between calculated backscattering values and ground measured soil moisture specially at field and watershed scale. However, consistent trends have not been found probably due to differing local conditions such as surface roughness or vegetation cover. Seeking for a more consistent approach, the physically based Integral Equation Method (IEM) model has been applied. Yet., simulations run by the IEM have not been completely successful probably due to an inadequate characterisation of surface roughness

RADARSAT based surface soil moisture retrieval on agricultural catchments of Navarre (Spain)

The present paper, reports the first results of an ongoing research whose main objective is the development of a simple methodology for initialising., and updating the soil moisture component of distributed hydrological models using SAR data. Five RADARSAT-1 images acquired between 27/02/2003 and 02/04/2003 over the Navarre region (Northern Spain) have been processed. Soil moisture, surface roughness and crop parameters have been monitored coinciding with image acquisition dates over La Tejeria experimental watershed (Navarre). Calculated backscattering values have been compared to soil moisture and surface roughness ground measurements fitting empirical linear regression models. In the case of vegetated fields a semi-empirical Water Cloud model has been applied to account for vegetation effects on the observed backscattering values. Acceptable correlation has been observed between calculated backscattering values and ground measured soil moisture at field and watershed scale, although variability was high between fields belonging to the same vegetation and roughness classes. The physically based Integral Equation Method (IEM) model has been applied seeking for a more consistent approach. IEM reflected observed backscattering trends. However, dispersion was high probably due to an inadequate characterisation of surface roughness variability