1,052 research outputs found

    Analysis of the circadian transcriptome of the Antarctic krill Euphausia superba

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    Antarctic krill (Euphausia superba) is a high latitude pelagic organism which plays a central role in the Southern Ocean ecosystem. E. superba shows daily and seasonal rhythms in physiology and behaviour, which are synchronized with the environmental cycles of its habitat. Recently, the main components of the krill circadian machinery have been identified and characterized. However, the exact mechanisms through which the endogenous timing system operates the control and regulation of the overt rhythms remains only partially understood. Here we investigate the involvement of the circadian clock in the temporal orchestration of gene expression by using a newly developed version of a krill microarray platform. The analysis of transcriptome data from krill exposed to both light-dark cycles (LD 18:6) and constant darkness (DD), has led to the identification of 1,564 putative clock-controlled genes. A remarkably large proportion of such genes, including several clock components (clock, period, cry2, vrille, and slimb), show oscillatory expression patterns in DD, with a periodicity shorter than 24\u2009hours. Energy-storage pathways appear to be regulated by the endogenous clock in accordance with their ecological relevance in daily energy managing and overwintering. Our results provide the first representation of the krill circadian transcriptome under laboratory, free-running conditions

    How relationship norms shape moral obligation in cancelation behavior

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    Shuqair, S., Costa Pinto, D., Cruz-Jesus, F., Mattila, A. S., da Fonseca Guerreiro, P., & Kam Fung So, K. (2022). Can customer relationships backfire? : How relationship norms shape moral obligation in cancelation behavior. Journal of Business Research, 151(November), 463-472. https://doi.org/10.1016/j.jbusres.2022.07.008 ---Funding Information: The authors Diego and Frederico gratefully acknowledge financial support from FCT Fundação para a Ciência e a Tecnologia (Portugal), national funding through research grant Information Management Research Center – MagIC/NOVA IMS (UIDB/04152/2020).While prior research indicates that establishing interpersonal interaction with customers is mostly beneficial, this work reveals that the impact of social ties depends on relationship norms (communal vs. exchange). In three studies, including a real-world field dataset (N = 87,615 customers), the current investigation demonstrates the conditions under which interpersonal relationships can increase or decrease customers’ cancelation behavior. The findings indicate that communal (vs. exchange) relationships can increase customers’ future cancelation behaviors. The findings also demonstrate that perceived moral obligation underlies interpersonal effects on cancelation behavior. That is, when providers develop communal (vs. exchange) ties, consumers feel that their interaction with the providers is in a closed social context, which tends to reduce their obligations towards attending their booking, thus increasing cancelation behavior. Theoretical and practical implications for business researchers and practitioners are discussed.publishersversionpublishe

    Problematic placebos in physical therapy trials

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    The placebo controlled, randomised controlled trial is widely recognised as the gold standard design for providing evidence in health care. Yet controversies surrounding placebos persist, which include issues regarding ethics, legality, mechanisms, and even whether there should be such a thing as placebo at all. Here, we intend to highlight some of the difficulties in the design and use of placebo controls within physical therapy trials. Unlike placebo tablets, which can be constructed simply by removing the active or‘characteristic’ingredient, physical therapy treatments are often more complex, with many active features that cannot be easily separated. Based on the challenges of isolating the characteristic feature(s) of treatments, we explore the problem with constructing placebos in trials of physical therapies, drawing on philosophy of science as a basis for defining what a placebo is and is not. After pointing out common problems, we outline potential solutions using alternative designs that allow trials to remain rigorous, while at the same time avoiding the pitfalls introduced when using inadequate placebos

    Comparison of two DNA targets for the diagnosis of Toxoplasmosis by real-time PCR using fluorescence resonance energy transfer hybridization probes

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    BACKGROUND: Toxoplasmosis is an infectious disease caused by the parasitic protozoan Toxoplasma gondii. It is endemic worldwide and, depending on the geographic location, 15 to 85% of the human population are asymptomatically infected. Routine diagnosis is based on serology. The parasite has emerged as a major opportunistic pathogen for immunocompromised patients, in whom it can cause life-threatening disease. Moreover, when a pregnant woman develops a primary Toxoplasma gondii infection, the parasite may be transmitted to the fetus and cause serious damnage. For these two subpopulations, a rapid and accurate diagnosis is required to initiate treatment. Serological diagnosis of active infection is unreliable because reactivation is not always accompanied by changes in antibody levels, and the presence of IgM does not necessarily indicate recent infection. Application of quantitative PCR has evolved as a sensitive, specific, and rapid method for the detection of Toxoplasma gondii DNA in amniotic fluid, blood, tissue samples, and cerebrospinal fluid. METHODS: Two separate, real-time fluorescence PCR assays were designed and evaluated with clinical samples. The first, targeting the 35-fold repeated B1 gene, and a second, targeting a newly described multicopy genomic fragment of Toxoplasma gondii. Amplicons of different intragenic copies were analyzed for sequence heterogeneity. RESULTS: Comparative LightCycler experiments were conducted with a dilution series of Toxoplasma gondii genomic DNA, 5 reference strains, and 51 Toxoplasma gondii-positive amniotic fluid samples revealing a 10 to 100-fold higher sensitivity for the PCR assay targeting the newly described 529-bp repeat element of Toxoplasma gondii. CONCLUSION: We have developed a quantitative LightCycler PCR protocol which offer rapid cycling with real-time, sequence-specific detection of amplicons. Results of quantitative PCR demonstrate that the 529-bp repeat element is repeated more than 300-fold in the genome of Toxoplasma gondii. Since individual intragenic copies of the target are conserved on sequence level, the high copy number leads to an ultimate level of analytical sensitivity in routine practice. This newly described 529-bp repeat element should be preferred to less repeated or more divergent target sequences in order to improve the sensitivity of PCR tests for the diagnosis of toxoplasmosis

    HERVs establish a distinct molecular subtype in stage II/III colorectal cancer with poor outcome

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    © The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Colorectal cancer (CRC) is one of the most lethal malignancies. The extreme heterogeneity in survival rate is driving the need for new prognostic biomarkers. Human endogenous retroviruses (hERVs) have been suggested to influence tumor progression, oncogenesis and elicit an immune response. We examined multiple next-generation sequencing (NGS)-derived biomarkers in 114 CRC patients with paired whole-exome and whole-transcriptome sequencing (WES and WTS, respectively). First, we demonstrate that the median expression of hERVs can serve as a potential biomarker for prognosis, relapse, and resistance to chemotherapy in stage II and III CRC. We show that hERV expression and CD8+ tumor-infiltrating T-lymphocytes (TILs) synergistically stratify overall and relapse-free survival (OS and RFS): the median OS of the CD8-/hERV+ subgroup was 29.8 months compared with 37.5 months for other subgroups (HR = 4.4, log-rank P < 0.001). Combing NGS-based biomarkers (hERV/CD8 status) with clinicopathological factors provided a better prediction of patient survival compared to clinicopathological factors alone. Moreover, we explored the association between genomic and transcriptomic features of tumors with high hERV expression and establish this subtype as distinct from previously described consensus molecular subtypes of CRC. Overall, our results underscore a previously unknown role for hERVs in leading to a more aggressive subtype of CRC.The biobanking of CRC from Hospital Santa Maria, Lisbon, Portugal, was supported by a grant from the Official Portuguese Funding Agency for Science and Technology (FCT: PIC/IC/82821/2007).info:eu-repo/semantics/publishedVersio

    Genetic and microenvironmental intra-tumor heterogeneity impacts colorectal cancer evolution and metastatic development

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    © The Author(s) 2022 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Colorectal cancer (CRC) is a highly diverse disease, where different genomic instability pathways shape genetic clonal diversity and tumor microenvironment. Although intra-tumor heterogeneity has been characterized in primary tumors, its origin and consequences in CRC outcome is not fully understood. Therefore, we assessed intra- and inter-tumor heterogeneity of a prospective cohort of 136 CRC samples. We demonstrate that CRC diversity is forged by asynchronous forms of molecular alterations, where mutational and chromosomal instability collectively boost CRC genetic and microenvironment intra-tumor heterogeneity. We were able to depict predictor signatures of cancer-related genes that can foresee heterogeneity levels across the different tumor consensus molecular subtypes (CMS) and primary tumor location. Finally, we show that high genetic and microenvironment heterogeneity are associated with lower metastatic potential, whereas late-emerging copy number variations favor metastasis development and polyclonal seeding. This study provides an exhaustive portrait of the interplay between genetic and microenvironment intra-tumor heterogeneity across CMS subtypes, depicting molecular events with predictive value of CRC progression and metastasis development.This work was financed by national funds from FCT - Fundação para a Ciência e a Tecnologia, I.P., in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences - UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy - i4HB. This research was also funded by: PTDC/MED-ONC/28660/2017 from Fundação para a Ciência e Tecnologia (FCT) to A.R.G. A.R.G is recipient of Researcher Grant CEECIND/02699/2017 from FCT. The biobanking of CRC samples from Hospital Santa Maria, Lisbon, Portugal was supported by FCT research grant PIC/IC/82821/2007. This work was produced with the support of INCD funded by FCT and FEDER under the project 22153-01/SAICT/2016.info:eu-repo/semantics/publishedVersio

    Metabolic Syndrome Predicts New Onset of Chronic Kidney Disease in 5,829 Patients With Type 2 Diabetes: A 5-year prospective analysis of the Hong Kong Diabetes Registry

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    OBJECTIVE—Type 2 diabetes is the leading cause of end-stage renal disease worldwide. Aside from hyperglycemia and hypertension, other metabolic factors may determine renal outcome. We examined risk associations of metabolic syndrome with new onset of chronic kidney disease (CKD) in 5,829 Chinese patients with type 2 diabetes enrolled between 1995 and 2005

    Evaluation of rK39 rapid diagnostic tests for canine visceral leishmaniasis : longitudinal study and meta-analysis

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    Canine visceral leishmaniasis is a vector-borne disease caused by the intracellular parasite Leishmania infantum. It is an important veterinary disease, and dogs are also the main animal reservoir for human infection. The disease is widespread in the Mediterranean area, and parts of Asia and South and Central America, and is potentially fatal in both dogs and humans unless treated. Diagnosis of canine infections requires serological or molecular tests. Detection of infection in dogs is important prior to treatment, and in epidemiological studies and control programmes, and a sensitive and specific rapid diagnostic test would be very useful. Rapid diagnostic tests (RDTs) have been developed, but their diagnostic performance has been reported to be variable. We evaluated the sensitivity of a RDT based on serological detection of the rK39 antigen in a cohort of naturally infected Brazilian dogs. The sensitivity of the test to detect infection was relatively low, but increased with time since infection and the severity of infection. We then carried out a meta-analysis of published studies of rK39 RDTs, evaluating the sensitivity to detect disease and infection. The results suggest that rK39 RDTs may be useful in a veterinary clinical setting, but the sensitivity to detect infection is too low for operational control programmes
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