21 research outputs found

    Individual Black-tailed Godwits do not stick to single routes:A hypothesis on how low population densities might decrease social conformity

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    The miniaturization of tracking devices is now rapidly increasing our knowledge on the spatiotemporal organization of seasonal migration. So far, most studies aimed at understanding within- and between-individual variation in migratory routines focus on single populations. This has also been the case for continental Black-tailed Godwits Limosa l. limosa (hereafter Godwits), with most work carried out on individuals from the Dutch breeding population, migrating in relatively large numbers in the westernmost part of the range. Here we report the migratory timing and routes of four adult individuals of the same subspecies from the low-density population in eastern Poland and compare this with previously published data on Godwits breeding in The Netherlands. During northward migration, the birds from Poland departed and arrived later from their wintering and breeding grounds. However, on southward migration the Polish breeding Godwits departed earlier, but arrived one month later than the Dutch birds on their wintering grounds in sub-Saharan Africa. Despite the small sample size of tracked birds from Poland, we find a significantly higher between-individual variation in timing during southward migration in Polish Godwits as compared to the Dutch Godwits. Furthermore, not only did migratory routes differ, but the few Polish Godwits tracked showed a higher level of between- and within-individual variation in route choice during both southward and northward migration. To explain this remarkable discrepancy, we propose that the properties of transmission of social information may be different between Godwits from a high-density population (i.e. the one in The Netherlands) and a low-density population (in Poland) and that this leads to different levels of canalization. To examine this hypothesis, future studies should not only follow individuals from an early age onwards, but also quantify and experimentally manipulate their social environments during migration

    Lipid droplet degradation by autophagy connects mitochondria metabolism to Prox1-driven expression of lymphatic genes and lymphangiogenesis.

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    Autophagy has vasculoprotective roles, but whether and how it regulates lymphatic endothelial cells (LEC) homeostasis and lymphangiogenesis is unknown. Here, we show that genetic deficiency of autophagy in LEC impairs responses to VEGF-C and injury-driven corneal lymphangiogenesis. Autophagy loss in LEC compromises the expression of main effectors of LEC identity, like VEGFR3, affects mitochondrial dynamics and causes an accumulation of lipid droplets (LDs) in vitro and in vivo. When lipophagy is impaired, mitochondrial ATP production, fatty acid oxidation, acetyl-CoA/CoA ratio and expression of lymphangiogenic PROX1 target genes are dwindled. Enforcing mitochondria fusion by silencing dynamin-related-protein 1 (DRP1) in autophagy-deficient LEC fails to restore LDs turnover and lymphatic gene expression, whereas supplementing the fatty acid precursor acetate rescues VEGFR3 levels and signaling, and lymphangiogenesis in LEC-Atg5-/- mice. Our findings reveal that lipophagy in LEC by supporting FAO, preserves a mitochondrial-PROX1 gene expression circuit that safeguards LEC responsiveness to lymphangiogenic mediators and lymphangiogenesis.We thank K. Rillaerts, J. Souffreau, and A. Bouche, for expert technical support and Dr. A. Luttun and Dr. A. Zijsen for sharing tools and advices. P.A. is supported by grants from the Flemish Research Foundation (FWO-Vlaanderen; G076617N, G049817N, G070115N), the EOS MetaNiche consortium N degrees 40007532, Stichting tegen Kanker (FAF-F/2018/1252) and the iBOF/21/053 ATLANTIS consortium with G.B. D.H. is the recipient of an FWO Doctoral Fellowship from the Flemish Research Foundation (FWO-Vlaanderen, 1186019N), Belgium. M.B. is supported by the `Fonds voor Wetenschappelijk Onderzoek' (FWO). K.J. is the recipient of an FWO Postdoctoral Fellowship from the Flemish Research Foundation (FWO-Vlaanderen). P.C. is supported by Methusalem funding by the Flemish government, and by an ERC Advanced Research Grant (EU-ERC269073).S

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Risk factors and prognostic models for preterm birth

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    Tussen 2000 en 2007 vond een significante afname plaats van zowel het risico op vroeggeboorte als het risico op perinatale sterfte. Dit toont Jelle Schaaf aan in zijn onderzoek. Er blijkt wel verschil te zijn tussen etnische groepen. Zo blijken donkere vrouwen van Afrikaanse afkomst een hoger risico op vroeggeboorte te hebben dan blanke vrouwen, maar weer een lager risico op neonatale complicaties. Mediterrane vrouwen hebben zowel een verlaagd risico op vroeggeboorte als een verlaagd risico op neonatale complicaties. Vergeleken met Europese blanke vrouwen hebben de overige etnische groepen een verlaagd risico op neonatale complicaties na vroeggeboorte. Bij een identieke zwangerschapsduur lijken pasgeborenen van Afrikaanse, Zuid-Aziatische, mediterrane en Oost-Aziatische moeders beter bestand te zijn tegen de schadelijke impact van vroeggeboorte. Een eerdere vroeggeboorte vormt een van de belangrijkste risicofactoren voor een volgende vroeggeboorte

    How do children with speech sound disorders perform on language and motor skills of children compared to typically developing children?

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    Children with speech sound disorders (SSD) have speech disorders due to problems in articulation, phonology, execution (eg. dysarthria), planning (eg. apraxia), orofacial anomalies (eg. cleft palate) or hearing impairment (ASHA). How do children with speech sound disorders perform on language and motor (experimental) tests compared to typically developing children

    Development of a prognostic model for predicting spontaneous singleton preterm birth

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    Objective: To develop and validate a prognostic model for prediction of spontaneous preterm birth. Study design: Prospective cohort study using data of the nationwide perinatal registry in The Netherlands. We studied 1,524,058 singleton pregnancies between 1999 and 2007. We developed a multiple logistic regression model to estimate the risk of spontaneous preterm birth based on maternal and pregnancy characteristics. We used bootstrapping techniques to internally validate our model. Discrimination (AUC), accuracy (Brier score) and calibration (calibration graphs and Hosmer-Lemeshow C-statistic) were used to assess the model's predictive performance. Our primary outcome measure was spontaneous preterm birth at <37 completed weeks. Results: Spontaneous preterm birth occurred in 57,796 (3.8%) pregnancies. The final model included 13 variables for predicting preterm birth. The predicted probabilities ranged from 0.01 to 0.71 (IQR 0.02-0.04). The model had an area under the receiver operator characteristic curve (AUC) of 0.63(95% Cl 0.63-0.63), the Brier score was 0.04 (95% Cl 0.04-0.04) and the Hosmer Lemeshow C-statistic was significant (p <0.0001). The calibration graph showed overprediction at higher values of predicted probability. The positive predictive value was 26% (95% Cl 20-33%) for the 0.4 probability cut-off point. Conclusions: The model's discrimination was fair and it had modest calibration. Previous preterm birth, drug abuse and vaginal bleeding in the first half of pregnancy were the most important predictors for spontaneous preterm birth. Although not applicable in clinical practice yet, this model is a next step towards early prediction of spontaneous preterm birth that enables caregivers to start preventive therapy in women at higher risk. (C) 2012 Elsevier Ireland Ltd. All rights reserve

    How do children with speech sound disorders perform on language and motor skills of children compared to typically developing children?

    No full text
    Children with speech sound disorders (SSD) have speech disorders due to problems in articulation, phonology, execution (eg. dysarthria), planning (eg. apraxia), orofacial anomalies (eg. cleft palate) or hearing impairment (ASHA). How do children with speech sound disorders perform on language and motor (experimental) tests compared to typically developing children

    Individual Black-Tailed Godwits Do Not Stick to Single Routes: A Hypothesis on How Low Population Densities Might Decrease Social Conformity

    No full text
    The miniaturization of tracking devices is now rapidly increasing our knowledge on the spatiotemporal organization of seasonal migration. So far, most studies aimed at understanding within- and between-individual variation in migratory routines focus on single populations. This has also been the case for continental Black-tailed Godwits Limosa l. limosa (hereafter Godwits), with most work carried out on individuals from the Dutch breeding population, migrating in relatively large numbers in the westernmost part of the range. Here we report the migratory timing and routes of four adult individuals of the same subspecies from the low-density population in eastern Poland and compare this with previously published data on Godwits breeding in The Netherlands. During northward migration, the birds from Poland departed and arrived later from their wintering and breeding grounds. However, on southward migration the Polish breeding Godwits departed earlier, but arrived one month later than the Dutch birds on their wintering grounds in sub-Saharan Africa. Despite the small sample size of tracked birds from Poland, we find a significantly higher between-individual variation in timing during southward migration in Polish Godwits as compared to the Dutch Godwits. Furthermore, not only did migratory routes differ, but the few Polish Godwits tracked showed a higher level of between- and within-individual variation in route choice during both southward and northward migration. To explain this remarkable discrepancy, we propose that the properties of transmission of social information may be different between Godwits from a high-density population (i.e. the one in The Netherlands) and a low-density population (in Poland) and that this leads to different levels of canalization. To examine this hypothesis, future studies should not only follow individuals from an early age onwards, but also quantify and experimentally manipulate their social environments during migration

    Trends in preterm birth in singleton deliveries in a Hong Kong population

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    To examine trends in preterm birth and its relationship with perinatal mortality in Hong Kong. In a retrospective cohort study, data were reviewed from singletons delivered between 1995 and 2011 at a university teaching hospital. Trends in preterm birth (between 24 and 36 weeks of pregnancy), perinatal mortality, and subtypes of preterm birth (spontaneous, iatrogenic, and following preterm premature rupture of membranes [PPROM]) were examined via linear regression. There were 103 364 singleton deliveries, of which 6722 (6.5%) occurred preterm, including 1835 (1.8%) early preterm births (24-33 weeks) and 4887 (4.7%) late preterm births (34-36 weeks). Frequency of preterm birth remained fairly consistent over the study period, but that of spontaneous preterm birth decreased by 25% (β=-0.83; P <0.001), from 4.5% to 3.8%. Frequency of preterm birth following PPROM increased by 135% (β=0.82; P <0.001), from 0.7% to 1.7%. The perinatal mortality rate decreased from 56.7 to 37.0 deaths per 1000 deliveries before 37 weeks (β=-0.16; P=0.54). Early preterm birth contributed to 16.0% of all deaths. Although the overall rate of preterm birth in Hong Kong has remained constant, the frequencies of its subtypes have changed. Overall perinatal mortality is gradually decreasing, but early preterm birth remains a major contributo
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