597 research outputs found

    Understanding the differential hygienic behavior towards drone brood in Apis mellifera colonies from Argentina

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    Brood diseases of Apis mellifera colonies constitute a main problem of beekeeping worldwide. Worker bees display a social health mechanism that consists in detecting, uncapping and removing dead or diseased brood from the hive: the hygienic behavior (CH). These activities are induced by olfactory cues and have been described as associated to hygiene of brood parasitized by Varroa destructor. This mite have preference for drone brood, but the efficiency of CH towards their cells is significantly lower compared with cells of worker brood, being left uninspected by workers. Some authors suggest that a possible cause of the CH differences is due to the cell wax cap of drone brood (thicker than worker cells) acting as a barrier to volatile compounds and obstructing disease detection. The aims of this research were to study the differential CH towards worker and drone brood belonging to highly hygienic colonies from Argentina, and to explore the importance of drone cell wax cap as an interfering factor in the transmission of chemical signals. To this end, removal percentages of pin-killed worker and drone brood were recorded and an innovative cell wax cap exchange was implemented in three different treatments: pin-killed worker pupa with a healthy drone cell wax cap; a healthy worker pupa with a pin-killed drone cell wax cap; and a healthy worker pupa covered with a healthy drone cell wax cap (control). Results showed a greater removal towards worker cells than drone cells. For the cell wax cap exchange experiment, we found that the removal of pin-killed worker pupae covered with healthy drone cell wax cap was significantly high, while the removal of healthy worker pupae covered with pin-killed drone opercula was low. These preliminary results confirms a differential behavior between both type of brood cells and suggests that the cell wax cap of drone brood is not interfering the detection of chemical compounds from the diseased brood by worker bees, regardless the thickness. This work contributes to a better understanding of the detection activity of different types of diseased brood and provides information useful to control strategies of varroosis and other brood diseases.Fil: Dowd, D. Duggan. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Muntaabski, Irina. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Agrobiotecnologia y Biologia Molecular. Grupo Vinculado Instituto de Genetica "ewald A. Favret" Al Iabimo | Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Agrobiotecnologia y Biologia Molecular. Grupo Vinculado Instituto de Genetica "ewald A. Favret" Al Iabimo.; ArgentinaFil: Russo, R. M.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Landi, L.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; ArgentinaFil: Lanzavecchia, S. B.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Cladera, J. L.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Palacio, M. A.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Bedascarrabure, E.. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion de Agroindustria. Instituto de Ingeniería Rural.; ArgentinaFil: Scannapieco, Alejandra Carla. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Agrobiotecnologia y Biologia Molecular. Grupo Vinculado Instituto de Genetica "ewald A. Favret" Al Iabimo | Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Agrobiotecnologia y Biologia Molecular. Grupo Vinculado Instituto de Genetica "ewald A. Favret" Al Iabimo.; ArgentinaFil: Liendo, María Clara. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Agrobiotecnologia y Biologia Molecular. Grupo Vinculado Instituto de Genetica "ewald A. Favret" Al Iabimo | Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Agrobiotecnologia y Biologia Molecular. Grupo Vinculado Instituto de Genetica "ewald A. Favret" Al Iabimo.; Argentina46th Apimondia International Apicultural Congress: Beekeeping together within agricultureQuébecCanadáInternational Federation of Beekeepers' AssociationsCanadian Honey Counci

    Development and analysis of a model based on chirped fiber Bragg gratings employed for cracks characterization in materials

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    In this work a model was developed that allows to understand the behavior of a chirped fiber Bragg grating for the detection and characterization of cracks in materials. In addition to the amplitude response, we show that the group delay of the grating provides useful information for the characterization of the crack. The position of the crack can be determined thanks to the linear chirp of the grating that fixes a correlation between the spatial position and both, the wavelength and the group delay. However, our analysis shows that this simple approach has a source of error, which can be overcome if a controllable external strain can be applied to the embedded grating, additional to the strain generated by the embedding process. Thus, the width of the crack can be also estimated. The effect of the appearance of a crack on the grating generates simple o multiple transmission peaks that are analyzed considering the behavior of a Fabry–Perot fiber cavity. This simple model was experimentally tested and preliminary results were in good agreement with the simulations.Centro de Investigaciones Óptica

    AD8-Argentina questionnaire to detect dementia in primary health care

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    Memory complaint may be very common in elderly people over 65, but also is present in early stage of dementing processes. Instruments to detect dementia in primary health care must be easy and quickly to be applied. In 2005, Galvin et al. developed a questionnaire Alzheimer's Disease 8 (AD8) which was based on a brief interview with and informant to detect subjects with dementia. The objective of this work was to perform the translation, adaptation to the Spanish language near the Rio de la Plata and to establish the validity, reliability and discriminative proprieties of AD8-arg for use in primary care. Methods 18 patients with dementia of Alzheimer type, 25 with mild cognitive impairment and 19 normal controls matched by age and education were assessed with the AD8-arg and an extensive neuropsychological battery. Concurrent validity was strong with significant correlation with MMSE (-0,464: P<0.001) and CDR (0,514; P<0.001). Internal consistency was adequate correlating with all cognitive tests. The area under the ROC curve was 0.89 and a cutoff score of 2 had a sensitivity of 0.80 and specificity of 0.83 showing excellent discrimination between demented and non-demented patients. The AD8-arg is a tool for quick and easy administration with adequate psychometric properties for use in screening of dementia in primary care in our region.Existe una gran cantidad de personas mayores de 65 años que consultan por falta de memoria, la cual puede ser muy frecuente en el curso del envejecimiento normal, pero también está en las etapas iniciales de procesos demenciales. Debido a esto, se debe contar con instrumentos de detección de estas enfermedades que puedan ser aplicados de manera fácil y rápida en espacios de Atención Primaria de la salud. En el año 2005, Galvin et al. desarrollaron el cuestionario Alzheimer Disease 8 (AD8), el cual está basado en una breve entrevista a un informante para detectar sujetos con demencia. El objetivo del presente trabajo es realizar la adaptación al español rioplatense y validación de este instrumento (AD8-arg) para ser utilizado en asistencia primaria. Fueron evaluados con este instrumento y con una extensa batería cognitiva 18 pacientes con demencia tipo Alzheimer, 25 con deterioro cognitivo leve y 19 controles normales apareados por edad y escolaridad. El AD8-arg tuvo una alta validez convergente con una significativa correlación con el MMSE (–0,464; p < 0,001) y el CDR (0,514; p < 0,001). La consistencia interna fue adecuada correlacionando con todas las pruebas cognitivas. El área bajo la curva ROC del cuestionario fue 0,89 y con un puntaje de corte de 2 tuvo una sensibilidad 0,80 y una especificidad de 0,83 para detectar demencias. El AD8-arg es un instrumento de rápida y fácil administración con adecuadas propiedades psicométricas para ser usado en detección de demencia en asistencia primaria en nuestro medio

    Obstetric history and mammographic density: a population-based cross-sectional study in Spain (DDM-Spain)

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    High mammographic density (MD) is used as a phenotype risk marker for developing breast cancer. During pregnancy and lactation the breast attains full development, with a cellular-proliferation followed by a lobular-differentiation stage. This study investigates the influence of obstetric factors on MD among pre- and post-menopausal women. We enrolled 3,574 women aged 45–68 years who were participating in breast cancer screening programmes in seven screening centers. To measure MD, blind anonymous readings were taken by an experienced radiologist, using craniocaudal mammography and Boyd’s semiquantitative scale. Demographic and reproductive data were directly surveyed by purpose-trained staff at the date of screening. The association between MD and obstetric variables was quantified by ordinal logistic regression, with screening centre introduced as a random effect term. We adjusted for age, number of children and body mass index, and stratified by menopausal status. Parity was inversely associated with density, the probability of having high MD decreased by 16% for each new birth (P value < 0.001). Among parous women, a positive association was detected with duration of lactation [>9 months: odds ratio (OR) = 1.33; 95% confidence interval (CI) = 1.02–1.72] and weight of first child (>3,500 g: OR = 1.32; 95% CI = 1.12–1.54). Age at first birth showed a different effect in pre- and post-menopausal women (P value for interaction = 0.030). No association was found among pre-menopausal women. However, in post-menopausal women the probability of having high MD increased in women who had their first child after the age of 30 (OR = 1.53; 95% CI = 1.17–2.00). A higher risk associated with birth of twins was also mainly observed in post-menopausal women (OR = 2.02; 95% CI = 1.18–3.46). Our study shows a greater prevalence of high MD in mothers of advanced age at first birth, those who had twins, those who have breastfed for longer periods, and mothers whose first child had an elevated birth weight. These results suggest the influence of hormones and growth factors over the proliferative activity of the mammary gland

    Human Macrophages and Dendritic Cells Can Equally Present MART-1 Antigen to CD8+ T Cells after Phagocytosis of Gamma-Irradiated Melanoma Cells

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    Dendritic cells (DC) can achieve cross-presentation of naturally-occurring tumor-associated antigens after phagocytosis and processing of dying tumor cells. They have been used in different clinical settings to vaccinate cancer patients. We have previously used gamma-irradiated MART-1 expressing melanoma cells as a source of antigens to vaccinate melanoma patients by injecting irradiated cells with BCG and GM-CSF or to load immature DC and use them as a vaccine. Other clinical trials have used IFN-gamma activated macrophage killer cells (MAK) to treat cancer patients. However, the clinical use of MAK has been based on their direct tumoricidal activity rather than on their ability to act as antigen-presenting cells to stimulate an adaptive antitumor response. Thus, in the present work, we compared the fate of MART-1 after phagocytosis of gamma-irradiated cells by clinical grade DC or MAK as well as the ability of these cells to cross present MART-1 to CD8+ T cells. Using a high affinity antibody against MART-1, 2A9, which specifically stains melanoma tumors, melanoma cell lines and normal melanocytes, the expression level of MART-1 in melanoma cell lines could be related to their ability to stimulate IFN-gamma production by a MART-1 specific HLA-A*0201-restricted CD8+ T cell clone. Confocal microscopy with Alexa Fluor®647-labelled 2A9 also showed that MART-1 could be detected in tumor cells attached and/or fused to phagocytes and even inside these cells as early as 1 h and up to 24 h or 48 h after initiation of co-cultures between gamma-irradiated melanoma cells and MAK or DC, respectively. Interestingly, MART-1 was cross-presented to MART-1 specific T cells by both MAK and DC co-cultured with melanoma gamma-irradiated cells for different time-points. Thus, naturally occurring MART-1 melanoma antigen can be taken-up from dying melanoma cells into DC or MAK and both cell types can induce specific CD8+ T cell cross-presentation thereafter

    Relationship between tobacco, cagA and vacA i1 virulence factors and bacterial load in patients infected by Helicobacter pylori

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    Background and Aim Several biological and epidemiological studies support a relationship between smoking and Helicobacter pylori (H. pylori) to increase the risk of pathology. However, there have been few studies on the potential synergistic association between specific cagA and vacA virulence factors and smoking in patients infected by Helicobacter pylori. We studied the relationship between smoking and cagA, vacA i1 virulence factors and bacterial load in H. pylori infected patients. Methods Biopsies of the gastric corpus and antrum from 155 consecutive patients in whom there was clinical suspicion of infection by H. pylori were processed. In 106 patients H. pylori infection was detected. Molecular methods were used to quantify the number of microorganisms and presence of cagA and vacA i1 genes. A standardized questionnaire was used to obtain patients’ clinical data and lifestyle variables, including tobacco and alcohol consumption. Adjusted Odds Ratios (ORadjusted) were estimated by unconditional logistic regression. Results cagA was significantly associated with active-smoking at endoscope: ORadjusted 4.52. Evidence of association was found for vacA i1 (ORadjusted 3.15). Bacterial load was higher in active-smokers, although these differences did not yield statistical significance (median of 262.2 versus 79.4 copies of H. pylori per cell). Conclusions The association between smoking and a higher risk of being infected by a virulent bacterial population and with higher bacterial load, support a complex interaction between H. pylori infection and environmental factors

    Association Patterns in Saproxylic Insect Networks in Three Iberian Mediterranean Woodlands and Their Resistance to Microhabitat Loss

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    The assessment of the relationship between species diversity, species interactions and environmental characteristics is indispensable for understanding network architecture and ecological distribution in complex networks. Saproxylic insect communities inhabiting tree hollow microhabitats within Mediterranean woodlands are highly dependent on woodland configuration and on microhabitat supply they harbor, so can be studied under the network analysis perspective. We assessed the differences in interacting patterns according to woodland site, and analysed the importance of functional species in modelling network architecture. We then evaluated their implications for saproxylic assemblages’ persistence, through simulations of three possible scenarios of loss of tree hollow microhabitat. Tree hollow-saproxylic insect networks per woodland site presented a significant nested pattern. Those woodlands with higher complexity of tree individuals and tree hollow microhabitats also housed higher species/interactions diversity and complexity of saproxylic networks, and exhibited a higher degree of nestedness, suggesting that a higher woodland complexity positively influences saproxylic diversity and interaction complexity, thus determining higher degree of nestedness. Moreover, the number of insects acting as key interconnectors (nodes falling into the core region, using core/periphery tests) was similar among woodland sites, but the species identity varied on each. Such differences in insect core composition among woodland sites suggest the functional role they depict at woodland scale. Tree hollows acting as core corresponded with large tree hollows near the ground and simultaneously housing various breeding microsites, whereas core insects were species mediating relevant ecological interactions within saproxylic communities, e.g. predation, competitive or facilitation interactions. Differences in network patterns and tree hollow characteristics among woodland sites clearly defined different sensitivity to microhabitat loss, and higher saproxylic diversity and woodland complexity showed positive relation with robustness. These results highlight that woodland complexity goes hand in hand with biotic and ecological complexity of saproxylic networks, and together exhibited positive effects on network robustness.The research Projects I+D CGL2011-23658 y CGL2012-31669 of the Spanish Minister of Science provided economic support

    Pathogenetics of alveolar capillary dysplasia with misalignment of pulmonary veins.

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    Alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) is a lethal lung developmental disorder caused by heterozygous point mutations or genomic deletion copy-number variants (CNVs) of FOXF1 or its upstream enhancer involving fetal lung-expressed long noncoding RNA genes LINC01081 and LINC01082. Using custom-designed array comparative genomic hybridization, Sanger sequencing, whole exome sequencing (WES), and bioinformatic analyses, we studied 22 new unrelated families (20 postnatal and two prenatal) with clinically diagnosed ACDMPV. We describe novel deletion CNVs at the FOXF1 locus in 13 unrelated ACDMPV patients. Together with the previously reported cases, all 31 genomic deletions in 16q24.1, pathogenic for ACDMPV, for which parental origin was determined, arose de novo with 30 of them occurring on the maternally inherited chromosome 16, strongly implicating genomic imprinting of the FOXF1 locus in human lungs. Surprisingly, we have also identified four ACDMPV families with the pathogenic variants in the FOXF1 locus that arose on paternal chromosome 16. Interestingly, a combination of the severe cardiac defects, including hypoplastic left heart, and single umbilical artery were observed only in children with deletion CNVs involving FOXF1 and its upstream enhancer. Our data demonstrate that genomic imprinting at 16q24.1 plays an important role in variable ACDMPV manifestation likely through long-range regulation of FOXF1 expression, and may be also responsible for key phenotypic features of maternal uniparental disomy 16. Moreover, in one family, WES revealed a de novo missense variant in ESRP1, potentially implicating FGF signaling in the etiology of ACDMPV

    Repositioning of the global epicentre of non-optimal cholesterol

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    High blood cholesterol is typically considered a feature of wealthy western countries(1,2). However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world(3) and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health(4,5). However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol-which is a marker of cardiovascular riskchanged from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million-4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.Peer reviewe
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