Acute and subacute inhalation toxicity assessment of WS-23 in Sprague-Dawley rats.

2-isopropyl-N,2,3-trimethylbutyramide (WS-23) is a well-known artificial synthesis cooling agent widely used in foods, medicines, and tobaccos. As a commonly cooling agent in e-cigarette liquids, WS-23 has led to concerns about the inhalation toxicity with the prosperous of e-cigarettes in recent years. Thus, the aim of this study is to assess the acute and subacute inhalation toxicity of WS-23 in Sprague-Dawley (SD) rats according to the Organization for Economic Cooperation and Development (OECD) guidelines. In the acute toxicity study, there was no mortality and behavioral signs of toxicity at the limit test dose level (340.0 mg/m3 ) in the exposure period and the following 14-day observation period. In the subacute inhalation toxicity study, there was no significant difference observed in the body weights, feed consumption, and relative organ weights. Haematological, serum biochemical, urine, and bronchoalveolar lavage fluid (BALF) analysis revealed the non-adverse effects after 28-day repeated WS-23 inhalation (342.85 mg/m3 ), accompanied by slight changes in few parameters which returned to normal during the 28-day recovery period. The histopathologic examination also did not show any differences in vital organs. In conclusion, the maximum tolerated dose for WS-23 acute inhalation is not less than 340.0 mg/m3 , and the No Observed Adverse Effect Level (NOAEL) of WS-23 subacute inhalation was determined to be over 342.85 mg/m3 .

Common Variant in TREM1 Influencing Brain Amyloid Deposition in Mild Cognitive Impairment and Alzheimer's Disease.

Triggering receptor expressed on myeloid cells-1 (TREM1) has been reported to associate with Alzheimer's disease (AD) pathology. Recently, TREM1 variant rs2234246A was reported to regulate TREM-1 protein and mRNA levels. We explored the effect of rs2234246 on AD specific biomarker (amyloid-ß PET) to look into the role of this TREM1 locus in AD pathogenesis. We calculated the association of the TREM1 locus with amyloid deposition at baseline and follow-up using both multiple linear models and mixed effect models respectively in 522 the Alzheimer's Disease Neuroimaging Initiative (ADNI) subjects. We also analyzed the association of TREM1 with this marker in subregions during the AD process. In the pooled sample, TREM1 rs2234246A was associated with the levels of mean standard uptake volume ratios (SUVRs) at baseline (p = 0.02) and the length of follow-up (p = 0.04) in the cross-sectional analysis and longitudinal study. Subgroup analyses showed no correlation between rs2234246A and amyloid deposition in the cognitively normal (CN) group. In the mild cognitive impairment (MCI) group, TREM1 rs2234246A reached significance at baseline (p = 0.04) and the length of follow-up (p = 0.04). In the AD group, TREM1 rs2234246A was associated with mean SUVR at baseline (p < 0.001) and the length of follow-up (p = 0.001). In subregion analyses, TREM1 rs2234246A was detected to be related to Aß deposition. This study demonstrated an association between TREM1 variant rs2234246 and brain amyloidosis. Our findings implied that this variant is involved in AD by influencing Aß neuropathology.