Cross-sectional associations between serum PFASs and inflammatory biomarkers in a population exposed to AFFF-contaminated drinking water

Background: Per- and polyfluoroalkyl substances (PFASs) are widespread and persistent environmental contaminants. Exposure to several PFASs has been associated with altered immune function in humans, including autoimmune disease and impaired response to vaccination. However, changes to the profile of inflammatory biomarkers in adults exposed to PFASs has not been extensively described. Objective: To estimate cross-sectional associations between serum PFASs and markers of inflammation among adults in a population exposed to aqueous film forming foam (AFFF)-contaminated drinking water. Methods: We quantified concentrations of 48 PFASs in non-fasting serum samples from 212 non-smoking adults. In the same serum samples, we measured concentrations of ten pro- and anti-inflammatory cytokines. We restricted analysis to seven PFASs detected in >85% of participants and the following four cytokines detected in ≥30% of participants: interleukin [IL]-1β, IL-6, IL-10, and tumor necrosis factor [TNF]-α. We fit multiple linear regression or logistic regression models, adjusted for potential confounders, to estimate associations between concentrations of each PFAS and either continuous or categorical (above vs below limit of detection) concentrations of each cytokine. We additionally applied Bayesian kernel machine regression to describe the combined effect of the PFAS mixture on each cytokine outcome. Results: Certain PFAS concentrations in this sample were elevated compared to a US nationally representative sample; median levels of PFHxS, ΣPFOS and ΣPFOA in this sample were 13.8, 2.1 and 1.7 times higher, respectively, than medians observed in the U.S. sample. Higher concentrations of multiple PFASs were significantly associated with lower odds of detectable IL-1β. Weaker associations were observed with other cytokines. In general, perfluoroalkyl carboxylic acids had inverse associations with TNF-α, whereas the perfluoroalkyl sulfonic acids showed positive associations. Conclusions: We observed preliminary evidence of altered inflammatory profiles among adults with elevated serum concentrations of PFASs due to contaminated drinking water. Modifications to inflammatory pathways may be one mechanism by which PFAS exposures produce adverse health effects in humans, but this finding requires verification in longitudinal studies as well as phenotypic anchoring to immune function outcomes

Steroid-sparing agents in giant cell arteritis

Background: Giant cell arteritis is the commonest form of medium-to-large vessel vasculitis, requiring long-term corticosteroid therapy. The short- and long-term side effects of corticosteroids are many, including weight gain, psychological effects, osteoporosis, cardiometabolic complications, and infections. Materials and Methods: Various agents used in place of or in combination with corticosteroids to reduce corticosteroid-related side effects were reviewed. However, considerable variation in practice was identified giving unclear guidance. This review included the most recent evidence on methotrexate, mycophenolate mofetil, azathioprine, cyclophosphamide, abatacept, and tocilizumab Results and Discussion: Also discussed are encouraging results with tocilizumab in GCA patients. Amongst the agents available for steroid-sparing effects, tocilizumab demonstrated the most robust data and is consequently recommended as the agent of choice for steroid-sparing, for remission induction, remission maintenance, and treating relapsing and refractory cases of GCA.Published versio

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

On the Irreducible Representations of the Specializations of the Generic Hecke Algebra of Type F4

AbstractA complete determination of the irreducible modules of specialized Hecke algebras of type F4, with respect to specializations with equal parameters, was obtained by M. Geck and K. Lux (1991, Manuscripta Math.70, 285–306). A similar determination for specializations with v=u2 and v=u4 was obtained by K. Bremke (1994, Manuscripta Math.83, 331–346). In this paper, we determine the irreducible modules for all remaining specializations other than those into fields of characteristic 2 or 3, obtaining en route decompositions of the generic irreducible modules under such specializations. We find that the decomposition matrices may be expressed in lower uni-triangular form in all these cases

On root subsystems and involutions in Sn

Given an involution z in W, where W is the symmetric group of degree n, we study the relation between the subsystems of a root system for W corresponding to certain decreasing subsequences of z and the two-sided Kazhdan-Lusztig cell of W containing z. © Glasgow Mathematical Journal Trust 2010