226 research outputs found

    Complexity of biogeographic pattern in the endangered crayfish Austropotamobius italicus in northern Italy: molecular insights of conservation concern.

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    The protection of freshwater biodiversity has become a priority task for conservation practices, as freshwater ecosystems host high levels of cryptic diversity, while also record similarly high rates of extinction. The Italian white-clawed crayfish Austropotamobius italicus is an endemic freshwater crustacean, threatened by several anthropogenic impacts such as habitat fragmentation, pol- lution, invasion of exotics, and climate change. Previous phylogenetic studies conducted in Italy pointed out a complex phylogeographic framework for the species, with four different subspecies currently recognized. Conserva- tion efforts, particularly when involving restocking and reintroduction, require a detailed knowledge of their pop- ulation genetics. In this study we describe the genetic structure of A. italicus populations in northern Italy (Lombardy Alpine foothills and northern Apennines) by using the informative mitochondrial marker cytochrome c oxidase subunit I, in order to assess their current evolu- tionary diversity and past phylogeographic history from a conservation perspective. Our results contribute to the mapping of the contact area among A. i. carsicus and A. i. carinthiacus in the Orobie Larian Prealps. Moreinterestingly, we highlight the existence of two deeply differentiated evolutionary lineages within A. i. carsicus, showing alternative phylogeographic patterns and past demographic trends. We propose to consider these two clades as distinct molecular operational taxonomic units for the conservation of this endangered crayfish

    Orientation and symmetries of Alexandrov spaces with applications in positive curvature

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    We develop two new tools for use in Alexandrov geometry: a theory of ramified orientable double covers and a particularly useful version of the Slice Theorem for actions of compact Lie groups. These tools are applied to the classification of compact, positively curved Alexandrov spaces with maximal symmetry rank.Comment: 34 pages. Simplified proofs throughout and a new proof of the Slice Theorem, correcting omissions in the previous versio

    Prognostic and predictive role of neutrophil/lymphocytes ratio in metastatic colorectal cancer: a retrospective analysis of the TRIBE study by GONO.

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    Background Neutrophil/lymphocyte ratio (NLR), defined as absolute neutrophils count divided by absolute lymphocytes count, has been reported as poor prognostic factor in several neoplastic diseases but only a few data are available about unresectable metastatic colorectal cancer (mCRC) patients (pts). The aim of our study was to evaluate the prognostic and predictive role of NLR in the TRIBE trial. Patients and methods Pts enrolled in TRIBE trial were included. TRIBE is a multicentre phase III trial randomizing unresectable and previously untreated mCRC pts to receive FOLFOXIRI or FOLFIRI plus bevacizumab. A cut-off value of 3 was adopted to discriminate pts with low (NLR < 3) versus high (NLR ≄ 3) NLR, as primary analysis. As secondary analysis, NLR was treated as an ordinal variable with three levels based on terciles distribution. Results NLR at baseline was available for 413 patients. After multiple imputation at univariate analysis, patients with high NLR had significantly shorter progression-free survival (PFS) [hazard ratio (HR) 1.27 (95% CI 1.05-1.55), P = 0.017] and overall survival (OS) [HR 1.56 (95% CI 1.25-1.95), P < 0.001] than patients with low NLR. In the multivariable model, NLR retained a significant association with OS [HR 1.44 (95% CI 1.14-1.82), P = 0.014] but not with PFS [HR 1.18 (95% CI 0.95-1.46), P = 0.375]. No interaction effect between treatment arm and NLR was evident in terms of PFS (P for interaction = 0.536) or OS (P for interaction = 0.831). Patients with low [HR 0.84 (95% CI 0.64-1.08)] and high [HR 0.73 (95% CI 0.54-0.97)] NLR achieved similar PFS benefit from the triplet and consistent results were obtained in terms of OS [HR 0.83 (95% CI 0.62-1.12) for low NLR; HR 0.82 (95% CI 0.59-1.12) for high NLR]. Conclusion This study confirmed the prognostic role of NLR in mCRC pts treated with bevacizumab plus chemotherapy in the first line, showing the worse prognosis of pts with high NLR. The advantage of the triplet is independent of NLR at baseline

    Environmental Predictors of Seasonal Influenza Epidemics across Temperate and Tropical Climates

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    Human influenza infections exhibit a strong seasonal cycle in temperate regions. Recent laboratory and epidemiological evidence suggests that low specific humidity conditions facilitate the airborne survival and transmission of the influenza virus in temperate regions, resulting in annual winter epidemics. However, this relationship is unlikely to account for the epidemiology of influenza in tropical and subtropical regions where epidemics often occur during the rainy season or transmit year-round without a well-defined season. We assessed the role of specific humidity and other local climatic variables on influenza virus seasonality by modeling epidemiological and climatic information from 78 study sites sampled globally. We substantiated that there are two types of environmental conditions associated with seasonal influenza epidemics: “cold-dry” and “humid-rainy”. For sites where monthly average specific humidity or temperature decreases below thresholds of approximately 11–12 g/kg and 18–21°C during the year, influenza activity peaks during the cold-dry season (i.e., winter) when specific humidity and temperature are at minimal levels. For sites where specific humidity and temperature do not decrease below these thresholds, seasonal influenza activity is more likely to peak in months when average precipitation totals are maximal and greater than 150 mm per month. These findings provide a simple climate-based model rooted in empirical data that accounts for the diversity of seasonal influenza patterns observed across temperate, subtropical and tropical climates

    Integrated Molecular-Morphologic Meningioma Classification: A Multicenter Retrospective Analysis, Retrospectively and Prospectively Validated

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    PURPOSE: Meningiomas are the most frequent primary intracranial tumors. Patient outcome varies widely from benign to highly aggressive, ultimately fatal courses. Reliable identification of risk of progression for individual patients is of pivotal importance. However, only biomarkers for highly aggressive tumors are established (CDKN2A/B and TERT), whereas no molecularly based stratification exists for the broad spectrum of patients with low- and intermediate-risk meningioma. METHODS: DNA methylation data and copy-number information were generated for 3,031 meningiomas (2,868 patients), and mutation data for 858 samples. DNA methylation subgroups, copy-number variations (CNVs), mutations, and WHO grading were analyzed. Prediction power for outcome was assessed in a retrospective cohort of 514 patients, validated on a retrospective cohort of 184, and on a prospective cohort of 287 multicenter cases. RESULTS: Both CNV- and methylation family-based subgrouping independently resulted in increased prediction accuracy of risk of recurrence compared with the WHO classification (c-indexes WHO 2016, CNV, and methylation family 0.699, 0.706, and 0.721, respectively). Merging all risk stratification approaches into an integrated molecular-morphologic score resulted in further substantial increase in accuracy (c-index 0.744). This integrated score consistently provided superior accuracy in all three cohorts, significantly outperforming WHO grading (c-index difference P = .005). Besides the overall stratification advantage, the integrated score separates more precisely for risk of progression at the diagnostically challenging interface of WHO grade 1 and grade 2 tumors (hazard ratio 4.34 [2.48-7.57] and 3.34 [1.28-8.72] retrospective and prospective validation cohorts, respectively). CONCLUSION: Merging these layers of histologic and molecular data into an integrated, three-tiered score significantly improves the precision in meningioma stratification. Implementation into diagnostic routine informs clinical decision making for patients with meningioma on the basis of robust outcome prediction

    Public, private and personal: Qualitative research on policymakers' opinions on smokefree interventions to protect children in 'private' spaces

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    <p>Abstract</p> <p>Background</p> <p>Governments use law to constrain aspects of private activities for purposes of protecting health and social wellbeing. Policymakers have a range of perceptions and beliefs about what is public or private. An understanding of the possible drivers of policymaker decisions about where government can or should intervene for health is important, as one way to better guide appropriate policy formation. Our aim was to identify obstacles to, and opportunities for, government smokefree regulation of private and public spaces to protect children. In particular, to seek policymaker opinions on the regulation of smoking in homes, cars and public parks and playgrounds in a country with incomplete smokefree laws (New Zealand).</p> <p>Methods</p> <p>Case study, using structured interviews to ask policymakers (62 politicians and senior officials) about their opinions on new smokefree legislation for public and private places. Supplementary data was obtained from the Factiva media database, on the views of New Zealand local authority councillors about policies for smokefree outdoor public places.</p> <p>Results</p> <p>Overall, interviewees thought that government regulation of smoking in private places was impractical and unwise. However, there were some differences on what <it>was </it>defined as 'private', particularly for cars. Even in public parks, smoking was seen by some as a 'personal' decision, and unlikely to be amenable to regulation. Most participants believed that educative, supportive and community-based measures were better and more practical means of reducing smoking in private places, compared to regulation.</p> <p>Conclusions</p> <p>The constrained view of the role of regulation of smoking in public and private domains may be in keeping with current political discourse in New Zealand and similar Anglo-American countries. Policy and advocacy options to promote additional smokefree measures include providing a better voice for childrens' views, increasing information to policymakers about the harms to children from secondhand smoke and the example of adult smoking, and changing the culture for smoking around children.</p

    Double sampling of a faecal immunochemical test is not superior to single sampling for detection of colorectal neoplasia: a colonoscopy controlled prospective cohort study

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    <p>Abstract</p> <p>Background</p> <p>A single sampled faecal immunochemical test (FIT) has moderate sensitivity for colorectal cancer and advanced adenomas. Repeated FIT sampling could improve test sensitivity. The aim of the present study is to determine whether any of three different strategies of double FIT sampling has a better combination of sensitivity and specificity than single FIT sampling.</p> <p>Methods</p> <p>Test performance of single FIT sampling in subjects scheduled for colonoscopy was compared to double FIT sampling intra-individually. Test positivity of double FIT sampling was evaluated in three different ways: 1) "one of two FITs+" when at least one out of two measurements exceeded the cut-off value, 2) "two of two FITs+" when both measurements exceeded the cut-off value, 3) "mean of two FITs+" when the geometric mean of two FITs exceeded the cut-off value. Receiver operator curves were calculated and sensitivity of single and the three strategies of double FIT sampling were compared at a fixed level of specificity.</p> <p>Results</p> <p>In 124 of 1096 subjects, screen relevant neoplasia (SRN) were found (i.e. early stage CRC or advanced adenomas). At any cut-off, "two of two FITs+" resulted in the lowest and "one of two FITs+" in the highest sensitivity for SRN (range 35-44% and 42%-54% respectively). ROC's of double FIT sampling were similar to single FIT sampling. At specificities of 85/90/95%, sensitivity of any double FIT sampling strategy did not differ significantly from single FIT (p-values 0.07-1).</p> <p>Conclusion</p> <p>At any cut off, "one of two FITs+" is the most sensitive double FIT sampling strategy. However, at a given specificity level, sensitivity of any double FIT sampling strategy for SRN is comparable to single FIT sampling at a different cut-off value. None of the double FIT strategies has a superior combination of sensitivity and specificity over single FIT.</p
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