Per- and polyfluoroalkyl substances (PFAS) are widely used and persistent chemicals, leading to ubiquitous exposure. Although high PFAS levels have been associated with an adverse cardiovascular... Show morePer- and polyfluoroalkyl substances (PFAS) are widely used and persistent chemicals, leading to ubiquitous exposure. Although high PFAS levels have been associated with an adverse cardiovascular risk profile, the distribution of levels and relations with cardio-metabolic risk markers in the general population have not been fully characterized. We assessed the association between blood levels of perfluorooctaneic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and perfluorohexanesulfonic acid (PFHxS) and a range of lipoproteins and metabolites as well as clinical lipid measurements. We used data from participants of the Netherlands Epidemiology of Obesity study (NEO) (n = 584) and the Rhineland Study (n = 1962), jointly spanning an age range of 30 to 89 years. PFAS were measured with the Metabolon HD4 platform, and lipoprotein and metabolite profiles were measured using Nightingale's nuclear magnetic resonance-spectroscopy platform, and mainly comprised lipoprotein markers. Using linear regression analyses, we quantified age-, sex-, and education-adjusted associations of PFOA, PFOS, and PFHxS with clinical lipid measurements and 224 lipoproteins and metabolites. Higher levels of PFAS, particularly PFOS and PFHxS, were associated with higher concentrations of total lipid, cholesterol and phospholipid content in most HDL, IDL, LDL, and VLDL subclasses. The effect sizes were age-dependent for the majority of the associations, with the deleterious effects of PFAS being generally stronger in people below compared to those above median age. Our observation that in the general population even low PFAS concentrations are associated with an unfavorable lipid profile, calls for further critical regulation of PFAS substances. Show less
Introduction The empty pelvis syndrome is a significant source of morbidity following pelvic exenteration surgery. It remains poorly defined with research in this field being heterogeneous and of... Show moreIntroduction The empty pelvis syndrome is a significant source of morbidity following pelvic exenteration surgery. It remains poorly defined with research in this field being heterogeneous and of low quality. Furthermore, there has been minimal engagement with patient representatives following pelvic exenteration with respect to the empty pelvic syndrome. ‘PelvEx—Beating the empty pelvis syndrome’ aims to engage both patient representatives and healthcare professionals to achieve an international consensus on a core outcome set, pathophysiology and mitigation of the empty pelvis syndrome. Methods and analysis A modified-Delphi approach will be followed with a three-stage study design. First, statements will be longlisted using a recent systematic review, healthcare professional event, patient and public engagement, and Delphi piloting. Second, statements will be shortlisted using up to three rounds of online modified Delphi. Third, statements will be confirmed and instruments for measurable statements selected using a virtual patient-representative consensus meeting, and finally a face-to-face healthcare professional consensus meeting. Ethics and dissemination The University of Southampton Faculty of Medicine ethics committee has approved this protocol, which is registered as a study with the Core Outcome Measures in Effectiveness Trials Initiative. Publication of this study will increase the potential for comparative research to further understanding and prevent the empty pelvis syndrome.Trial registration number NCT05683795. Show less
Tandem cytosine-adenine-guanine (CAG) repeat sizes of 36 or more in the huntingtin gene (HTT) cause Huntington's disease (HD). Apart from neuropsychiatric complications, the disease is also... Show moreTandem cytosine-adenine-guanine (CAG) repeat sizes of 36 or more in the huntingtin gene (HTT) cause Huntington's disease (HD). Apart from neuropsychiatric complications, the disease is also accompanied by metabolic dysregulation and weight loss, which contribute to a progressive functional decline. Recent studies also reported an association between repeats below the pathogenic threshold (<36) for HD and body mass index (BMI), suggesting that HTT repeat sizes in the non-pathogenic range are associated with metabolic dysregulation. In this study, we hypothesized that HTT repeat sizes < 36 are associated with metabolite levels, possibly mediated through reduced BMI. We pooled data from three European cohorts (n = 10 228) with genotyped HTT CAG repeat size and metabolomic measurements. All 145 metabolites were measured on the same targeted platform in all studies. Multilevel mixed-effects analysis using the CAG repeat size in HTT identified 67 repeat size metabolite associations. Overall, the metabolomic profile associated with larger CAG repeat sizes in HTT were unfavorable-similar to those of higher risk of coronary artery disease and type 2 diabetes-and included elevated levels of amino acids, fatty acids, low-density lipoprotein (LDL)-, very low-density lipoprotein- and intermediate density lipoprotein (IDL)-related metabolites while with decreased levels of very large high-density lipoprotein (HDL)-related metabolites. Furthermore, the associations of 50 metabolites, in particular, specific very large HDL-related metabolites, were mediated by lower BMI. However, no mediation effect was found for 17 metabolites related to LDL and IDL. In conclusion, our findings indicate that large non-pathogenic CAG repeat sizes in HTT are associated with an unfavorable metabolomic profile despite their association with a lower BMI. Show less
The surge in the number of authors per article in the biomedical field makes it difficult to quantify the contribution of individual authors. Conventional citation metrics are typically based on... Show moreThe surge in the number of authors per article in the biomedical field makes it difficult to quantify the contribution of individual authors. Conventional citation metrics are typically based on the number of publications and the number of citations generated by a scientist, thereby disregarding the contribution of co-authors. Previously we developed the p-index that estimates the dependency of a scientist on co-authors during their career. In this study we aimed to evaluate the ability of the p-index to identify researchers with a relatively high degree of scientific dependence on co-authors. For this purpose, we retrieved articles, which were rejected for publication in Journal of Thrombosis and Haemostasis and subsequently published elsewhere. Assuming that authors who were added to a later version of these articles would not fulfill the full authorship criteria, we tested whether these authors showed a larger dependency on co-authors during their scientific career as would be evident from a higher p-index. In accordance with this hypothesis, authors who were added on later versions of articles showed a higher p-index than their peers, indicating an enduring pattern of dependency on other co-authors for publishing their work. This study underscores that questionable authorship practices are endemic to the biomedical research, which calls for alternative methods to evaluate a scientist's qualities. Show less
Huntington disease (HD) is an autosomal dominant, neurodegenerative disease caused by a CAG repeat expansion within the coding sequence of the HTT gene, resulting in a highly toxic protein with an... Show moreHuntington disease (HD) is an autosomal dominant, neurodegenerative disease caused by a CAG repeat expansion within the coding sequence of the HTT gene, resulting in a highly toxic protein with an expanded polyglutamine stretch that forms typical protein aggregates throughout the brain. We generated human induced pluripotent stem cells (hiPSCs) from two HD patients using non-integrating Sendai virus (SeV). The hiPSCs display a normal karyotype, express all pluripotency markers, have the same CAG repeat expansion as the original fibroblasts and are able to differentiate into the three germ layers in vitro. Show less
Objective: Our aim was to determine the prognostic significance of the systemic-immune-inflammation index (SIII) in patients with resectable pancreatic cancer, using cancer-specific survival as the... Show moreObjective: Our aim was to determine the prognostic significance of the systemic-immune-inflammation index (SIII) in patients with resectable pancreatic cancer, using cancer-specific survival as the primary outcome.Background: Pancreatic cancer is associated with a dysfunctional immune system and poor prognosis. We examined the prognostic significance of the SIII in patients with resectable pancreatic ductal adenocarcinoma (PDAC) and the effects of bilirubin on this index.Methods: We retrospectively assessed all pancreatic resections performed between 2004 and 2015 at 4 tertiary referral centers to identify pathologically confirmed PDAC patients. Baseline clinicopathologic characteristics, preoperative laboratory values such as absolute neutrophil, lymphocyte, and platelet counts, C-reactive protein, albumin, bilirubin, and CA19-9 levels, and also follow-up information, were collected. The associations of the calculated inflammatory indices with outcome were both internally and externally validated.Results: In all, 590 patients with resectable PDAC were included. The discovery and validation cohort included 170 and 420 patients, respectively. SIII > 900 [hazard ratio (HR) 2.32, 95% confidence interval (CI) 1.55-3.48], lymph node ratio (HR 3.75, 95% CI 2.08-6.76), and CA19.9 > 200 kU/L (HR 1.62, 95% CI 1.07-2.46) were identified as independent predictors of cancer-specific survival. Separate model analysis confirmed that preoperative SIII contributed significantly to prognostication. However, SIII appeared to lose its prognostic significance in patients with bilirubin levels above 200 mu mol/L.Conclusions: SIII is an independent predictor of cancer-specific survival and recurrence in patients with resectable PDAC. SIII may lose its prognostic significance in patients with high bilirubin levels. Properly designed prospective studies are needed to further confirm this hypothesis. Show less