74 research outputs found

    Moving rom Histopathology to Molecular Tools in the Diagnosis of Molluscs Diseases of Concern under EU Legislation

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    10 páginas, 2 tablas.-- This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these termsOne of the main factors limiting molluscs production is the presence of pathogens and diseases. Disease agent transfer via transfers of live molluscs has been a major cause of disease outbreaks and epizootics. Because of that, the European Union has adopted several decisions and directives, the last in 2006 (2006/88/EC) to control movements of marine organisms over the European countries. Once the disease is established in a determined area its eradication is a complicated task because life cycle of pathogens are not completely known and only a good and early diagnosis of the disease could be the most appropriate way to deal with it. Besides, molluscs do not have an adaptive immune response and vaccination strategies are not possible. Molluscs listed diseases under EU legislation are mainly protozoan parasites, that's why histological techniques are recognized for their diagnosis. However, molecular techniques are being increasingly used primarily as confirmatory techniques of the presence of the pathogens but also in disease monitoring programs. Research perspectives are mainly focussed in the optimization, of the already described techniques to gain in sensitivity and sensibility and in the development of new molecular biology techniques (quantitative real time PCRs), that are faster and easier to apply and that allow a positive diagnosis even in early stages of infection. However, molecular tools detect DNA sequences of the pathogen which does not imply that pathogen is viable in the cell host and the infection is established. Consequently, it needs to be validated against other techniques, such as histology or in situ hybridization, so that its reliability can be determinedAuthors want to thanks the Ministerio de Agricultura, Alimentacion y Medio Ambiente, to CSIC (project 201640E024) and to Ministerio de Economía y competitividad (project AGL2015-65705-R) for their financial supportPeer reviewe

    Desarrollo del sentido numérico y los vínculos con el rendimiento escolar en aritmética

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    Se propone una investigación estructurada en cuatro fases sobre el rendimiento escolar en aritmética y sus vínculos con el desarrollo del sentido numérico. La muestra esta integrada por 16 profesores y 32 estudiantes de educación primaria que laboran y estudian en el Distrito Federal. Este trabajo investiga la relación entre el desarrollo del sentido numérico y el rendimiento escolar en aritmética en dos direcciones: (I) Seguimiento de un ciclo escolar a 2 grupos de estudiantes de 3º y 6º año de educación primaria caracterizados por sus profesores como: grupo 1 “exitosos en matemáticas” y grupo 2 “no exitosos o que tienden al fracaso en matemáticas”, y (II) La Identificación de las actividades centradas en el desarrollo del sentido numérico por parte de los docentes. En este documento se alude a los avances correspondientes de la tercer fase de la investigación

    De las opiniones a los argumentos

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    La actividad consiste en inferir la definición del término "light" a partir de productos así etiquetados y de otros estándar. Pero en las primeras respuestas pesan mucho más los supuestos que los datos que proporcionan esos envases. Lo que se pretende precisamente es que los alumnos y alumnas aprendan a distinguir las opiniones de los argumentos, a cuestionarse lo que dan por hecho y a desarrollar razonamientos claros y precisos

    A Status Assessment of Perkinsiosis, Bonamiosis, and Mateiliosis in Commercial Marine Bivalves from Southern Brazil

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    14 páginas, 1 figura, 3 tablas.-- Simone Sühnel ... et al.The protozoans Perkinsus marinus, Perkinsus olseni, Bonamia ostreae, Bonamia exitiosa, and Marteilia refringens are responsible for some of the most detrimental diseases in the production of cultivated shellfish worldwide and are classified as notifiable diseases by the World Organization for Animal Health (OIE). This study examined the general health status of wild and cultured bivalves from southern Brazil and included diagnostic tests for the presence of Perkinsus sp., Bonamia sp., andMarteilia sp. Cultured bivalves included the mangrove oyster Crassostrea gasar (syn. Crassostrea brasiliana), the brown mussel Perna perna, the lion's paw scallop Nodipecten nodosus, andwing pearl oyster Pteria hirundo. Themangrove oyster Crassostrea rhizophorae and the carib pointed venus clam Anomalocardia brasiliana (syn. Anomalocardia flexuosa) were collected from wild populations. A variety of parasitic or commensal organisms were detected by histology including Ancistrocoma-like and Spenophrya-like organisms; Bucephalus genus, Nematopsis sp., Steinhausia sp., and Tylocephalum sp.; unidentified trematode; unknown protozoan and metazoans; and an amoeba parasite. Hemocytic infiltration was most commonly associated with parasitized animals. Histological, culture and molecular diagnostic tests did not find any evidence of the presence of OIE-listed pathogens or related species in this study. Although the current survey did not identify any pathogens or diseases of concern, it provides baseline health assessment data for these species against which any future disease developments or significant changes in population health can be compared. These data are also valuable with respect to the development and implementation of public policies related to aquatic animal healthWe would like to thank to the Ministry of Fisheries and Aquaculture, Brazil, for the research support provided to the Fundaçao de Amparo à Pesquisa do Estado de Santa Catarina (FAPESC), Brazil; the National Council of Technological and ScientificDevelopment, Brazil (CNPq-558222/2008-0), for supporting themacro- andmicroscopical analysis and for providing a grant (CNPq-301072/2007-8); the Coordenaçao de Aperfeiçoamento de Pessoal de Nivel Superior (CAPES), Brazil, for post-doctoral scholarship support for SS; the Pacific Biologic Station and Vancouver Island University (VIU) in Canada for supporting the molecular studiesPeer reviewe

    Co-occurrence and diversity patterns of benthonic and planktonic communities in a shallow marine ecosystem

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    Marine microorganisms are involved in a variety of biogeochemical cycles and live in diverse ecological communities where they interact with each other and with other organisms to guarantee ecosystem functions. The present study focused on a shallow marine environment located in Ría de Vigo (NW, Spain), where sediment and size-fractionated plankton samples were collected from 2016 to 2018. DNA metabarcoding was used to describe the eukaryote and prokaryote composition and diversity in sediments and plankton and to depict possible associations among the most frequent and abundant organisms by co-occurrence network analysis. High eukaryote and prokaryote diversity indices were obtained in all compartments. Significant differences among eukaryote and prokaryote communities were found between sediment and plankton samples, with a high percentage of exclusive operational taxonomic units (OTUs) associated with each compartment, especially from sediment. Despite these differences, shared taxa between water and sediment were also obtained, suggesting a relatively meaningful exchange of organisms between both environmental compartments. Significant co-occurrences were mainly obtained between prokaryotes (41%), followed by eukaryotes–prokaryotes (32%) and between eukaryotes (27%). The abundant and strong positive correlations between organisms, including representatives from the sediment and the water column, suggested an essential role of biotic interactions as community-structuring factors in shallow waters where beneficial associations likely prevail. This study provides a novel approach for the detailed description of the eukaryote and prokaryote diversity and co-occurrence patterns in a shallow marine area, including both the sediment and different water-size fractions. The high diversity obtained and the detection of predominantly coexisting interactions among organisms from sediment and the overlying water column suggest a movement of species between both habitats and therefore confirm the importance of integratively studying shallow marine ecosystems.Xunta de Galicia | Ref. IN606A-2018/020Xunta de Galicia | Ref. IN607B 2019/01Agencia Estatal de Investigación | Ref. CTM2017-83362-RInterreg España-Portugal | Ref. 20200474_BLUEBIOLA

    Nodular Mucinosis of the Breast in a Male : Reassessment of Diagnostic Criteria and Proposal for Its Classification as a Soft Tissue Tumor in the Myofibroblastoma and Spindle Cell Lipoma Spectrum

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    Nodular mucinosis of the breast (NMB) is a rare entity with only a few cases described in the literature, most of them in young girls. All cases are located in the nipple and areolar area and microscopically consist of a multinodular myxoid mesenchymal proliferation. Bands of sclerotic collagen containing preexisting breast ducts and abundant vascularization are other features typical of NMB. No relation to Carney complex has been reported, and an indolent behavior is the rule in all patients. We present a case of NMB occurring in the nipple of a 46-year-old man and analyze the clinicopathological features of the other cases of NMB reported in the English literature, concluding that two of them most likely correspond to trauma-induced cutaneous focal mucinosis of the mammary areola. Finally, we review diagnostic criteria for NMB and elaborate an ontogenetic hypothesis based on both its morphological resemblance to myofibroblastoma and its immunohistochemical profile

    3D-printed PLA medical devices: physicochemical changes and biological response after sterilisation treatments

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    Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGPolylactic acid (PLA) has become one of the most commonly used polymers in medical devices given its biocompatible, biodegradable and bioabsorbable properties. In addition, due to PLA’s thermoplastic behaviour, these medical devices are now obtained using 3D printing technologies. Once obtained, the 3D-printed PLA devices undergo different sterilisation procedures, which are essential to prevent infections. This work was an in-depth study of the physicochemical changes caused by novel and conventional sterilisation techniques on 3D-printed PLA and their impact on the biological response in terms of toxicity. The 3D-printed PLA physicochemical (XPS, FTIR, DSC, XRD) and mechanical properties as well as the hydrophilic degree were evaluated after sterilisation using saturated steam (SS), low temperature steam with formaldehyde (LTSF), gamma irradiation (GR), hydrogen peroxide gas plasma (HPGP) and CO2 under critical conditions (SCCO). The biological response was tested in vitro (fibroblasts NCTC-929) and in vivo (embryos and larvae wild-type zebrafish Danio rerio). The results indicated that after GR sterilisation, PLA preserved the O:C ratio and the semi-crystalline structure. Significant changes in the polymer surface were found after HPGP, LTSF and SS sterilisations, with a decrease in the O:C ratio. Moreover, the FTIR, DSC and XRD analysis revealed PLA crystallisation after SS sterilisation, with a 52.9% increase in the crystallinity index. This structural change was also reflected in the mechanical properties and wettability. An increase in crystallinity was also observed after SCCO and LTSF sterilisations, although to a lesser extent. Despite these changes, the biological evaluation revealed that none of the techniques were shown to promote the release of toxic compounds or PLA modifications with toxicity effects. GR sterilisation was concluded as the least reactive technique with good perspectives in the biological response, not only at the level of toxicity but at all levels, since the 3D-printed PLA remained almost unaltered.POCTEP INTERREG España- Portugal | Ref. BLUEBIOLABInterreg Atlantic Area | Ref. BLUEHUMAN EAPA_151/2016Ministerio de Ciencia e Innovación | Ref. PID 2020-115415RB-100Xunta de Galicia | Ref. ED431C 2021/49Xunta de Galicia | Ref. ED481A 2019/314Xunta de Galicia | Ref. IN606A-2017/011Fundação para a Ciência e a Tecnologia | Ref. UIDB/50016/202

    Scrapie infectivity is quickly cleared in tissues of orally-infected farmed fish

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    BACKGROUND: Scrapie and bovine spongiform encephalopathy (BSE) belongs to the group of animal transmissible spongiform encephalopathy (TSE). BSE epidemic in the UK and elsewhere in Europe has been linked to the use of bovine meat and bone meals (MBM) in the feeding of cattle. There is concern that pigs, poultry and fish bred for human consumption and fed with infected MBM would eventually develop BSE or carry residual infectivity without disease. Although there has been no evidence of infection in these species, experimental data on the susceptibility to the BSE agent of farm animals other than sheep and cow are limited only to pigs and domestic chicken. In the framework of a EU-granted project we have challenged two species of fish largely used in human food consumption, rainbow trout (Oncorhynchus mykiss) and turbot (Scophthalmus maximus), with a mouse-adapted TSE strain (scrapie 139A), to assess the risk related to oral consumption of TSE contaminated food. In trout, we also checked the "in vitro" ability of the pathological isoform of the mouse prion protein (PrP(Sc)) to cross the intestinal epithelium when added to the mucosal side of everted intestine. RESULTS: Fish challenged with a large amount of scrapie mouse brain homogenate by either oral or parenteral routes, showed the ability to clear the majority of infectivity load. None of the fish tissues taken at different time points after oral or parenteral inoculation was able to provoke scrapie disease after intracerebral inoculation in recipient mice. However, a few recipient mice were positive for PrP(Sc )and spongiform lesions in the brain. We also showed a specific binding of PrP(Sc )to the mucosal side of fish intestine in the absence of an active uptake of the prion protein through the intestinal wall. CONCLUSION: These results indicate that scrapie 139A, and possibly BSE, is quickly removed from fish tissues despite evidence of a prion like protein in fish and of a specific binding of PrP(Sc )to the mucosal side of fish intestine

    INTERGROWTH-21st versus a customized method for the prediction of neonatal nutritional status in hypertensive disorders of pregnancy

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    Background Hypertensive disorders of pregnancy (HDP) generate complications and are one of the principal causes of maternal, foetal, and neonatal mortality worldwide. It has been observed that in pregnancies with HDP, the incidence of foetuses small for their gestational age (SGA) is twice as high as that in noncomplicated pregnancies. In women with HDP, the identification of foetuses (SGA) is substantially important, as management and follow-up are determined by this information. Objective The objective of this study was to evaluate whether the INTERGROWTH-21st method or customized birthweight references better identify newborns with an abnormal nutritional status resulting from HDP. Method A comparative analysis study was designed with two diagnostic methods for the prediction of neonatal nutritional status in pregnancies with HDP. The performance of both methods in identifying neonatal malnutrition (defined by a neonatal body mass index < 10(th) centile or a ponderal index < 10(th) centile) was assessed by calculating sensitivity, specificity, positive predictive value, negative predictive value, diagnostic odds ratio, Youden's index and probability ratios. Results The study included 226 pregnant women diagnosed with HDP. The customized method identified 45 foetuses as small for gestational age (19.9%), while the INTERGROWTH-21st method identified 27 newborns with SGA (11.9%). The difference between proportions was statistically significant (p < 0.01). Using body mass index (< 10(th) centile) as a measure of nutritional status, newborns identified as SGA by the customized method showed a higher risk of malnutrition than those identified as SGA by INTERGROWTH-21st (RR: 4.87 (95% CI: 1.86-12.77) vs. 3.75 (95% CI: 1.49-9.43)) (DOR: 5.56 (95% CI: 1.82-16.98) vs. 4.84 (95% CI: 1.51-15.54)) Even when using Ponderal index (< 10(th) centile), newborns identified as SGA by the customized method showed a higher risk of malnutrition than those identified as SGA by INTERGROWTH-21st (RR 2.37 (95% CI: 1.11-5.05) vs. 1.68 (95% CI: 0.70-4.03))(DOR 2.62 (95% CI: 1.00-6.87) vs. 1.90 (95% CI: 0.61-5.92)). Conclusion In pregnant women with HDP, the predictive ability of the customized foetal growth curves to identify neonatal malnutrition appears to surpass that of INTERGROWTH-21st

    Development and validation of a multivariable prediction model of spontaneous preterm delivery and microbial invasion of the amniotic cavity in women with preterm labor

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    BACKGROUND: Early spontaneous preterm delivery is often associ- ated with microbial invasion of the amniotic cavity and/or intraamniotic inflammation. OBJECTIVE: The objective of the study was to develop and validate clinically feasible multivariable prediction models of spontaneous delivery within 7 days and microbial invasion of the amniotic cavity in women admitted with diagnose of preterm labor and intact membranes below 34 weeks. STUDY DESIGN: We used data from a cohort of women admitted from 2012 to 2018 with diagnosis of preterm labor below 34 weeks who had undergone amniocentesis to rule out microbial invasion of the amniotic cavity. The main outcome was spontaneous delivery within 7 days from admission. The secondary outcome was microbial invasion of the amniotic cavity, defined by a positive culture and/or 16S ribosomal RNA gene in the amniotic fluid. The sample (n 1⁄4 358) was divided into derivation (2012e2016) and validation cohorts (2017e2018). Logistic regression models using a stepwise selection of variables were developed for the outcomes evaluated. We explored as predictive variables ultrasound cervical length measurement at admission, maternal C-reactive protein, gestational age, amniotic fluid glucose, and interleukin-6 (expressed as log units). Models were developed in the derivation cohort and applied to the validation cohort and diagnostic performance was calculated. RESULTS: The derivation cohort included 263 women and the valida- tion cohort 95 women. One hundred five of the women (39%, 105 of 268) spontaneously delivered in the following 7 days and 68 (19%, 68 of 358) had microbial invasion of the amniotic cavity. For spontaneous delivery within 7 days after admission, 4 predictors were identified: cervical length at admission, gestational age, amniotic fluid glucose, and interleukin-6. The diagnostic performance of the model was assessed in the validation cohort using the receiver operating characteristic curve and showed an area under curve of 0.86 (95% confidence interval, 0.77e0.95) with a detection rate of spontaneous delivery within 7 days of 87%, a false- positive rate of 33%, a negative predictive value of 80%, and a negative likelihood ratio of 0.1908. For microbial invasion of the amniotic cavity, 2 independent predictors of the amniotic cavity were identified: amniotic fluid glucose and maternal C-reactive protein. The receiver operating characteristic curve and an area under curve in the validation cohort was 0.83 (95% confidence interval, 0.70e0.96) with a detection rate of 76%, a false-positive rate of 8%, a negative predictive value of 93%, and a negative likelihood ratio of 0.2591. CONCLUSION: In women with preterm labor, we propose 2 clinically feasible prediction models to classify as low vs high risk of spontaneous delivery within 7 days and of microbial invasion of the amniotic cavity. The models showed a high diagnostic performance and could be of value to optimize clinical management
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