Institution
Leiden University
Education•Leiden, Netherlands•
About: Leiden University is a education organization based out in Leiden, Netherlands. It is known for research contribution in the topics: Population & Galaxy. The organization has 33604 authors who have published 72681 publications receiving 3274265 citations. The organization is also known as: University of Leiden & Universiteit Leiden.
Topics: Population, Galaxy, Star formation, Redshift, Stellar mass
Papers published on a yearly basis
Papers
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TL;DR: Findings show that the baseline activity of the brain is consistent across subjects exhibiting significant temporal dynamics, with percentage BOLD signal change comparable with the signal changes found in task-related experiments.
Abstract: Functional MRI (fMRI) can be applied to study the functional connectivity of the human brain. It has been suggested that fluctuations in the blood oxygenation level-dependent (BOLD) signal during rest reflect the neuronal baseline activity of the brain, representing the state of the human brain in the absence of goal-directed neuronal action and external input, and that these slow fluctuations correspond to functionally relevant resting-state networks. Several studies on resting fMRI have been conducted, reporting an apparent similarity between the identified patterns. The spatial consistency of these resting patterns, however, has not yet been evaluated and quantified. In this study, we apply a data analysis approach called tensor probabilistic independent component analysis to resting-state fMRI data to find coherencies that are consistent across subjects and sessions. We characterize and quantify the consistency of these effects by using a bootstrapping approach, and we estimate the BOLD amplitude modulation as well as the voxel-wise cross-subject variation. The analysis found 10 patterns with potential functional relevance, consisting of regions known to be involved in motor function, visual processing, executive functioning, auditory processing, memory, and the so-called default-mode network, each with BOLD signal changes up to 3%. In general, areas with a high mean percentage BOLD signal are consistent and show the least variation around the mean. These findings show that the baseline activity of the brain is consistent across subjects exhibiting significant temporal dynamics, with percentage BOLD signal change comparable with the signal changes found in task-related experiments.
4,135 citations
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Wellcome Trust Sanger Institute1, Broad Institute2, University of Groningen3, University of Pittsburgh4, Cedars-Sinai Medical Center5, Yale University6, University of Cambridge7, University of Chicago8, Harvard University9, Katholieke Universiteit Leuven10, University of Liège11, King's College London12, Université de Montréal13, New Jersey Institute of Technology14, Cleveland Clinic15, Peninsula College of Medicine and Dentistry16, Université libre de Bruxelles17, Aarhus University18, University of Adelaide19, University of Kiel20, Flinders University21, McGill University22, Ludwig Maximilian University of Munich23, Charité24, Icahn School of Medicine at Mount Sinai25, University of Bonn26, Karolinska Institutet27, Torbay Hospital28, University of Auckland29, Christchurch Hospital30, Imperial College London31, Queen's University32, University of Oslo33, Lithuanian University of Health Sciences34, Emory University35, Casa Sollievo della Sofferenza36, Ghent University37, University of Western Australia38, University of Edinburgh39, Queensland Health40, Newcastle University41, University of Dundee42, University of Manchester43, University of Amsterdam44, University of Maribor45, Royal Hospital for Sick Children46, Guy's and St Thomas' NHS Foundation Trust47, QIMR Berghofer Medical Research Institute48, Norfolk and Norwich University Hospital49, Leiden University50, Technische Universität München51, University of Toronto52, University of Pennsylvania53, Johns Hopkins University54, University of Queensland55
TL;DR: A meta-analysis of Crohn’s disease and ulcerative colitis genome-wide association scans is undertaken, followed by extensive validation of significant findings, with a combined total of more than 75,000 cases and controls.
Abstract: Crohn's disease and ulcerative colitis, the two common forms of inflammatory bowel disease (IBD), affect over 2.5 million people of European ancestry, with rising prevalence in other populations. Genome-wide association studies and subsequent meta-analyses of these two diseases as separate phenotypes have implicated previously unsuspected mechanisms, such as autophagy, in their pathogenesis and showed that some IBD loci are shared with other inflammatory diseases. Here we expand on the knowledge of relevant pathways by undertaking a meta-analysis of Crohn's disease and ulcerative colitis genome-wide association scans, followed by extensive validation of significant findings, with a combined total of more than 75,000 cases and controls. We identify 71 new associations, for a total of 163 IBD loci, that meet genome-wide significance thresholds. Most loci contribute to both phenotypes, and both directional (consistently favouring one allele over the course of human history) and balancing (favouring the retention of both alleles within populations) selection effects are evident. Many IBD loci are also implicated in other immune-mediated disorders, most notably with ankylosing spondylitis and psoriasis. We also observe considerable overlap between susceptibility loci for IBD and mycobacterial infection. Gene co-expression network analysis emphasizes this relationship, with pathways shared between host responses to mycobacteria and those predisposing to IBD.
4,094 citations
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TL;DR: The spectrum of microsatellite alterations in noncolonic tumors was reviewed, and it was concluded that the above recommendations apply only to colorectal neoplasms.
Abstract: In December 1997, the National Cancer Institute sponsored "The International Workshop on Microsatellite Instability and RER Phenotypes in Cancer Detection and Familial Predisposition," to review and unify the field. The following recommendations were endorsed at the workshop. (a) The form of genomic instability associated with defective DNA mismatch repair in tumors is to be called microsatellite instability (MSI). (b) A panel of five microsatellites has been validated and is recommended as a reference panel for future research in the field. Tumors may be characterized on the basis of: high-frequency MSI (MSI-H), if two or more of the five markers show instability (i.e., have insertion/deletion mutations), and low-frequency MSI (MSI-L), if only one of the five markers shows instability. The distinction between microsatellite stable (MSS) and low frequency MSI (MSI-L) can only be accomplished if a greater number of markers is utilized. (c) A unique clinical and pathological phenotype is identified for the MSI-H tumors, which comprise approximately 15% of colorectal cancers, whereas MSI-L and MSS tumors appear to be phenotypically similar. MSI-H colorectal tumors are found predominantly in the proximal colon, have unique histopathological features, and are associated with a less aggressive clinical course than are stage-matched MSI-L or MSS tumors. Preclinical models suggest the possibility that these tumors may be resistant to the cytotoxicity induced by certain chemotherapeutic agents. The implications for MSI-L are not yet clear. (d) MSI can be measured in fresh or fixed tumor specimens equally well; microdissection of pathological specimens is recommended to enrich for neoplastic tissue; and normal tissue is required to document the presence of MSI. (e) The "Bethesda guidelines," which were developed in 1996 to assist in the selection of tumors for microsatellite analysis, are endorsed. (f) The spectrum of microsatellite alterations in noncolonic tumors was reviewed, and it was concluded that the above recommendations apply only to colorectal neoplasms. (g) A research agenda was recommended.
4,022 citations
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TL;DR: It is shown that in certain special cases one can easily compute or estimate the expected number of secondary cases produced by a typical infected individual during its entire period of infectiousness in a completely susceptible population.
Abstract: The expected number of secondary cases produced by a typical infected individual during its entire period of infectiousness in a completely susceptible population is mathematically defined as the dominant eigenvalue of a positive linear operator. It is shown that in certain special cases one can easily compute or estimate this eigenvalue. Several examples involving various structuring variables like age, sexual disposition and activity are presented.
3,885 citations
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Federal University of Bahia1, McMaster University2, University of Amsterdam3, National Institutes of Health4, Charité5, Catholic University of Cordoba6, University of Genoa7, Radboud University Nijmegen8, Transilvania University of Brașov9, Ghent University10, University of Tennessee Health Science Center11, University of Naples Federico II12, Laval University13, Universidade Federal de Minas Gerais14, University of Oslo15, University of Manchester16, Aarhus University17, Imperial College London18, Erasmus University Rotterdam19, George Washington University20, Seoul National University21, Medical University of Łódź22, Hai phong University Of Medicine and Pharmacy23, Université de Montréal24, Guangzhou Medical University25, University of South Florida26, University of California, San Diego27, University of California28, University of Chicago29, Monash University30, Teikyo University31, National and Kapodistrian University of Athens32, Nippon Medical School33, Sofia Medical University34, Leiden University35, Leiden University Medical Center36, University College London37, University of Manitoba38, University of Helsinki39, Finnish Institute of Occupational Health40, National University of Singapore41, Karolinska Institutet42, University of Minnesota43, Celal Bayar University44, University of Cape Town45, Pierre-and-Marie-Curie University46, Tunis University47, University of Ghana48, University of Wisconsin-Madison49, University of British Columbia50, Georgia Regents University51, Vilnius University52, University of Washington53, University of Dundee54, University of Poitiers55, University of Mississippi56, Federal University of São Paulo57, German Red Cross58, Jagiellonian University Medical College59, Chiba University60, American Pharmacists Association61, University of Aberdeen62, University of Nevada, Reno63, University of North Carolina at Chapel Hill64
TL;DR: The ARIA guidelines for the management of allergic rhinitis and asthma are similar in both the 1999 ARIA workshop report and the 2008 Update as discussed by the authors, but the GRADE approach is not yet available.
Abstract: Allergic rhinitis is a symptomatic disorder of the nose induced after allergen exposure by an IgE-mediated inflammation of the membranes lining the nose. It is a global health problem that causes major illness and disability worldwide. Over 600 million patients from all countries, all ethnic groups and of all ages suffer from allergic rhinitis. It affects social life, sleep, school and work and its economic impact is substantial. Risk factors for allergic rhinitis are well identified. Indoor and outdoor allergens as well as occupational agents cause rhinitis and other allergic diseases. The role of indoor and outdoor pollution is probably very important, but has yet to be fully understood both for the occurrence of the disease and its manifestations.
In 1999, during the Allergic Rhinitis and its Impact on Asthma (ARIA) WHO workshop, the expert panel proposed a new classification for allergic rhinitis which was subdivided into 'intermittent' or 'persistent' disease.
This classification is now validated. The diagnosis of allergic rhinitis is often quite easy, but in some cases it may cause problems and many patients are still under-diagnosed, often because they do not perceive the symptoms of rhinitis as a disease impairing their social life, school and work.
The management of allergic rhinitis is well established and the ARIA expert panel based its recommendations on evidence using an extensive review of the literature available up to December 1999. The statements of evidence for the development of these guidelines followed WHO rules and were based on those of Shekelle et al. A large number of papers have been published since 2000 and are extensively reviewed in the 2008 Update using the same evidence-based system. Recommendations for the management of allergic rhinitis are similar in both the ARIA workshop report and the 2008 Update. In the future, the GRADE approach will be used, but is not yet available.
Another important aspect of the ARIA guidelines was to consider co-morbidities. Both allergic rhinitis and asthma are systemic inflammatory conditions and often co-exist in the same patients. In the 2008 Update, these links have been confirmed.
The ARIA document is not intended to be a standard-of-care document for individual countries. It is provided as a basis for physicians, health care professionals and organizations involved in the treatment of allergic rhinitis and asthma in various countries to facilitate the development of relevant local standard-of-care documents for patients.
3,769 citations
Authors
Showing all 33963 results
Name | H-index | Papers | Citations |
---|---|---|---|
Albert Hofman | 267 | 2530 | 321405 |
Paul M. Ridker | 233 | 1242 | 245097 |
André G. Uitterlinden | 199 | 1229 | 156747 |
Cornelia M. van Duijn | 183 | 1030 | 146009 |
Valentin Fuster | 179 | 1462 | 185164 |
Brenda W.J.H. Penninx | 170 | 1139 | 119082 |
Sidney C. Smith | 169 | 467 | 267569 |
Elliott M. Antman | 161 | 716 | 179462 |
Monique M.B. Breteler | 159 | 546 | 93762 |
Lex M. Bouter | 158 | 767 | 103034 |
Caroline S. Fox | 155 | 599 | 138951 |
Fernando Rivadeneira | 146 | 628 | 86582 |
Markus Ackermann | 146 | 610 | 71071 |
Matt J. Jarvis | 144 | 1064 | 85559 |
Jacques Banchereau | 143 | 634 | 99261 |