132 research outputs found

    Modulation of Ischemia Reperfusion injury in kidney transplantation

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    Niertransplantatie is nog steeds de voorkeursbehandeling voor eindstadium nierfalen. Ischemie reperfusieschade is daarbij een onvermijdelijk fenomeen. Dit proefschrift is erop gericht om methode te vinden om ischemie reperfusieschade te voorkomen, danwel te verminderen. Een mogelijkheid is dieetrestrictie waarbij al is aangetoond dat calorierestrictie in muizen ischemie reperfusieschade vermindert. Echter is dit lastig te transleren naar de kliniek, waarvoor een dieetmimeticum een uitkomst zou kunnen zijn. Een deel van dit proefschrift onderzoekt Rapamycine als dieetmimeticum en onderzoekt de effecten van dieetrestrictie op microRNA niveau. Een andere methode om ischemie reperfusieschade te verminderen is het toepassen van (post) conditioning, waarbij de reperfusiefase gefaseerd wordt ingevoerd. Er is een feasibility studie verricht bij ontvangers van een DCD niertransplantatie. Daarnaast is onderzoek verricht naar biomarkers van ischemie reperfusieschade zodat de schade zo vroeg en specifiek mogelijk gemonitored kan worden.<br/

    Rapamycin Does Not Act as a Dietary Restriction Mimetic in the Protection against Ischemia Reperfusion Injury

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    Introduction: Short-term fasting protects against renal ischemia reperfusion injury (IRI). mTOR signaling is downregulated and may be involved in its protective effect. Rapamycin is considered a possible mimetic as it inhibits the mTOR pathway. This study examines the effect of rapamycin on renal IRI. Material and Methods: Mice were divided into four groups: ad libitum (AL), fasted (F), AL treated with rapamycin (AL+R), and F treated with rapamycin (F+R). Rapamycin was administered intraperitoneally 24 h before bilateral renal IRI was induced. Survival was monitored for 7 days. Renal cell death, regeneration, and mTOR activity were determined 48 h after reperfusion. Oxidative stress resistance of human renal proximal tubular and human primary tubular epithelial cells after rapamycin treatment was determined. Results: All F and F+R mice survived the experiment. Although rapamycin substantially downregulated mTOR activity, survival in the AL+R group was similar to AL (10%). Renal regeneration was significantly reduced in AL+R but not in F+R. After IRI (48 h), pS6K/S6K ratio was lower in F, F+R, and AL+R groups compared to AL fed animals (p = 0.02). In vitro, rapamycin also significantly downregulated mTOR activity (p &lt; 0.001) but did not protect against oxidative stress. Conclusion: Rapamycin pretreatment does not protect against renal IRI. Thus, protection against renal IRI by fasting is not exclusively mediated through inhibition of mTOR activity but may involve preservation of regenerative mechanisms despite mTOR downregulation. Therefore, rapamycin cannot be used as a dietary mimetic to protect against renal IRI.</p

    An economic analysis of patient controlled remifentanil and epidural analgesia as pain relief in labour (RAVEL trial) : A randomised controlled trial.

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    Data Availability: The original full data set included possible identifying information (birthdates and patient initials). A edited dataset without these variables is uploaded with this submission. For access to the full and original data set including birthdates and initials Liv Freeman or Johanna Middeldorp can be contacted. Access to the original case report form can also be requested. Funding: Financial support for this trial was provided by ZonMW (Dutch Organization for Health Care Research and Development), the Hague, the Netherlands, project number 80-82310-97-11039. www.zonmw.nl. The grant applicant was JM, the funding was transfered to the Leiden University Medical Center. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewe

    Underlying molecular mechanisms of DIO2 susceptibility in symptomatic osteoarthritis

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    Objectives: To investigate how the genetic susceptibility gene DIO2 confers risk to osteoarthritis (OA) onset in humans and to explore whether counteracting the deleterious effect could contribute to novel therapeutic approaches. Methods: Epigenetically regulated expression of DIO2 was explored by assessing methylation of positional CpG-dinucleotides and the respective DIO2 expression in OA-affected and macroscopically preserved articular cartilage from end-stage OA patients. In a human in vitro chondrogenesis model, we measured the effects when thyroid signalling during culturing was either enhanced (excess T3 or lentiviral induced DIO2 overexpression) or decreased (iopanoic acid). Results: OA-related changes in methylation at a specific CpG dinucleotide upstream of DIO2 caused significant upregulation of its expression (ß=4.96; p=0.0016). This effect was enhanced and appeared driven specifically by DIO2 rs225014 risk allele carriers (ß=5.58, p=0.0006). During in vitro chondrogenesis, DIO2 overexpression resulted in a significant reduced capacity of chondrocytes to deposit extracellular matrix (ECM) components, concurrent with significant induction of ECM degrading enzymes (ADAMTS5, MMP13) and markers of mineralisation (ALPL, COL1A1). Given their concurrent and significant upregulation of expression, this process is likely mediated via HIF-2a/RUNX2 signalling. In contrast, we showed that inhibiting deiodinases during in vitro chondrogenesis contributed to prolonged cartilage homeostasis as reflected by significant increased deposition of ECM components and attenuated upregulation of matrix degrading enzymes. Conclusions: Our findings show how genetic variation at DIO2 could confer risk to OA and raised the possibility that counteracting thyroid signalling may be a novel therapeutic approach

    Development and socialization of self-regulation from infancy to adolescence:A meta-review differentiating between self-regulatory abilities, goals, and motivation

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    Self-regulation has been intensely studied across developmental science disciplines in virtue of its significance to understanding and fostering adaptive functioning throughout life. Whereas research has predominantly focused on self-regulatory abilities, age-related changes in goals and motivation that underlie self-regulation have been largely neglected. In a systematic meta-review, we disentangle the development of self-regulatory abilities from age-related goals and motivation between infancy and adolescence. We further investigate the roles of parents, teachers, and peers in the socialization of self-regulatory abilities separately from the socialization of goals and motivation. We searched reviews and meta-analyses on self-regulation in typical development (0–18 years), identifying 1,935 records, from which 136 articles were included. Results show that self-regulation develops from being largely co-regulated in infancy to an independent yet socially-calibrated process in adolescence. We further demonstrate continuity as well as age-related transitions in the abilities, goals, and motivation employed for self-regulation, and pinpoint the exact role of various social agents involved in these processes. Our meta-review yields a detailed description of self-regulation development between infancy and adolescence, providing a starting point for future developmental and intervention work regarding key processes and social agents to be considered when targeting self-regulation in a particular age group.</p

    Transcriptional Profiling of Human Familial Longevity Indicates a Role for ASF1A and IL7R

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    The Leiden Longevity Study consists of families that express extended survival across generations, decreased morbidity in middle-age, and beneficial metabolic profiles. To identify which pathways drive this complex phenotype of familial longevity and healthy aging, we performed a genome-wide gene expression study within this cohort to screen for mRNAs whose expression changes with age and associates with longevity. We first compared gene expression profiles from whole blood samples between 50 nonagenarians and 50 middle-aged controls, resulting in identification of 2,953 probes that associated with age. Next, we determined which of these probes associated with longevity by comparing the offspring of the nonagenarians (50 subjects) and the middle-aged controls. The expression of 360 probes was found to change differentially with age in members of the long-lived families. In a RT-qPCR replication experiment utilizing 312 controls, 332 offspring and 79 nonagenarians, we confirmed a nonagenarian specific expression profile for 21 genes out of 25 tested. Since only some of the offspring will have inherited the beneficial longevity profile from their long-lived parents, the contrast between offspring and controls is expected to be weak. Despite this dilution of the longevity effects, reduced expression levels of two genes, ASF1A and IL7R, involved in maintenance of chromatin structure and the immune system, associated with familial longevity already in middle-age. The size of this association increased when controls were compared to a subfraction of the offspring that had the highest probability to age healthily and become long-lived according to beneficial metabolic parameters. In conclusion, an “aging-signature” formed of 21 genes was identified, of which reduced expression of ASF1A and IL7R marked familial longevity already in middle-age. This indicates that expression changes of genes involved in metabolism, epigenetic control and immune function occur as a function of age, and some of these, like ASF1A and IL7R, represent early features of familial longevity and healthy ageing

    Remifentanil patient controlled analgesia versus epidural analgesia in labour. A multicentre randomized controlled trial

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    Contains fulltext : 109349.pdf (publisher's version ) (Open Access)ABSTRACT: BACKGROUND: Pain relief during labour is a topic of major interest in the Netherlands. Epidural analgesia is considered to be the most effective method of pain relief and recommended as first choice. However its uptake by pregnant women is limited compared to other western countries, partly as a result of non-availability due to logistic problems. Remifentanil, a synthetic opioid, is very suitable for patient controlled analgesia. Recent studies show that epidural analgesia is superior to remifentanil patient controlled analgesia in terms of pain intensity score; however there was no difference in satisfaction with pain relief between both treatments. METHODS/DESIGN: The proposed study is a multicentre randomized controlled study that assesses the cost-effectiveness of remifentanil patient controlled analgesia compared to epidural analgesia. We hypothesize that remifentanil patient controlled analgesia is as effective in improving pain appreciation scores as epidural analgesia, with lower costs and easier achievement of 24 hours availability of pain relief for women in labour and efficient pain relief for those with a contraindication for epidural analgesia.Eligible women will be informed about the study and randomized before active labour has started. Women will be randomly allocated to a strategy based on epidural analgesia or on remifentanil patient controlled analgesia when they request pain relief during labour. Primary outcome is the pain appreciation score, i.e. satisfaction with pain relief.Secondary outcome parameters are costs, patient satisfaction, pain scores (pain-intensity), mode of delivery and maternal and neonatal side effects.The economic analysis will be performed from a short-term healthcare perspective. For both strategies the cost of perinatal care for mother and child, starting at the onset of labour and ending ten days after delivery, will be registered and compared. DISCUSSION: This study, considering cost effectiveness of remifentanil as first choice analgesia versus epidural analgesia, could strongly improve the care for 180.000 women, giving birth in the Netherlands yearly by giving them access to pain relief during labour, 24 hours a day. TRIAL REGISTRATION NUMBER: Dutch Trial Register NTR2551, http://www.trialregister.nl

    Metabolomic profiles predict individual multidisease outcomes

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    Publisher Copyright: © 2022, The Author(s).Risk stratification is critical for the early identification of high-risk individuals and disease prevention. Here we explored the potential of nuclear magnetic resonance (NMR) spectroscopy-derived metabolomic profiles to inform on multidisease risk beyond conventional clinical predictors for the onset of 24 common conditions, including metabolic, vascular, respiratory, musculoskeletal and neurological diseases and cancers. Specifically, we trained a neural network to learn disease-specific metabolomic states from 168 circulating metabolic markers measured in 117,981 participants with ~1.4 million person-years of follow-up from the UK Biobank and validated the model in four independent cohorts. We found metabolomic states to be associated with incident event rates in all the investigated conditions, except breast cancer. For 10-year outcome prediction for 15 endpoints, with and without established metabolic contribution, a combination of age and sex and the metabolomic state equaled or outperformed established predictors. Moreover, metabolomic state added predictive information over comprehensive clinical variables for eight common diseases, including type 2 diabetes, dementia and heart failure. Decision curve analyses showed that predictive improvements translated into clinical utility for a wide range of potential decision thresholds. Taken together, our study demonstrates both the potential and limitations of NMR-derived metabolomic profiles as a multidisease assay to inform on the risk of many common diseases simultaneously.Peer reviewe
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