585 research outputs found

    eDNA in a bottleneck : obstacles to fish metabarcoding studies in megadiverse freshwater systems

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    The current capacity of environmental DNA (eDNA) to provide accurate insights into the biodiversity of megadiverse regions (e.g., the Neotropics) requires further evaluation to ensure its reliability for long‐term monitoring. In this study, we first evaluated the taxonomic resolution capabilities of a short fragment from the 12S rRNA gene widely used in fish eDNA metabarcoding studies, and then compared eDNA metabarcoding data from water samples with traditional sampling using nets. For the taxonomic discriminatory power analysis, we used a specifically curated reference dataset consisting of 373 sequences from 258 neotropical fish species (including 47 newly generated sequences) to perform a genetic distance‐based analysis of the amplicons targeted by the MiFish primer set. We obtained an optimum delimitation threshold value of 0.5% due to lowest cumulative errors. The barcoding gap analysis revealed only a 51.55% success rate in species recovery (133/258), highlighting a poor taxonomic resolution from the targeted amplicon. To evaluate the empirical performance of this amplicon for biomonitoring, we assessed fish biodiversity using eDNA metabarcoding from water samples collected from the Amazon (Adolpho Ducke Forest Reserve and two additional locations outside the Reserve). From a total of 84 identified Molecular Operational Taxonomic Units (MOTUs), only four could be assigned to species level using a fixed threshold. Measures of α‐diversity analyses within the Reserve showed similar patterns in each site between the number of MOTUs (eDNA dataset) and species (netting data) found. However, β‐diversity revealed contrasting patterns between the methods. We therefore suggest that a new approach is needed, underpinned by sound taxonomic knowledge, and a more thorough evaluation of better molecular identification procedures such as multi‐marker metabarcoding approaches and tailor‐made (i.e., order‐specific) taxonomic delimitation thresholds

    Sensori-motor adaptation to knee osteoarthritis during stepping-down before and after total knee replacement

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    BACKGROUND: Stepping-down is preceded by a shift of the center of mass towards the supporting side and forward. The ability to control both balance and lower limb movement was investigated in knee osteoarthritis patients before and after surgery. It was hypothesized that pain rather than knee joint mobility affects the coordination between balance and movement control. METHODS: The experiment was performed with 25 adult individuals. Eleven were osteoarthritic patients with damage restricted to one lower limb (8 right leg and 3 left leg). Subjects were recruited within two weeks before total knee replacement by the same orthopedic surgeon using the same prosthesis and technics of surgery. Osteoarthritic patients were tested before total knee replacement (pre-surgery session) and then, 9 of the 11 patients were tested one year after the surgery when re-educative training was completed (post-surgery session). 14 adult individuals (men: n = 7 and women: n = 7) were tested as the control group. RESULTS: The way in which the center of mass shift forward and toward the supporting side is initiated (timing and amplitude) did not vary within patients before and after surgery. In addition knee joint range of motion of the leading leg remained close to normal before and after surgery. However, the relative timing between both postural and movement phases was modified for the osteoarthritis supporting leg (unusual strategy for stepping-down) before surgery. The "coordinated" control of balance and movement turned to be a "sequential" mode of control; once the body weight transfer has been completed, the movement onset is triggered. This strategy could be aimed at shortening the duration-time supporting on the painful limb. However no such compensatory response was observed. CONCLUSION: The change in the strategy used when supporting on the arthritis and painful limb could result from the action of nociceptors that lead to increased proprioceptor thresholds, thus gating the proprioceptive inputs that may be the critical afferents in controlling the timing of the coordination between balance and movement initiation control

    Socioeconomic inequalities in childhood overweight: heterogeneity across five countries in the WHO European childhood obesity surveillance initiative (COSI-2008)

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    Free PMC Article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4856730/BACKGROUND: Excess risk of childhood overweight and obesity occurring in socioeconomically disadvantaged families has been demonstrated in numerous studies from high-income regions, including Europe. It is well known that socioeconomic characteristics such as parental education, income and occupation are etiologically relevant to childhood obesity. However, in the pan-European setting, there is reason to believe that inequalities in childhood weight status may vary among countries as a function of differing degrees of socioeconomic development and equity. SUBJECTS AND METHODS: In this cross-sectional study, we have examined socioeconomic differences in childhood obesity in different parts of the European region using nationally representative data from Bulgaria, the Czech Republic, Lithuania, Portugal and Sweden that were collected in 2008 during the first round of the World Health Organization (WHO) European Childhood Obesity Surveillance Initiative. RESULTS: Heterogeneity in the association between parental socioeconomic indicators and childhood overweight or obesity was clearly observed across the five countries studied. Positive as well as negative associations were observed between parental socioeconomic indicators and childhood overweight, with statistically significant interactions between country and parental indicators. CONCLUSIONS: These findings have public health implications for the WHO European Region and underscore the necessity to continue documenting socioeconomic inequalities in obesity in all countries through international surveillance efforts in countries with diverse geographic, social and economic environments. This is a prerequisite for universal as well as targeted preventive actions.info:eu-repo/semantics/publishedVersio

    Assessing the potential of environmental DNA metabarcoding for monitoring Neotropical mammals : a case study in the Amazon and Atlantic Forest, Brazil

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    The application of environmental DNA (eDNA) metabarcoding as a biomonitoring tool has greatly increased in the last decade. However, most studies have focused on aquatic macro-organisms in temperate areas (e.g., fishes). We apply eDNA metabarcoding to detect the mammalian community in two high-biodiversity regions of Brazil, the Amazon and Atlantic Forest. We identified critically endangered and endangered mammalian species in the Atlantic Forest and Amazon respectively and found overlap with species identified via camera trapping in the Atlantic Forest. In light of our results, we highlight the potential and challenges of eDNA monitoring for mammals in these highly biodiverse regions

    Scalable In Situ Hybridization on Tissue Arrays for Validation of Novel Cancer and Tissue-Specific Biomarkers

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    Tissue localization of gene expression is increasingly important for accurate interpretation of large scale datasets from expression and mutational analyses. To this end, we have (1) developed a robust and scalable procedure for generation of mRNA hybridization probes, providing >95% first-pass success rate in probe generation to any human target gene and (2) adopted an automated staining procedure for analyses of formalin-fixed paraffin-embedded tissues and tissue microarrays. The in situ mRNA and protein expression patterns for genes with known as well as unknown tissue expression patterns were analyzed in normal and malignant tissues to assess procedure specificity and whether in situ hybridization can be used for validating novel antibodies. We demonstrate concordance between in situ transcript and protein expression patterns of the well-known pathology biomarkers KRT17, CHGA, MKI67, PECAM1 and VIL1, and provide independent validation for novel antibodies to the biomarkers BRD1, EZH2, JUP and SATB2. The present study provides a foundation for comprehensive in situ gene set or transcriptome analyses of human normal and tumor tissues

    Oestrogen receptor Îą gene haplotype and postmenopausal breast cancer risk: a case control study

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    INTRODUCTION: Oestrogen receptor α, which mediates the effect of oestrogen in target tissues, is genetically polymorphic. Because breast cancer development is dependent on oestrogenic influence, we have investigated whether polymorphisms in the oestrogen receptor α gene (ESR1) are associated with breast cancer risk. METHODS: We genotyped breast cancer cases and age-matched population controls for one microsatellite marker and four single-nucleotide polymorphisms (SNPs) in ESR1. The numbers of genotyped cases and controls for each marker were as follows: TA(n), 1514 cases and 1514 controls; c.454-397C → T, 1557 cases and 1512 controls; c.454-351A → G, 1556 cases and 1512 controls; c.729C → T, 1562 cases and 1513 controls; c.975C → G, 1562 cases and 1513 controls. Using logistic regression models, we calculated odds ratios (ORs) and 95% confidence intervals (CIs). Haplotype effects were estimated in an exploratory analysis, using expectation-maximisation algorithms for case-control study data. RESULTS: There were no compelling associations between single polymorphic loci and breast cancer risk. In haplotype analyses, a common haplotype of the c.454-351A → G or c.454-397C → T and c.975C → G SNPs appeared to be associated with an increased risk for ductal breast cancer: one copy of the c.454-351A → G and c.975C → G haplotype entailed an OR of 1.19 (95% CI 1.06–1.33) and two copies with an OR of 1.42 (95% CI 1.15–1.77), compared with no copies, under a model of multiplicative penetrance. The association with the c.454-397C → T and c.975C → G haplotypes was similar. Our data indicated that these haplotypes were more influential in women with a high body mass index. Adjustment for multiple comparisons rendered the associations statistically non-significant. CONCLUSION: We found suggestions of an association between common haplotypes in ESR1 and the risk for ductal breast cancer that is stronger in heavy women

    Involvement of toll-like receptor 9 polymorphism in cervical cancer development

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    The role played by the polymorphism located in Toll-like Receptor 9 (TLR9) as a risk factor of cervical cancer remains elusive. Therefore, we studied the association of the TLR9 −1486 T/C (rs187084) and C2848T (rs352140) polymorphisms with cervical cancer. The TLR9 −1486 T/C and C2848T polymorphism was genotyped in 426 patients and 460 unrelated healthy females from the Polish population. Logistic regression analysis adjusting for age, pregnancy, oral contraceptive use, tobacco smoking, and menopausal status showed that both the TLR9 −1486 T/C and C2848T polymorphisms could be a genetic risk factor for cervical cancer. For the TLR9 −1486 T/C polymorphism, the adjusted OR for patients with the C/T genotype versus T/T genotype was 1.371 (95 % CI 1.021–1.842, p = 0.0361), the adjusted OR for the C/C genotype vs the T/T genotype was 1.300 (95 % CI 1.016–1.507, p = 0.0096), and the adjusted OR for the C/T or C/C genotype vs the T/T genotype was 1.448 (95 % CI 1.099–1.908, p = 0.0083). For the C2848T polymorphism, the adjusted OR for patients with the C/T genotype vs C/C genotype was 1.443 (95 % CI 1.019–2.043, p = 0.0380), the adjusted OR for the T/T genotype vs the C/C genotype was 1.237 (95 % CI 1.016–1.507, p = 0.0328), and the adjusted OR for the T/C or T/T genotype vs the C/C genotype was 1.345 (95 % CI 0.976–1.855, p = 0.0700). Our studies suggest that the TLR9 −1486 T/C and C2848T polymorphisms may be a genetic risk factor for cervical cancer
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