Causal Relationships Between Social Isolation and Osteoarthritis: A Mendelian Randomization Study in European Population.

OBJECTIVE: We aimed to investigate the causal relationships between social isolation and osteoarthritis. METHODS: Publicly available genome-wide association study (GWAS) summary statistics of social isolation and osteoarthritis in European population were obtained from the Neale lab Consortium and the Medical Research Council-Integrative Epidemiology Unit (MRC-IEU) consortium, respectively. Single nucleotide polymorphisms (SNPs) associated with the traits were identified by P < 5×10-8 and linkage disequilibrium r2 < 0.1. Three Mendelian randomization (MR) methods including the inverse-variance weighted (IVW) method, weighted median estimator, and MR-Egger regression were used to assess the potential causal effect of social isolation on osteoarthritis and the potential causal effect of osteoarthritis on social isolation. Leave-one-out analysis and test of directional horizontal pleiotropy via MR-Egger regression were performed as sensitivity analyses. RESULTS: When evaluating the causal effect of social isolation on osteoarthritis, five SNPs (rs12364432, rs13291079, rs2352075, rs4958586, rs599550) significantly associated with social isolation were studied as instruments, and social isolation was found to be causally associated with increased risk of osteoarthritis (odds ratio [OR] 1.197 (95% confidence interval (CI) 1.096-1.308) estimated by the IVW method). When evaluating the causal effect of osteoarthritis on social isolation, six SNPs (rs10405617, rs12133235, rs13107325, rs2290573, rs3771501, rs75621460) significantly associated with osteoarthritis were studied as instruments but no causal effect of osteoarthritis on social isolation was found (OR 1.104 (95% CI 0.887-1.375) estimated by the IVW method). Consistent causal relationships were observed when estimated by the weighted median estimator and MR-Egger regression. Leave-one-out analysis and test of directional horizontal pleiotropy suggested the robustness of the above findings. CONCLUSION: Social isolation is causally associated with osteoarthritis, and further work is needed to investigate the potential mechanisms.

The Causal Relationship Between Body Mass Index and the Risk of Osteoarthritis.

OBJECTIVE: The study aimed to explore the causal effect of body mass index (BMI) on osteoarthritis. METHODS: The genome-wide association data of BMI and osteoarthritis were obtained via the Mendelian randomization (MR)-base platform. Single nucleotide polymorphisms (SNPs) significantly associated with BMI were identified and used as instrumental variables, and the causal relationship between BMI and osteoarthritis was examined using the two-sample MR research method. Three statistical methods including inverse-variance weighted (IVW) method, weighted median estimator, and MR-Egger regression were employed. RESULTS: A total of 79 SNPs significantly associated with BMI were identified in the study (P<5×10-8; linkage disequilibrium r2 <0.1). Consistent association between BMI and osteoarthritis was observed when evaluated by different methods (IVW: odds ratio (OR) 1.028, 95% confidence interval (CI) 1.021-1.036; weighted median estimator: OR 1.028, 95% CI 1.019-1.037; MR-Egger regression: OR 1.028, 95% CI 1.009-1.046), which suggests that BMI is positively associated with increased risk of osteoarthritis. There was no evidence that the observed causal effect between BMI and the risk of osteoarthritis was affected by genetic pleiotropy (MR-Egger intercept 1.3×10-5, P=0.959). CONCLUSION: The MR analysis provided the strong evidence to indicate that BMI might be causally associated with the risk of osteoarthritis.

Development of monoclonal antibody for differentiating porcine reproductive and respiratory syndrome virus and identification of a novel non-structural protein 2 epitope peptide.

Porcine reproductive and respiratory syndrome virus (PRRSV) nucleocapsid protein (NP) is the immunodominant region of PRRSV viral proteins. Non-structural protein 2 (Nsp2) and its hypervariable region play an essential role in the differential diagnosis of PRRSV. Western blot and immunofluorescence assay (IFA) analyses found that 2 out of 18 monoclonal antibodies (MAbs) recognized the NP and that 5 of 11 MAbs recognized Nsp2-120aa. IFA data demonstrated that 2 MAbs raised against the NP have a positive reaction to PRRSV; either HP-PRRSV, classic PRRSV or the vaccine strain at 1:100 dilution. Two MAbs raise against Nsp2-120aa also react positively with the classic PRRSV nor HP-PRRSV, but not with the PRRSV vaccine strain TJM-F92. Epitope mapping using truncated proteins identified a novel Nsp2-120aa epitope. In addition, we show that MAb BR/PNsp2-2A20 recognizes a 20 amino acid peptide (707) GRFEFLPKMILETPPPHPCG (727) of Nsp2. Based on our findings, we propose that MAb BR/PNsp2-2A20, raised against Nsp2-120aa of PRRSV, as a candidate specific diagnostic MAb for differentiation of the PRRSV virulent strains infected pig from vaccine strain TJM-F92 inoculated ones. The MAbs developed here have potential for use in diagnostic and research tools, including immunofluorescence assay, enzyme-linked immunosorbent assay and Western blotting.

Aqua-(3-formyl-2-oxidobenzoato-κO,O)(1,10-phenanthroline-κN,N')copper(II) dimethyl-formamide solvate.

In the structure of the title complex, [Cu(C(8)H(4)O(4))(C(12)H(8)N(2))(H(2)O)]·C(3)H(7)NO, the Cu(II) ion is penta-coordinated in a distorted square-pyramidal geometry by two O atoms of a 3-formyl-2-oxidobenzoate dianion and two N atoms of a 1,10-phenanthroline ligand occupying the basal plane and a water O atom located at the apical site. The structure displays O-H⋯O hydrogen bonding and inter-molecular π-π stacking inter-actions between 1,10-phenantroline ligands [inter-planar distance of 3.448 (5) Å].

A binuclear cobalt(II) complex of an NO(3)-donor Schiff base derived from 3-carboxyl-salicylaldehyde and 2-nitro-aniline.

In the crystal structure of the centrosymmetric title complex, bis-{µ-3-[(2-nitro-phen-yl)imino-meth-yl]-2-oxidobenzoato}dicobalt(II), [Co(2)(C(14)H(8)N(2)O(5))(2)], in which the ligand is 3-[(2-nitro-phen-yl)imino-meth-yl]-2-oxidobenzoate, a Schiff base synthesized from 2-nitro-aniline with 3-carboxyl-salicyl-aldehyde, the two cobalt(II) ions in the mol-ecular unit are bridged by two phenolate O atoms of the ligands. Each metal centre has a distorted square-planar geometry. In the crystal structure, mol-ecules are linked by Co⋯O inter-actions involving the nitro O atoms, forming a two-dimensional network. There are also C-H⋯O and π-π stacking inter-actions [centroid-centroid distances of 3.5004 (2), 3.6671 (2) and 3.6677 (2) Å] between adjacent benzene rings of the two-dimensional networks, leading to the formation of a three-dimensional framework.