Estimations of body fat by anthropometry or bioelectrical impedance differ from those by dual-energy X-ray absorptiometry in prefrail community-dwelling older women.

This study aimed to compare different methods to assess body fat (BF). We hypothesized that bioelectrical impedance analysis (BIA) or anthropometry may be used to estimate BF in prefrail older women, equivalently to dual-energy X-ray absorptiometry (DXA). The cross-sectional study included 72 prefrail community-dwelling older women (71.13 ± 4.65 years old; body mass index [BMI] 28.89 ± 4.23 kg/m2). The BF percentage (%BF) was estimated using anthropometry with the Durnin & Womersley (D&W) and Petroski's predictive equations, BIA with 2 Baumgartner predictive equations (BIA 1 and BIA 2), and DXA. All methods differed significantly from DXA according to assessments using repeated measures ANOVA and pairwise comparisons. The mean %BF varied between 39.99 ± 3.42% (D&W) and 43.93 ±â€¯5.06% (DXA). Multiple regression analysis with age and BMI as covariates showed positive correlations (R2 = 0.91) in models with D&W equation and BMI, and with BIA 2 and BMI; however, BMI explained more of the model (71%) than the equations. Furthermore, Bland-Altman test revealed a proportional bias for D&W and for BIA 2, with underestimation of BF varying across different %BF values. Petroski's skinfold equation showed a positive correlation on linear regression (R2 = 0.74) and no proportional bias; however, Bland-Altman analysis revealed high limits of agreement (-13.6 to -0.05), thus compromising clinical application. To conclude, compared with DXA, all the equations tested showed a high disagreement and wide limits of agreement, restricting their use in clinical practice to estimate the BF in prefrail older women.

A 3'UTR polymorphism marks differential KLRG1 mRNA levels through disruption of a miR-584-5p binding site and associates with pemphigus foliaceus susceptibility.

Genetic variations mapping to 3' untranslated regions (3'UTRs) may overlap with microRNA (miRNA) binding sites, therefore potentially interfering with translation inhibition or messenger RNA (mRNA) degradation. The aim of this study was to investigate whether single nucleotide polymorphisms (SNPs) located within the 3'UTRs of six candidate genes and predicted to interfere with miRNA ligation could account for disease-relevant differential mRNA levels. Focusing on pemphigus foliaceus (PF) - an autoimmune blistering skin condition with unique endemic patterns - we investigated whether nine 3'UTR SNPs from the CD1D, CTLA4, KLRD1, KLRG1, NKG7, and TNFSF13B genes differentially expressed in PF were disease-associated. The heterozygous genotype of the KLRG1 rs1805672 polymorphism was associated with increased predisposition to PF (A/G vs. A/A: P=0.038; OR=1.60), and a trend for augmented susceptibility was observed for carriers of the G allele (P=0.094; OR=1.44). In silico analyses suggested that rs1805672 G allele could disrupt binding of miR-584-5p, and indicated rs1805672 as an expression Quantitative Trait Locus (eQTL), with an effect on KLRG1 gene expression. Dual-luciferase assay showed that miR-584-5p mediated approximately 50% downregulation of the reporter gene's activity through the 3'UTR of KLRG1 harboring rs1805672 A allele (vs. miRNA-negative condition, P=0.006). This silencing relationship was lost after site-directed mutation to G allele (vs. miRNA-negative condition, P=0.391; vs. rs1805672 A allele, P=0.005). Collectively, these results suggest that a disease-associated SNP located within the 3'UTR of KLRG1 directly interferes with miR-584-5p binding, allowing for KLRG1 mRNA differential accumulation, which in turn may contribute to pathogenesis of autoimmune diseases, such as pemphigus.

Anti-Desmoglein 1 and 3 Autoantibody Levels in Endemic Pemphigus Foliaceus and Pemphigus Vulgaris from Brazil.

BACKGROUND: Pemphigus is a group of autoimmune blistering diseases of which the major forms are pemphigus foliaceus (PF) and vulgaris (PV). In Brazil, PF occurs in an endemic form also known as fogo selvagem. The main autoantibody in PF is against desmoglein 1 (DSG1), while in PV the main antibody is anti-desmoglein 3 (DSG3), but often anti-DSG1 is also present. The aim of the present study was to analyze the levels of anti-DSG1 and antiDSG3 autoantibodies in Brazilian PF and PV patients, considering different stages of the disease for PF patients and comparing these levels to those of healthy individuals living in and outside the endemic regions. METHODS: Levels of anti-DSG1 and anti-DSG3 were measured in the sera of Brazilian PF (n = 68) and PV (n = 20) patients as well as in clinically healthy (control) individuals (n = 48) by Enzyme Linked Immunosorbent Assay (ELISA). Comparisons were made using Kruskal-Wallis and Mann-Whitney tests. RESULTS: As expected, anti-DSG1 was more prevalent among PF patients (84% against 43% in PV), while antiDSG3 was more prevalent in PV patients (50% against 4% in PF). Levels of anti-DSG1 in PF patients in remission differed from those in patients undergoing active disease (p = 0.003), and patients in long-term remission (more than two years without presenting new lesions) were similar to control individuals living in the endemic region and surrounding area (p = 0.09). Moreover, patients with a more severe form of the disease had higher levels of anti-DSG1 (at least 134 U/mL, mean of 233 U/mL) than patients with a less severe form (fewer lesions) (mean of 193 U/mL, including two negative individuals). CONCLUSIONS: Despite the importance of these antibodies for diagnosis and management purposes, their presence in a healthy individual and in patients under remission indicates that caution should be taken when using anti-DSG for diagnosis, especially in endemic areas.