Association of Combined Exposure to Ambient Air Pollutants, Genetic Risk, and Incident Rheumatoid Arthritis: A Prospective Cohort Study in the UK Biobank.

BACKGROUND: Evidence for a potential link between air pollution and rheumatoid arthritis (RA) is inconsistent, and the modified effect of genetic susceptibility on the relationship between air pollution and RA has not been well studied. OBJECTIVE: Using a general population cohort from the UK Biobank, this study aimed to investigate the associations between various air pollutants and the risk of incident RA and to further estimate the impact of combined exposure to ambient air pollutants on the risk of developing RA under the modification effect of genetic predisposition. METHODS: A total of 342,973 participants with completed genotyping data and who were free of RA at baseline were included in the study. An air pollution score was constructed by summing the concentrations of each pollutant weighted by the regression coefficients with RA from single-pollutant models to assess the combined effect of air pollutants, including particulate matter (PM) with diameters ≤2.5µm (PM2.5), between 2.5 and 10µm (PM2.5-10), and ≤10µm (PM10), as well as nitrogen dioxide (NO2) and nitrogen oxides (NOx). In addition, the polygenic risk score (PRS) of RA was calculated to characterize individual genetic risk. The Cox proportional hazard model was used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) of associations of single air pollutant, air pollution score, or PRS with incident RA. RESULTS: During a median follow-up time of 8.1 y, 2,034 incident events of RA were recorded. The HRs (95% CIs) of incident RA per interquartile range increment in PM2.5, PM2.5-10, PM10, NO2, and NOx were 1.07 (1.01, 1.13), 1.00 (0.96, 1.04), 1.01 (0.96, 1.07), 1.03 (0.98, 1.09), and 1.07 (1.02, 1.12), respectively. We also found a positive exposure-response relationship between air pollution score and RA risk (pTrend=0.000053). The HR (95% CI) of incident RA was 1.14 (1.00, 1.29) in the highest quartile group compared with the lowest quartile group of the air pollution score. Furthermore, the results of the combined effect of air pollution score and PRS on the RA risk showed that the risk of RA incidence in the highest genetic risk and air pollution score group was almost twice that of the lowest genetic risk and air pollution score group [incidence rate (IR) per 100,000 person-years: 98.46 vs. 51.19, and HR= 1.73 (95% CI: 1.39, 2.17) vs. 1 (reference)], although no statistically significant interaction between the air pollution and genetic risk for incident RA was found (pInteraction>0.05). DISCUSSION: The results revealed that long-term combined exposure to ambient air pollutants might increase the risk of RA, particularly in those with high genetic risk. https://doi.org/10.1289/EHP10710.

Short-term effect of ambient temperature and ambient temperature changes on the risk of warts outpatient visits in Hefei, China: a retrospective time-series study.

Concerns are growing about the adverse health effects of ambient temperature and ambient temperature changes. However, the association between ambient temperature and ambient temperature changes on the risk of warts outpatient visits is poorly understood. Our study used the distributed lag non-linear model (DLNM) aimed to evaluate the association between ambient temperature, ambient temperature changes (including temperature change between neighboring days (TCN) and diurnal temperature range (DTR)), and warts outpatient visits. We also performed subgroup analyses in order to find susceptible populations by gender and age groups. The maximum relative risk (RR) of low ambient temperature (0 °C) for warts outpatient visits was 1.117 (95% CI: 1.041-1.198, lag 04 days), and the maximum RR of high ambient temperature (32 °C) for warts outpatient visits was 1.318 (95% CI: 1.083-1.605, lag 07 days). The large temperature drop (TCN = - 3 °C) decreased the risk of warts visits, with the lowest RR value at the cumulative exposure of lag 7 days (RR = 0.888, 95% CI: 0.822-0.959), and the large temperature rise (TCN = 2 °C) increased the risk of warts visits, with the highest RR value at the cumulative exposure of lag 7 days (RR = 1.080, 95% CI: 1.022-1.142). Overall, both low and high ambient temperatures and large temperature rise can increase the risk of warts visits, while large temperature drop is a protective factor for warts visits. However, we did not find any association between DTR and warts visits. Furthermore, subgroup analyses showed that males and the young (0-17 years old) were more sensitive to low and high ambient temperatures, and the elderly (≥ 65 years old) were more susceptible to TCN. The results may provide valuable evidence for reducing the disease burden of warts in the future.

Simultaneous determination of molecular weights and contents of water-soluble polysaccharides and their fractions from Lycium barbarum collected in China.

Molecular weights and contents of water-soluble polysaccharides and their fractions in fifty batches of fruits of Lycium barbarum (wolfberry) collected from different regions of China, including Qinghai, Ningxia, Inner Mongolia, Xinjiang, and Gansu, were simultaneously determined using high performance size exclusion chromatography (HPSEC) coupled with multi angle laser light scattering (MALLS) and refractive index detector (RID) with the refractive index increment (dn/dc). Results showed that HPSEC chromatograms and molecular weight distributions of polysaccharides in L. barbarum collected from different regions of China were similar. Furthermore, the average contents of each polysaccharide fraction (peaks 1, 2, and 3) in crude polysaccharides of L. barbarum collected from Ningxia were similar with those of Inner Mongolia, Xinjiang, and Gansu, respectively. However, significant difference was found between polysaccharides in L. barbarum collected from Ningxia and Qinghai. Moreover, the average amounts of total polysaccharide fractions (peaks 1, 2, and 3) in the raw material of L. barbarum collected from Ningxia were significantly higher than that of Qinghai. These results may contribute to the rational usage of L. barbarum produced in China, and are beneficial for the improvement of their quality control. Results suggested that HPSEC-MALLS-RID with the dn/dc method could be used as a routine method for the quality evaluation of polysaccharides from natural resources and their products.

Characterization and comparison of polysaccharides from Lycium barbarum in China using saccharide mapping based on PACE and HPTLC.

Water-soluble polysaccharides from 51 batches of fruits of L. barbarum (wolfberry) in China were investigated and compared using saccharide mapping, partial acid hydrolysis, single and composite enzymatic digestion, followed by polysaccharide analysis by using carbohydrate gel electrophoresis (PACE) analysis and high performance thin layer chromatography (HPTLC) analysis, respectively. Results showed that multiple PACE and HPTLC fingerprints of partial acid and enzymatic hydrolysates of polysaccharides from L. barbarum in China were similar, respectively. In addition, results indicated that ß-1,3-glucosidic, α-1,4-galactosiduronic and α-1,5-arabinosidic linkages existed in polysaccharides from L. barbarum collected in China, and the similarity of polysaccharides in L. barbarum collected from different regions of China was pretty high, which are helpful for the improvement of the performance of polysaccharides from L. barbarum in functional/health foods area. Furthermore, polysaccharides from Panax notoginseng, Angelica sinensis, and Astragalus membranaceus var. mongholicus were successfully distinguished from those of L. barbarum based on their PACE fingerprints. These results were beneficial to improve the quality control of polysaccharides from L. barabrum and their products, which suggested that saccharide mapping based on PACE and HPTLC analysis could be a routine approach for quality control of polysaccharides.

In vitro proliferation and differentiation of adipose-derived stem cells isolated using anti-CD105 magnetic beads.

The present study aimed to investigate the feasibility of isolating adipose-derived stem cells (ADSCs) by selecting cells that express the surface receptor CD105. Surface antigen expression of the unsorted cells was undertaken using FACS analysis. Primary adipose-derived cells were isolated. The second passage cells were incubated with anti-CD105 magnetic beads, and separated using a magnetic separator. Cell growth and colony formation was determined by counting and Giemsa staining, respectively. Cells also underwent histological immunohistochemical, and RT-PCR analyses to determine their chondrogenic, adipogenic and osteogenic potential. Increased cell proliferation and colony formation was observed in CD105-positive (CD105⁺) as compared to the CD105-negative (CD105⁻) cells (P<0.001). Following induction, the expression of type II collagen and the number of calcium deposits and lipid droplets in the CD105⁺ ADCs were markedly higher than in the CD105⁻ ADCs. Furthermore, increased alkaline phosphatase (AKP), leptin and PPARγ2 mRNA expression was detected in the CD105⁺ ADCs (P<0.01). Isolation of CD105⁺ ADSCs by MACS was feasible. Thus, CD105 can be used as a relatively specific marker for the selection of ADSCs. Although the chondrogenic, adipogenic and osteogenic potential of these cells is suggestive of their potential for use in tissue engineering treatments, further in vivo studies are necessary.

[The effect of pcDNA 3.1/RPs15 on skin fibroblasts in vitro].

OBJECTIVE: To construct eukaryotic expression vector of ribosomal protein sl5(RPs15) gene and study its effect on mouse skin fibroblasts in vitro. METHODS: The RPs15 cDNA encoding region of fetal mouse skin was amplified by reverse transcription-polymerase chain reaction (RT-PCR) method and cloned into eukaryotic expression vector pcDNA3.1(-). The recombinant plasmid was transfected into adult mouse skin fibroblasts by FuGENE6 transfection reagents. Then the expression of RPs15 gene, was detected and its biological effect on fibroblasts was measured. RESULTS: The DNA sequencing result of pcDNA3.1/RPs15 was identical with the reported. The RPs15 gene was expressed in transfected fibroblasts. The growth density of fibroblasts decreased with the conformation changing accordingly. CONCLUSIONS: The eukaryotic expression vector pcDNA3.1/RPs15 is successively constructed and can be expressed in mouse skin fibroblasts. The results set up a basis for further study of the effect of RPs15 gene on skin fibroblasts.