45 research outputs found

    Enhanced detection of viral RNA species using fokI-assisted digestion of DNA duplexes and DNA/RNA hybrids

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    The accurate detection of nucleic acids from certain biological pathogens is critical for the diagnosis of human diseases. However, amplified detection of RNA molecules from a complex sample by direct detection of RNA/DNA hybrids remains a challenge. Here, we show that type IIS endonuclease FokI is able to digest DNA duplexes and DNA/RNA hybrids when assisted by a dumbbell-like fluorescent sensing oligonucleotide. As proof of concept, we designed a battery of sensing oligonucleotides against specific regions of the SARS-CoV-2 genome and interrogated the role of FokI relaxation as a potential nicking enzyme for fluorescence signal amplification. FokI-assisted digestion of SARS-CoV-2 probes increases the detection signal of ssDNA and RNA molecules and decreases the limit of detection more than 3.5-fold as compared to conventional molecular beacon approaches. This cleavage reaction is highly specific to its target molecules, and no detection of other highly related B-coronaviruses was observed in the presence of complex RNA mixtures. In addition, the FokI-assisted reaction has a high multiplexing potential, as the combined detection of different viral RNAs, including different SARS-CoV-2 variants, was achieved in the presence of multiple combinations of fluorophores and sensing oligonucleotides. When combined with isothermal rolling circle amplification technologies, FokI-assisted digestion reduced the detection time of SARS-CoV-2 in COVID-19-positive human samples with adequate sensitivity and specificity compared to conventional reverse transcription polymerase chain reaction approaches, highlighting the potential of FokI-assisted signal amplification as a valuable sensing mechanism for the detection of human pathogens.Funding was provided by the ISCIII (COV00624 to J.R.T. andM.F.F., PI18/01527 and PI21/01067 to M.F.F.), CSIC (202020E092 to M.F.F), the European Commission NextGenerationEU, through CSIC’s Global Health Platform (PTI Salud Global) and the Spanish Ministry of Science and Innovation through the Recovery, Transformation and Resilience Plan (GL2021-03-39 and GL2021-03-040), the PCTI from the Asturias Government, co-funded by 2018−2022/FEDER (IDI/2018/146 to M.F.F.), the AECC (PROYE18061FERN to M.F.F), ISPA-Janssen (048-Intramural Nov-Tevar to J.R.T.) and the IUOPA. J.R.T is supported by a JdC fellowship from the Spanish Ministry of Science and Innovation (IJC2018-36825-I). R.F.P. and P.S.O. are supported by the Severo Ochoa program (BP17-114 and BP17-165). A.P. is supported by the PFIS program (ISCIII, FI19/ 00085). J.J.A.L. is supported by the AECC fellowship. C.M. and V.L. are supported by IUOPA, and R.G.U. is supported by CIBERER.Peer reviewe

    Project goals, target selection, and stellar characterization

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    The detection of habitable worlds is one of humanitya-s greatest endeavors. Thus far, astrobiological studies have shown that one of the most critical components for allowing life to develop is liquid water. Its chemical properties and its capacity to dissolve and, hence, transport other substances makes this constituent a key piece in this regard. As a consequence, looking for life as we know it is directly related to the search for liquid water. For a remote detection of life in distant planetary systems, this essentially means looking for planets in the so-called habitable zone. In this sense, K-dwarf stars are the perfect hosts to search for planets in this range of distances. Contrary to G-dwarfs, the habitable zone is closer, thus making planet detection easier using transit or radial velocity techniques. Contrary to M-dwarfs, stellar activity is on a much smaller scale, hence, it has a smaller impact in terms of both the detectability and the true habitability of the planet. Also, K-dwarfs are the quietest in terms of oscillations, and granulation noise. In spite of this, there is a dearth of planets in the habitable zone of K-dwarfs due to a lack of observing programs devoted to this parameter space. In response to a call for legacy programs of the Calar Alto observatory, we have initiated the first dedicated and systematic search for habitable planets around these stars: K-dwarfs Orbited By habitable Exoplanets (KOBE). This survey is monitoring the radial velocity of 50 carefully pre-selected K-dwarfs with the CARMENES instrument over five semesters, with an average of 90 data points per target. Based on planet occurrence rates convolved with our detectability limits, we expect to find 1.68 ± 0.25 planets per star in the KOBE sample. Furthermore, in half of the sample, we expect to find one of those planets within the habitable zone. Here, we describe the motivations, goals, and target selection for the project as well as the preliminary stellar characterization. © 2022 EDP Sciences. All rights reserved

    The Tree Biodiversity Network (BIOTREE-NET): prospects for biodiversity research and conservation in the Neotropics

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    Biodiversity research and conservation efforts in the tropics are hindered by the lack of knowledge of the assemblages found there, with many species undescribed or poorly known. Our initiative, the Tree Biodiversity Network (BIOTREE-NET), aims to address this problem by assembling georeferenced data from a wide range of sources, making these data easily accessible and easily queried, and promoting data sharing. The database (GIVD ID NA-00-002) currently comprises ca. 50,000 tree records of ca. 5,000 species (230 in the IUCN Red List) from \u3e2,000 forest plots in 11 countries. The focus is on trees because of their pivotal role in tropical forest ecosystems (which contain most of the world\u27s biodiversity) in terms of ecosystem function, carbon storage and effects on other species. BIOTREE-NET currently focuses on southern Mexico and Central America, but we aim to expand coverage to other parts of tropical America. The database is relational, comprising 12 linked data tables. We summarise its structure and contents. Key tables contain data on forest plots (including size, location and date(s) sampled), individual trees (including diameter, when available, and both recorded and standardised species name), species (including biological traits of each species) and the researchers who collected the data. Many types of queries are facilitated and species distribution modelling is enabled. Examining the data in BIOTREE-NET to date, we found an uneven distribution of data in space and across biomes, reflecting the general state of knowledge of the tropics. More than 90% of the data were collected since 1990 and plot size varies widely, but with most less than one hectare in size. A wide range of minimum sizes is used to define a \u27tree\u27. The database helps to identify gaps that need filling by further data collection and collation. The data can be publicly accessed through a web application at http://portal.biotreenet.com. Researchers are invited and encouraged to contribute data to BIOTREE-NET

    Impact of COVID-19 Lockdown in Eating Disorders: A Multicentre Collaborative International Study

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    Background. The COVID-19 lockdown has had a significant impact on mental health. Patients with eating disorders (ED) have been particularly vulnerable. Aims. (1) To explore changes in eating-related symptoms and general psychopathology during lockdown in patients with an ED from various European and Asian countries; and (2) to assess differences related to diagnostic ED subtypes, age, and geography. Methods. The sample comprised 829 participants, diagnosed with an ED according to DSM-5 criteria from specialized ED units in Europe and Asia. Participants were assessed using the COVID-19 Isolation Scale (CIES). Results. Patients with binge eating disorder (BED) experienced the highest impact on weight and ED symptoms in comparison with other ED subtypes during lockdown, whereas individuals with other specified feeding and eating disorders (OFSED) had greater deterioration in general psychological functioning than subjects with other ED subtypes. Finally, Asian and younger individuals appeared to be more resilient. Conclusions. The psychopathological changes in ED patients during the COVID-19 lockdown varied by cultural context and individual variation in age and ED diagnosis. Clinical services may need to target preventive measures and adapt therapeutic approaches for the most vulnerable patients

    La Red Internacional de Inventarios Forestales (BIOTREE-NET) en Mesoamérica: avances, retos y perspectivas futuras

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    Conservation efforts in Neotropical regions are often hindered by lack of data, since for many species there is a vacuum of information, and many species have not even been described yet. The International Network of Forest Inventory Plots (BIOTREE-NET) gathers and facilitates access to tree data from forest inventory plots in Mesoamerica, while encouraging data exchange between researchers, managers and conservationists. The information is organised and standardised into a single database that includes spatially explicit data. This article describes the scope and objectives of the network, its progress, and the challenges and future perspectives. The database includes above 50000 tree records of over 5000 species from more than 2000 plots distributed from southern Mexico through to Panama. Information is heterogeneous, both in nature and shape, as well as in the geographical coverage of inventory plots. The database has a relational structure, with 12 inter-connected tables that include information about plots, species names, dbh, and functional attributes of trees. A new system that corrects typographical errors and achieves taxonomic and nomenclatural standardization was developed using The Plant List (http://theplantlist.org/) as reference. Species distribution models have been computed for around 1700 species using different methods, and they will be publicly accessible through the web site in the future (http://portal.biotreenet.com). Although BIOTREE-NET has contributed to the development of improved species distribution models, its main potential lies, in our opinion, in studies at the community level. Finally, we emphasise the need to expand the network and encourage researchers willing to share data and to join the network and contribute to the generation of further knowledge about forest biodiversity in Neotropical regions

    TRY plant trait database – enhanced coverage and open access

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    Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Automated breast ultrasound for the detection of breast lesions: Comparison with hand-held ultrasound

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    Objetivos: Comparar la ecografía convencional frente a la ecografía automática de mama (ABUS) y la mamografía con tomosíntesis aislada en la detección y el diagnóstico de lesiones mamarias. Sujetos y métodos: Se incluyeron 155 mujeres sintomáticas y asintomáticas con mamas densas. Todas se realizaron mamografía y seguidamente ecografía manual y ABUS, que fueron interpretadas por 2 radiólogos diferentes. Los estudios fueron categorizados según el Breast Imaging Reporting and Data System (BI-RADS). Resultados: El índice kappa de concordancia fue de 0,83, p < 0,05. Los 5 carcinomas encontrados fueron diagnosticados por ambas técnicas de imagen de ultrasonidos, siendo en 2 de ellos la mamografía normal. ABUS detectó 2 lesiones benignas no vistas con la ecografía manual. Conclusión: ABUS demostró alta correlación con la ecografía manual detectando más lesiones benignas. El diagnóstico de las malignas fue equivalente con ambas técnicas, que fueron superiores a la mamografía de forma aislada. ABUS podría sustituir a la ecografía manual para complementar a la mamografía en la detección de cáncer de mama en mujeres con mama densa.Objectives: To compare automated breast ultrasound (ABUS) with hand-held ultrasound (HHUS) and tomosynthesis mammography in the detection and characterisation of breast lesions. Subjects and methods: A total of 155 symptomatic and asymptomatic women with dense breasts underwent tomosynthesis followed by ABUS and HHUS. The studies were read and graded by two different radiologists according to the Breast Imaging Reporting and Data System (BI-RADS). Results: The kappa index of agreement was 0.83, p < 0.05. All of the 5 carcinomas found were diagnosed by ABUS and HHUS. Tomosynthesis was normal in 2 out of 5 cases. ABUS identified 2 benign lesions not detected with HHUS. Conclusion: This study found a high correlation between ABUS and HHUS. More benign lesions were identified by ABUS while malignant lesions were detected equally by both techniques. ABUS and HHUS were superior to tomosynthesis in the detection of lesions. ABUS could replace HHUS, complementing mammography in the detection of lesions in women with dense breasts.Sin financiaciónNo data JCR 20180.120 SJR (2018) Q4, 319/381 Oncology, 287/341 Radiology, Nuclear Medicine and ImagingNo data IDR 2018UE
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