The normality assumption of measurement error is a widely used distribution in joint models of longitudinal and survival data, but it may lead to unreasonable or even misleading results when longitudinal data reveal skewness feature. This paper proposes a new joint model for multivariate longitudinal and multivariate survival data by incorporating a nonparametric function into the trajectory function and hazard function and assuming that measurement errors in longitudinal measurement models follow a skew-normal distribution. A Monte Carlo Expectation-Maximization (EM) algorithm together with the penalized-splines technique and the Metropolis-Hastings algorithm within the Gibbs sampler is developed to estimate parameters and nonparametric functions in the considered joint models. Case deletion diagnostic measures are proposed to identify the potential influential observations, and an extended local influence method is presented to assess local influence of minor perturbations. Simulation studies and a real example from a clinical trial are presented to illustrate the proposed methodologies. Copyright © 2017 John Wiley & Sons, Ltd.
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Purinergic Signal
January 2025
International Joint Research Centre On Purinergic Signalling, School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China.
In a recent article published in Nature Communications (Shigetomi et al Nat Commun 15(1):6525, 2024), Shigetomi et al. identified that upregulated astrocytic purinergic P2Y receptors (P2YR), acting via the downstream molecule, insulin-like growth factor binding protein 2 (IGFBP2), play a crucial role in neuronal hyperexcitability. In epilepsy and stroke models, P2YR-IGFBP2 signaling was found to mediate astrocyte-driven neuronal hyperexcitability and so is a new contributor to astrocyte-neuron communication.
View Article and Find Full Text PDFRheumatol Int
January 2025
Department of Internal Medicine, General Hospital Oberndorf, Teaching Hospital of the Paracelsus Medical University, Salzburg, Austria.
Rheumatoid arthritis (RA) is a chronic autoimmune disease marked by systemic inflammation. While RA primarily affects the joints, its systemic effects may lead to an increased cerebro- and cardiovascular risk. Atherosclerosis of the carotid arteries is a significant risk factor for cerebrovascular events and serves as a surrogate marker for cardiovascular risk.
View Article and Find Full Text PDFAm J Health Promot
January 2025
Institute for Behavioral and Community Health, San Diego State University, San Diego, CA, USA.
Purpose: Social support, particularly from family, is crucial for physical activity (PA) among youth. This study examined the association between father support and moderate-to-vigorous physical activity (MVPA) in Latina pre-teens and explored the moderating role of body mass index (BMI).
Design: Cross-sectional analysis.
FEBS Open Bio
January 2025
Sunny BioDiscovery Inc., Santa Paula, CA, USA.
Dimethyl fumarate (DMF) is an anti-inflammatory and immunoregulatory medication used to treat multiple sclerosis (MS) and psoriasis. Its skin sensitization property precludes its topical use, which is unfortunate for the treatment of psoriasis. Isosorbide di-(methyl fumarate) (IDMF), a novel derivative of DMF, was synthesized to circumvent this adverse reaction and unlock the potential of topical delivery, which could be useful for treating psoriasis in the subpopulation of psoriatic MS patients, as well as in the general population.
View Article and Find Full Text PDFPlant Biol (Stuttg)
January 2025
Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany.
Plant individuals within a species can differ markedly in their leaf chemical composition, forming so-called chemotypes. Little is known about whether such differences impact the microbial communities associated with leaves and how different environmental conditions may shape these relationships. We used Tanacetum vulgare as a model plant to study the impacts of maternal effects, leaf terpenoid chemotype, and the environment on the leaf bacterial community by growing plant clones in the field and a greenhouse.
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