66 research outputs found

    Quantitative Analyse retinaler VerÀnderungen bei nichtglaukomatösen Optikusatrophien mit Hilfe der Optischen KohÀrenztomographie

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    Nichtglaukomatöse Optikusatrophien fĂŒhren nicht nur zu einer Verminderung der Dicke der retinalen Nervenfaserschicht (RNFL) sondern auch zu einer Reduktion des Makulavolumens. In dieser Arbeit wurde mit Hilfe der optischen KohĂ€renztomographie (OCT) untersucht, welche Schichten der Makula von DickenverĂ€nderungen als Folge einer Optikusatrophie betroffen sind. Es wurden 27 Patienten mit nichtglaukomatösen Optikusatrophien unterschiedlicher Ätiologie (postneuritische, hereditĂ€re und traumatische Atrophien) und 21 augengesunde Kontrollpersonen untersucht. OCT-Scans der RNFL und der Makula wurden mit Hilfe des Stratus OCT 3000 (Carl Zeiss Meditec) durchgefĂŒhrt. Die axialen ReflektivitĂ€tsprofile der radialen Scans wurden aus den exportierten JPEG-Bildern an zwölf Punkten in je 1,5mm Entfernung von der Foveola vermessen und gemittelt. Das charakteristische ReflektivitĂ€tsprofil mit fĂŒnf IntensitĂ€tsmaxima und vier IntensitĂ€tsminima wurde der Lokalisation der einzelnen Makulaschichten zugeordnet. Die von nichtglaukomatöser Optikusatrophie betroffenen Augen wiesen im Vergleich zu den Augen der augengesunden Normalpersonen signifikant (p<0,05) reduzierte RNFL-Dicken (um 35,5% reduziert) und Makulavolumen-Werte (um 11,8% reduziert) auf. Bei allen untersuchten Formen der Optikusatrophie waren nicht nur die makulĂ€re Nervenfaserschicht (MNFL) sondern alle inneren Schichten der Makula verdĂŒnnt. Die mittlere Reduktion betrug 21,2% fĂŒr die MNFL, 39,7% fĂŒr die Ganglienzellschicht, 33,2% fĂŒr die innere plexiforme Schicht und 9,4% fĂŒr die innere Körnerzellschicht im Vergleich zu den Werten der Normalpersonen. VerĂ€nderungen der Ă€ußeren Netzhautschichten traten nur bei den posttraumatischen Atrophien auf. Eine Beurteilung der Dicke aller einzelnen Netzhautschichten aus OCT-Scans ist mit Hilfe gerĂ€teintegrierter Software bisher noch nicht möglich. Die quantitative Analyse der axialen ReflektivitĂ€tsprofile aus exportierten OCT-Bildern stellt eine geeignete Methode zur Beschreibung des Verlaufs und der Lokalisation von MakulaverĂ€nderungen bei Optikusatrophien verschiedener Genese dar

    No Evidence for a Boost in Psychosocial Functioning in Older Age After a 6-Months Physical Exercise Intervention

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    The beneficial effects of physical exercise on physical health and cognitive functioning have been repeatedly shown. However, evidence of its effect on psychosocial functioning in healthy adults is still scarce or inconclusive. One limitation of many studies examining this link is their reliance on correlational approaches or specific subpopulations, such as clinical populations. The present study investigated the effects of a physical exercise intervention on key factors of psychosocial functioning, specifically well-being, stress, loneliness, and future time perspective. We used data from healthy, previously sedentary older adults (N = 132) who participated in a 6-month at-home intervention, either engaging in aerobic exercise or as part of a control group who participated in foreign language-learning or reading of selected native-language literature. Before and after the intervention, comprehensive cardiovascular pulmonary testing and a psychosocial questionnaire were administered. The exercise group showed significantly increased fitness compared to the control group. Contrary to expectations, however, we did not find evidence for a beneficial effect of this fitness improvement on any of the four domains of psychosocial functioning we assessed. This may be due to pronounced stability of such psychological traits in older age, especially in older adults who show high levels of well-being initially. Alternatively, it may be that the well-documented beneficial effects of physical exercise on brain structure and function, as well as cognition differ markedly from beneficial effects on psychosocial functioning. While aerobic exercise may be the driving factor for the former, positive effects on the latter may only be invoked by other aspects of exercise, for example, experiences of mastery or a feeling of community.Peer Reviewe

    A regionally informed abundance index for supporting integrative analyses across butterfly monitoring schemes

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    1. The rapid expansion of systematic monitoring schemes necessitates robust methods to reliably assess species' status and trends. Insect monitoring poses a challenge where there are strong seasonal patterns, requiring repeated counts to reliably assess abundance. Butterfly monitoring schemes (BMSs) operate in an increasing number of countries with broadly the same methodology, yet they differ in their observation frequency and in the methods used to compute annual abundance indices. 2. Using simulated and observed data, we performed an extensive comparison of two approaches used to derive abundance indices from count data collected via BMS, under a range of sampling frequencies. Linear interpolation is most commonly used to estimate abundance indices from seasonal count series. A second method, hereafter the regional generalized additive model (GAM), fits a GAM to repeated counts within sites across a climatic region. For the two methods, we estimated bias in abundance indices and the statistical power for detecting trends, given different proportions of missing counts. We also compared the accuracy of trend estimates using systematically degraded observed counts of the Gatekeeper Pyronia tithonus (Linnaeus 1767). 3. The regional GAM method generally outperforms the linear interpolation method. When the proportion of missing counts increased beyond 50%, indices derived via the linear interpolation method showed substantially higher estimation error as well as clear biases, in comparison to the regional GAM method. The regional GAM method also showed higher power to detect trends when the proportion of missing counts was substantial. 4. Synthesis and applications. Monitoring offers invaluable data to support conservation policy and management, but requires robust analysis approaches and guidance for new and expanding schemes. Based on our findings, we recommend the regional generalized additive model approach when conducting integrative analyses across schemes, or when analysing scheme data with reduced sampling efforts. This method enables existing schemes to be expanded or new schemes to be developed with reduced within-year sampling frequency, as well as affording options to adapt protocols to more efficiently assess species status and trends across large geographical scales

    Cumulative Burden of Colorectal Cancer-Associated Genetic Variants Is More Strongly Associated With Early-Onset vs Late-Onset Cancer.

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    BACKGROUND & AIMS: Early-onset colorectal cancer (CRC, in persons younger than 50 years old) is increasing in incidence; yet, in the absence of a family history of CRC, this population lacks harmonized recommendations for prevention. We aimed to determine whether a polygenic risk score (PRS) developed from 95 CRC-associated common genetic risk variants was associated with risk for early-onset CRC. METHODS: We studied risk for CRC associated with a weighted PRS in 12,197 participants younger than 50 years old vs 95,865 participants 50 years or older. PRS was calculated based on single nucleotide polymorphisms associated with CRC in a large-scale genome-wide association study as of January 2019. Participants were pooled from 3 large consortia that provided clinical and genotyping data: the Colon Cancer Family Registry, the Colorectal Transdisciplinary Study, and the Genetics and Epidemiology of Colorectal Cancer Consortium and were all of genetically defined European descent. Findings were replicated in an independent cohort of 72,573 participants. RESULTS: Overall associations with CRC per standard deviation of PRS were significant for early-onset cancer, and were stronger compared with late-onset cancer (P for interaction = .01); when we compared the highest PRS quartile with the lowest, risk increased 3.7-fold for early-onset CRC (95% CI 3.28-4.24) vs 2.9-fold for late-onset CRC (95% CI 2.80-3.04). This association was strongest for participants without a first-degree family history of CRC (P for interaction = 5.61 × 10-5). When we compared the highest with the lowest quartiles in this group, risk increased 4.3-fold for early-onset CRC (95% CI 3.61-5.01) vs 2.9-fold for late-onset CRC (95% CI 2.70-3.00). Sensitivity analyses were consistent with these findings. CONCLUSIONS: In an analysis of associations with CRC per standard deviation of PRS, we found the cumulative burden of CRC-associated common genetic variants to associate with early-onset cancer, and to be more strongly associated with early-onset than late-onset cancer, particularly in the absence of CRC family history. Analyses of PRS, along with environmental and lifestyle risk factors, might identify younger individuals who would benefit from preventive measures

    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

    Quantitative Analyse retinaler VerÀnderungen bei nichtglaukomatösen Optikusatrophien mit Hilfe der Optischen KohÀrenztomographie

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    Nichtglaukomatöse Optikusatrophien fĂŒhren nicht nur zu einer Verminderung der Dicke der retinalen Nervenfaserschicht (RNFL) sondern auch zu einer Reduktion des Makulavolumens. In dieser Arbeit wurde mit Hilfe der optischen KohĂ€renztomographie (OCT) untersucht, welche Schichten der Makula von DickenverĂ€nderungen als Folge einer Optikusatrophie betroffen sind. Es wurden 27 Patienten mit nichtglaukomatösen Optikusatrophien unterschiedlicher Ätiologie (postneuritische, hereditĂ€re und traumatische Atrophien) und 21 augengesunde Kontrollpersonen untersucht. OCT-Scans der RNFL und der Makula wurden mit Hilfe des Stratus OCT 3000 (Carl Zeiss Meditec) durchgefĂŒhrt. Die axialen ReflektivitĂ€tsprofile der radialen Scans wurden aus den exportierten JPEG-Bildern an zwölf Punkten in je 1,5mm Entfernung von der Foveola vermessen und gemittelt. Das charakteristische ReflektivitĂ€tsprofil mit fĂŒnf IntensitĂ€tsmaxima und vier IntensitĂ€tsminima wurde der Lokalisation der einzelnen Makulaschichten zugeordnet. Die von nichtglaukomatöser Optikusatrophie betroffenen Augen wiesen im Vergleich zu den Augen der augengesunden Normalpersonen signifikant (p<0,05) reduzierte RNFL-Dicken (um 35,5% reduziert) und Makulavolumen-Werte (um 11,8% reduziert) auf. Bei allen untersuchten Formen der Optikusatrophie waren nicht nur die makulĂ€re Nervenfaserschicht (MNFL) sondern alle inneren Schichten der Makula verdĂŒnnt. Die mittlere Reduktion betrug 21,2% fĂŒr die MNFL, 39,7% fĂŒr die Ganglienzellschicht, 33,2% fĂŒr die innere plexiforme Schicht und 9,4% fĂŒr die innere Körnerzellschicht im Vergleich zu den Werten der Normalpersonen. VerĂ€nderungen der Ă€ußeren Netzhautschichten traten nur bei den posttraumatischen Atrophien auf. Eine Beurteilung der Dicke aller einzelnen Netzhautschichten aus OCT-Scans ist mit Hilfe gerĂ€teintegrierter Software bisher noch nicht möglich. Die quantitative Analyse der axialen ReflektivitĂ€tsprofile aus exportierten OCT-Bildern stellt eine geeignete Methode zur Beschreibung des Verlaufs und der Lokalisation von MakulaverĂ€nderungen bei Optikusatrophien verschiedener Genese dar
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