Lars M.T. Eijssen

Dr. Lars M.T. Eijssen

orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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24 April 2013 in Nucleic Acids Research
Verified
Journal Article
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LELars M.T. Eijssen
Lars M.T. Eijssen
MJMagali Jaillard
Magali Jaillard
Michiel AdriaensMichiel Adriaens
Michiel Adriaens
SGStan Gaj
Stan Gaj
PGPhilip J. de Groot
Philip J. de Groot
CEChris T Evelo
Chris T Evelo
Quality control (QC) is crucial for any scientific method producing data. Applying adequate QC introduces new challenges in the genomics field where large amounts of data are produced with complex technologies. For DNA microarrays, specific algorithms for QC and pre-processing including normalization have been developed by the scientific community, especially for expression chips of the Affymetrix platform. Many of these have been implemented in the statistical scripting language R and are available from the Bioconductor repository. However, application is hampered by lack of integrative tools that can be used by users of any experience level. To fill this gap, we developed a freely available tool for QC and pre-processing of Affymetrix gene expression results, extending, integrating and harmonizing functionality of Bioconductor packages. The tool can be easily accessed through a wizard-like web portal at http://www.arrayanalysis.org or downloaded for local use in R. The portal provides extensive documentation, including user guides, interpretation help with real output illustrations and detailed technical documentation. It assists newcomers to the field in performing state-of-the-art QC and pre-processing while offering data analysts an integral open-source package. Providing the scientific community with this easily accessible tool will allow improving data quality and reuse and adoption of standards.

Verified
Journal Article
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GJGhazi I. Al Jowf
Ghazi I. Al Jowf
ZAZiyad T. Ahmed
Ziyad T. Ahmed
RRRick A. Reijnders
Rick A. Reijnders
LNLaurence de Nijs
Laurence de Nijs
LELars M.T. Eijssen
Lars M.T. Eijssen
Post-traumatic stress disorder (PTSD) can become a chronic and severely disabling condition resulting in a reduced quality of life and increased economic burden. The disorder is directly related to exposure to a traumatic event, e.g., a real or threatened injury, death, or sexual assault. Extensive research has been done on the neurobiological alterations underlying the disorder and its related phenotypes, revealing brain circuit disruption, neurotransmitter dysregulation, and hypothalamic–pituitary–adrenal (HPA) axis dysfunction. Psychotherapy remains the first-line treatment option for PTSD given its good efficacy, although pharmacotherapy can also be used as a stand-alone or in combination with psychotherapy. In order to reduce the prevalence and burden of the disorder, multilevel models of prevention have been developed to detect the disorder as early as possible and to reduce morbidity in those with established diseases. Despite the clinical grounds of diagnosis, attention is increasing to the discovery of reliable biomarkers that can predict susceptibility, aid diagnosis, or monitor treatment. Several potential biomarkers have been linked with pathophysiological changes related to PTSD, encouraging further research to identify actionable targets. This review highlights the current literature regarding the pathophysiology, disease development models, treatment modalities, and preventive models from a public health perspective, and discusses the current state of biomarker research.

1 October 2021 in Molecular Systems Biology
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Journal Article
Open access
MOMarek Ostaszewski
Marek Ostaszewski
Anna NiarakisAnna Niarakis
Anna Niarakis
AMAlexander Mazein
Alexander Mazein
IKInna Kuperstein
Inna Kuperstein
RPRobert Phair
Robert Phair
RSReinhard Schneider
Reinhard Schneider
We need to effectively combine the knowledge from surging literature with complex datasets to propose mechanistic models of SARS‐CoV‐2 infection, improving data interpretation and predicting key targets of intervention. Here, we describe a large‐scale community effort to build an open access, interoperable and computable repository of COVID‐19 molecular mechanisms. The COVID‐19 Disease Map (C19DMap) is a graphical, interactive representation of disease‐relevant molecular mechanisms linking many knowledge sources. Notably, it is a computational resource for graph‐based analyses and disease modelling. To this end, we established a framework of tools, platforms and guidelines necessary for a multifaceted community of biocurators, domain experts, bioinformaticians and computational biologists. The diagrams of the C19DMap, curated from the literature, are integrated with relevant interaction and text mining databases. We demonstrate the application of network analysis and modelling approaches by concrete examples to highlight new testable hypotheses. This framework helps to find signatures of SARS‐CoV‐2 predisposition, treatment response or prioritisation of drug candidates. Such an approach may help deal with new waves of COVID‐19 or similar pandemics in the long‐term perspective.

GJGhazi I. Al Jowf
Ghazi I. Al Jowf
ZAZiyad T. Ahmed
Ziyad T. Ahmed
NANing An
Ning An
RRRick A. Reijnders
Rick A. Reijnders
Elena AmbrosinoElena Ambrosino
Elena Ambrosino
LELars M.T. Eijssen
Lars M.T. Eijssen
Trauma exposure is one of the most important and prevalent risk factors for mental and physical ill-health. Prolonged or excessive stress exposure increases the risk of a wide variety of mental and physical symptoms, resulting in a condition known as post-traumatic stress disorder (PTSD). The diagnosis might be challenging due to the complex pathophysiology and co-existence with other mental disorders. The prime factor for PTSD development is exposure to a stressor, which variably, along with peritraumatic conditions, affects disease progression and severity. Additionally, many factors are thought to influence the response to the stressor, and hence reshape the natural history and course of the disease. With sufficient knowledge about the disease, preventive and intervenient methods can be implemented to improve the quality of life of the patients and to limit both the medical and economic burden of the disease. This literature review provides a highlight of up-to-date literature on traumatic stress, with a focus on causes or triggers of stress, factors that influence response to stress, disease burden, and the application of the social-ecological public health model of disease prevention. In addition, it addresses therapeutic aspects, ethnic differences in traumatic stress, and future perspectives, including potential biomarkers.

28 July 2022 in Molecular Psychiatry
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YZYentl Y. van der Zee
Yentl Y. van der Zee
LELars M.T. Eijssen
Lars M.T. Eijssen
PMPhilipp Mews
Philipp Mews
ARAarthi Ramakrishnan
Aarthi Ramakrishnan
KAKelvin Alvarez
Kelvin Alvarez
OIOrna Issler
Orna Issler

7 November 2022 in npj Parkinson's Disease
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Journal Article
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JHJoshua Harvey
Joshua Harvey
RRRick A. Reijnders
Rick A. Reijnders
RCRachel Cavill
Rachel Cavill
ADAnnelien Duits
Annelien Duits
SKSebastian Köhler
Sebastian Köhler
EPEhsan Pishva
Ehsan Pishva
Cognitive impairment is a debilitating symptom in Parkinson’s disease (PD). We aimed to establish an accurate multivariate machine learning (ML) model to predict cognitive outcome in newly diagnosed PD cases from the Parkinson’s Progression Markers Initiative (PPMI). Annual cognitive assessments over an 8-year time span were used to define two cognitive outcomes of (i) cognitive impairment, and (ii) dementia conversion. Selected baseline variables were organized into three subsets of clinical, biofluid and genetic/epigenetic measures and tested using four different ML algorithms. Irrespective of the ML algorithm used, the models consisting of the clinical variables performed best and showed better prediction of cognitive impairment outcome over dementia conversion. We observed a marginal improvement in the prediction performance when clinical, biofluid, and epigenetic/genetic variables were all included in one model. Several cerebrospinal fluid measures and an epigenetic marker showed high predictive weighting in multiple models when included alongside clinical variables.