A Growth Curve Model with Fractional Polynomials for Analysing Incomplete Time-Course Data in Microarray Gene Expression Studies

Identifying the various gene expression response patterns is a challenging issue in expression microarray time-course experiments. Due to heterogeneity in the regulatory reaction among thousands of genes tested, it is impossible to manually characterize a parametric form for each of the time-course pattern in a gene by gene manner. We introduce a growth curve model with fractional polynomials to automatically capture the various time-dependent expression patterns and meanwhile efficiently handle missing values due to incomplete observations. For each gene, our procedure compares the performances among fractional polynomial models with power terms from a set of fixed values that offer a wide range of curve shapes and suggests a best fitting model. After a limited simulation study, the model has been applied to our human in vivo irritated epidermis data with missing observations to investigate time-dependent transcriptional responses to a chemical irritant. Our method was able to identify the various nonlinear time-course expression trajectories. The integration of growth curves with fractional polynomials provides a flexible way to model different time-course patterns together with model selection and significant gene identification strategies that can be applied in microarray-based time-course gene expression experiments with missing observations

Association between topical corticosteroid use and type 2 diabetes in two European population-based adult cohorts

BackgroundTopical corticosteroids (CS) are commonly used to treat inflammatory skin conditions including eczema and psoriasis. While topical CS package inserts describe hyperglycaemia and glycosuria as adverse drug reactions, it is unclear whether topical CS use in real life is also associated with an increased risk of type 2 diabetes (T2D).MethodsTwo matched case-control studies and one cohort study were conducted using routinely collected healthcare data from Denmark the UK. A total of 115,218 and 54,944 adults were identified as cases with new onset T2D in the Danish and UK case-control study, respectively. For the Danish cohort study, 2,689,473 adults were included. The main exposure was topical CS and the outcome was incident T2D.ResultsTopical CS was significantly associated with T2D in the Danish (adjusted OR 1ꞏ35; 95% CI 1ꞏ33- 1ꞏ38) and UK (adjusted OR 1ꞏ23; 95% CI 1ꞏ19-1ꞏ27) case-control studies. Individuals who were exposed to topical CS had significantly increased risk of incident T2D (adjusted HR 1ꞏ27; 95% CI 1ꞏ26-1ꞏ29). We observed significant dose-response relationships between T2D and increasing potency of topical CS in the two Danish studies. The results were consistent across all sensitivity analyses.ConclusionsWe found a positive association between topical CS prescribing and incident T2D in Danish and UK adult populations. Clinicians should be cognizant of possible diabetogenic effects of potent topical CS

Distribution of cholinergic nerve terminals in the aged human brain measured with [18F]FEOBV PET and its correlation with histological data

Introduction: [18F]fluoroetoxybenzovesamicol ([18F]FEOBV) is a positron emission topography (PET) tracer for the vesicular acetylcholine transporter (VAChT), a protein located predominantly in synaptic vesicles in cholinergic nerve terminals. We aimed to use [18F]FEOBV PET to study the cholinergic topography of the healthy human brain. Materials and methods: [18F]FEOBV PET brain data volumes of healthy elderly humans were normalized to standard space and intensity-normalized to the white matter. Stereotactic atlases of regions of interest were superimposed to describe and quantify tracer distribution. The spatial distribution of [18F]FEOBV PET uptake was compared with histological and gene expression data. Results: Twenty participants of both sexes and a mean age of 73.9 ± 6.0 years, age-range [64; 86], were recruited. Highest tracer binding was present in the striatum, some thalamic nuclei, and the basal forebrain. Intermediate binding was found in most nuclei of the brainstem, thalamus, and hypothalamus; the vermis and flocculonodular lobe; and the hippocampus, amygdala, insula, cingulate, olfactory cortex, and Heschl's gyrus. Lowest binding was present in most areas of the cerebral cortex, and in the cerebellar nuclei and hemispheres. The spatial distribution of tracer correlated with immunohistochemical post-mortem data, as well as with regional expression levels of SLC18A3, the VAChT coding gene. Discussion: Our in vivo findings confirm the regional cholinergic distribution in specific brain structures as described post-mortem. A positive spatial correlation between tracer distribution and regional gene expression levels further corroborates [18F]FEOBV PET as a validated tool for in vivo cholinergic imaging. The study represents an advancement in the continued efforts to delineate the spatial topography of the human cholinergic system in vivo

Risk of heart failure among individuals tested for Borrelia burgdorferi sensu lato antibodies, and serum Borrelia burgdorferi sensu lato seropositive individuals; a nationwide population-based, registry-based matched cohort study

BACKGROUND: Lyme borreliosis is a tick-borne disease caused by the bacterium Borrelia burgdorferi (Bb) sensu lato complex. Previous studies have suggested an association between Lyme borreliosis and heart failure, which have been suggested to be a possible manifestation of Lyme carditis. We aimed to investigate the risk of heart failure among individuals tested for serum Bb antibodies, and serum Bb seropositive individuals.METHODS: We performed a matched nationwide cohort study (Denmark, 1993-2020) and included 52,200 Bb seropositive individuals, and two age- and sex-matched comparison cohorts: 1) 104,400 Bb seronegative comparison cohort members, and 2) 261,000 population controls. We investigated the risk associated with 1) being tested for serum Bb antibodies, and 2) being Bb seropositive. Outcomes were: 1) a composite of heart failure, cardiomyopathy, and/or myocarditis diagnosis, and 2) redemption of cardiovascular medicine used for treatment of heart failure. We calculated short-term odds ratios (aOR) (within 1 month) and long-term hazard rates (aHR) (after 1 month) adjusted for age, sex, diabetes, pre-existing heart failure, and kidney disease.RESULTS: Compared with the population controls, individuals tested for Bb antibodies, regardless of the test result, had increased short-term risk of heart failure, cardiomyopathy, and myocarditis (aOR 8.3, 95 %CI: 6.7-10.2), and both increased short- and long-term risk of redemption of cardiovascular medicine (aOR 4.3, 95 %CI: 3.8-4.8, aHR 1.13, 95 % CI: 1.11-1.15). The Bb seropositive individuals had no increased short- or long-term risk of any outcome compared with Bb seronegative comparison cohort members.CONCLUSIONS: In conclusion, Bb antibody tests seemed to be performed in the diagnostic work-up of heart failure, but Bb seropositivity was not associated with heart failure.</p

Use of benzodiazepines and benzodiazepine-related drugs in the Nordic countries between 2000 and 2020

Funding Information: MH was supported by a grant from the Mental Health Services in the Region of Southern Denmark during the conduct of this study. HZ was supported by a UNSW Scientia Program Award during the conduct of this study. JWW was supported by a grant from Riksbankens Jubileumsfond during the conduct of this study. Publisher Copyright: © 2022 The Authors. Basic & Clinical Pharmacology & Toxicology published by John Wiley & Sons Ltd on behalf of Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).Use of benzodiazepines (BZ) and related drugs is subject to considerable debate due to problems with dependency and adverse events. We aimed to describe and compare their use across the Nordic countries. Data on the use of clonazepam, BZ-sedatives, BZ-hypnotics, and benzodiazepine-related drugs (BZRD) in adults (≥20 years) were obtained from nationwide registers in Denmark, Finland, Iceland, Norway, and Sweden, 2000–2020. Main measures were therapeutic intensity (TI:DDD/1000 inhabitants [inhab.]/day) and annual prevalence (users/1000 inhab./year). Overall, TI of BZ and related drugs decreased in all Nordic countries from 2004 to 2020. However, there were considerable differences between countries in TI. In 2020, the TI of BZ and related drugs ranged from 17 DDD/1000 inhab./day in Denmark to 93 DDD/1000 inhab./day in Iceland. BZRD accounted for 55–78% of BZ use in 2020, followed by BZ sedatives at 20–44%, BZ-hypnotics at <1–5%, and clonazepam at <1–2%. Annual prevalence of BZ use increased with age in all countries, and the highest annual prevalence was observed among people ≥80 years. Overall, the use of BZ and related drugs has decreased in all Nordic countries from 2004 to 2020, however, with considerable differences in their use between countries. The highest prevalence was observed among the oldest age groups—despite warnings against their use in this population.Peer reviewe