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Background: polyunsaturated fatty acids (PUFAs) are a category of fatty acids that contain omega-3 and omega-6 fatty acids, which constitute a substantial portion of the Western diet and are vital for maintaining human wellness. The extent to which circulating PUFAs influence the effects of BMI on leukocyte telomere length (LTL) is unknown. Additionally, the impact of circulating PUFA on LTL remains controversial in observational studies. Methods: Using publicly accessible datasets, a genome-wide association study (GWAS) was carried out to determine genetic association estimates for BMI, circulating PUFAs, and LTL. The circulating PUFAs considered were omega-3 PUFAs (i.e., docosahexaenoic acid (DHA) and total omega-3 PUFAs) and omega-6 PUFAs (i.e., linoleic acid (LA) and total omega-6 PUFAs). Two-sample Mendelian randomization (MR) was used to investigate the causal relationships between BMI and PUFA with LTL. Additionally, we examined whether certain PUFA mediate the impact of BMI on LTL. Results: None of the evidence supported a causal effect of genetically predicted DHA and total omega-3 PUFA on LTL (DHA: β = 0.001, 95% CI: −0.023 to 0.026, p = 0.926; total omega-3 PUFA: β = 0.008, 95% CI: −0.013 to 0.029, p = 0.466). After conducting sensitivity analyses to account for various models of horizontal pleiotropy, the causal association between higher levels of LA and longer LTL persisted (β = 0.034, 95% CI 0.016 to 0.052, p < 0.001). Adjusting for LA in genetics reduced the effect of BMI on LTL from β = -0.039 (95% CI: -0.058 to -0.020, p < 0.001) to -0.034 (95% CI: -0.054 to -0.014, p < 0.001). Conclusions: This MR study indicates that an increase in genetically predicted circulating LA levels is associated with longer LTL. Additionally, it appears that circulating LA levels play a role in mediating some of the impact that BMI has on LTL. [ABSTRACT FROM AUTHOR]

Background: Type 2 diabetes mellitus (T2DM) may affect the oral microbial community, exacerbating periodontal inflammation; however, its pathogenic mechanisms remain unclear. As nucleotide‐binding oligomerization domain 2 (NOD2) plays a crucial role in the activation during periodontitis (PD), it is hypothesized that changes in the oral microbial community due to diabetes enhance periodontal inflammation through the activation of NOD2. Methods: We collected subgingival plaque from 180 subjects who were categorized into two groups based on the presence or absence of T2DM. The composition of oral microbiota was detected by 16S rRNA high‐throughput sequencing. In animal models of PD with or without T2DM, we assessed alveolar bone resorption by micro‐computerized tomography and used immunohistochemistry to detect NOD2 expression in alveolar bone. Primary osteoblasts were cultured in osteogenic induction medium with high or normal glucose and treated with inactivated bacteria. After 24 h of inactivated bacteria intervention, the osteogenic differentiation ability was detected by alkaline phosphatase (ALP) staining, and the expressions of NOD2 and interleukin‐12 (IL‐6) were detected by western blot. Results: The relative abundance of Parvimonas and Filifactor in the T2DM group was increased compared to the group without T2DM. In animal models, alveolar bone mass was decreased in PD, particularly in T2DM with PD (DMPD) group, compared to controls. Immunohistochemistry revealed NOD2 in osteoblasts from the alveolar bone in both the PD group and DMPD group, especially in the DMPD group. In vitro, intervention with inactivated Parvimonas significantly reduced ALP secretion of primary osteoblasts in high glucose medium, accompanied by increased expression of NOD2 and IL‐6. Conclusions: The results suggest that T2DM leading to PD may be associated with the activation of NOD2 by Parvimonas. [ABSTRACT FROM AUTHOR]

Although Stewart platforms have been applied in the design of aircraft and vehicle simulators and parallel robots for many years, the closed-form solution of direct (forward) position analysis of Stewart platforms has not been completely solved. Up to the present time, only the relatively simple Stewart platforms have been analyzed. Examples are the octahedral, the 3-6 and the 4-4 Stewart platforms, of which the forward position solutions were derived as an eighth or a twelfth degree polynomials with one variable in the form of square of a tan-half-angle. This paper further extends the direct position analysis to a more general case of the Stewart platform, the 4-6 Stewart platforms, in which two pairs of the upper joint centers of adjacent limbs are coincident. The result is a sixteenth degree polynomial in the square of a tan-half-angle, which indicates that a maximum of 32 configurations may be obtained. It is also shown that the previously derived solutions of the 3-6 and 4-4 Stewart platforms can be easily deduced from the sixteenth degree polynomial by setting some geometric parameters be equal to 1 or 0.

The marine foodborne enteropathogen Vibrio parahaemolyticus contains the chief organic peroxide reductases AphC1-AhpC2 and a putative organic hydroperoxide resistance enzyme (Ohr; VPA1681) against different peroxides. This study investigated the function of the Ohr under the presence of AhpC1-AhpC2 in this pathogen by gene mutation. Experimental results demonstrated that the ohr gene product was a weak scavenger of H 2 O 2 only in the mutant strains that lacked the peroxide sensor/regulator oxyR and ahpC1 - ahpC2 genes. The Ohr of V. parahaemolyticus was highly effective at scavenging organic peroxide, as demonstrated by assaying the defective changes in the Δ ohr mutant strain and determining the detoxifying activity of the purified recombinant V. parahaemolyticus Ohr vp protein in the reduced form. The Ohr and AhpC1-AhpC2 exhibited similar functions against organic peroxides; however, only the ΔahpC1ΔahpC2 mutant strain showed a significant increase in susceptibility to several disinfectants, organic acids, and antibiotics compared with the wild-type strain. The transcription of the ohr gene depended on exogenous cumene hydroperoxide (cumene) stress and was markedly enhanced in the ΔohrR (VPA1682) mutant strains. This study revealed the organic hydroperoxide reductase activity of the Ohr in V. parahaemolyticus, and its role probably depends on sophisticated regulation by OhrR. IMPORTANCE Vibrio parahaemolyticus is the most prevalent foodborne pathogen in Taiwan and some other coastal Asian countries, and its antioxidative activity contributes to the tolerance of this bacterium to different environmental stresses. This study reports on the function of the organic hydroperoxide resistance gene ( ohr ; VPA1681) and its gene regulator, ohrR (VPA1682), in this pathogen. The strain with the ohr gene had effective protection against organic peroxide, and the recombinant Ohr vp was active in its reduced form. The function of Ohr was significant mostly in strains in which the function of AhpC1-AhpC2 was limited. The ohrR repressor of the ohr gene was effective at low concentrations of organic peroxide. Other common Vibrio species that contain homologous ohr , ohrR , ahpC1 , and ahpC2 genes, which are phylogenetically close to those of V. parahaemolyticus, may share similar functions to those revealed in this study.