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Objective: To improve the extraction rate and product purity of Chinese soft-shelled turtle （pelodiscussinensis）dorsal collagen. Methods: The decalcification rate and collagen recovery rate were used as evaluation indicators to investigate the effects of hydrochloric acid concentration, decalcification time, decalcification temperature and solid-liquid ratio on the decalcification of the carapace of Chinese soft-shelled turtle. The removal process of calcium salts was optimized, and the structural changes of decalcified and non-decalcified turtle carapace collagen were analyzed by SDS-PAGE, ultraviolet absorption spectroscopy, infrared absorption spectroscopy, amino acid analysis and other techniques under the same extraction conditions. Results: The optimal decalcification process conditions were hydrochloric acid concentration of 0.8 mol/L, decalcification time of 2 h, decalcification temperature of 28 ℃, and solid-liquid ratio of 1∶25 （g/mL）. Under these conditions, the decalcification rate and collagen recovery rate were （67.35±0.92）% and （90.77±1.08）%, respectively. The collagen content and extraction rate per unit mass of soft-shelled turtle carapace were significantly increased （P＜0.05） after decalcification with hydrochloric acid, but the structural characteristics of collagen did not change significantly. Conclusion: Hydrochloric acid has a good decalcification effect on the decalcification of turtle carapace, and has no effect on the structural properties of its collagen.

Background and Aim: Triggering receptor expressed on myeloid cells 2 (TREM2) plays crucial roles in metabolic homeostasis and inflammatory response. Altered metabolic function in macrophages could modulate their activation and immune phenotype. The present study aimed to investigate the expression of TREM2 in non‐alcoholic fatty liver disease (NAFLD) and to clarify the underlying mechanism of TREM2 on macrophages lipid metabolism and oxidative stress. Methods: Hepatic TREM2 expression and its relationship with NAFLD progression were analyzed in patients with NAFLD and mice fed a high‐fat diet. Lipid metabolism and oxidative stress were investigated in macrophages from NAFLD mice or stimulated with saturated fatty acids. Knockdown and overexpression of TREM2 were further explored. Results: Triggering receptor expressed on myeloid cells 2+ macrophages were increased along with NAFLD development, characterized by aggravated steatosis and liver damage in humans and mice. TREM2 expression was upregulated and lipid metabolism was changed in macrophages from NAFLD mice or metabolically activated by saturated fatty acid in vitro, as demonstrated by increased lipid uptake and catabolism, but reduced de novo synthesis of fatty acids (FAs). Regulation of TREM2 expression in lipid‐laden macrophages reprogrammed lipid metabolism, especially the fatty acid oxidation capacity of mitochondria. TREM2 knockdown promoted oxidative stress by aggravating FAs deposition in mitochondria. Intervention of mitochondrial FAs transport in lipid‐laden macrophages alleviated FA deposition and reactive oxygen species production induced by TREM2 knockdown. Conclusions: Triggering receptor expressed on myeloid cells 2 expression was associated with the lipid metabolic profile and reactive oxygen species production in macrophages. High expression of TREM2 in macrophages may protect the liver from oxidative stress in NAFLD. [ABSTRACT FROM AUTHOR]

In this study, the stress–cycle number (S–N curve) of a composite consisting of ceria‐stabilized zirconia (Ce‐TZP) and alumina (Al2O3) was measured. First, the initial bending strength of the Ce‐TZP/Al2O3 composite was determined using a four‐point bending technique. Next, stress above 70% of the initial bending strength was applied on the composite for up to 1,000,000 cycles. Transformation bands were formed on the tensile surface in the first several cycles as the stress was higher than a critical value. The number and width of bands then changed marginally after their fomraiton. Fatigue failure occured at the band with the largest width, as a result of slow crack growth process. The transformation bands could be removed using a post‐fatigue heating treatment. After removal of these bands, the strength was consequently enhanced. [ABSTRACT FROM AUTHOR]

Objectives: To describe four endoscopic endonasal subapproaches, namely, the trans‐lamina papyracea, trans‐prelacrimal recess, trans‐Meckel's cave, and transclival approaches for trigeminal schwannomas (TSs). Methods: This retrospective study reviewed the medical records and intraoperative videos of 38 patients with TSs who underwent endoscopic endonasal approach (EEA) between Jan 2013 and Dec 2021. Results: According to Jeong's classification, for TS equally in middle and posterior fossae (MP), a purely trans‐Meckel's cave approach was carried out in 2 cases, and a combined transclival approach was carried out in 4 cases. The four tumors that involved infratemporal fossa (two E3, one mE3, and one Mpe3) were performed via a trans‐prelacrimal recess approach, and type Mpe3 was also assisted by the trans‐Meckel's cave approach. One patient with type E1 was treated with a trans‐lamina papyracea approach. The other 27 cases, including type M, Mp, ME2, and MpE2, were all removed by a purely trans‐Meckel's cave approach. Thirty‐six patients (97.4%) received total resection under a purely EEA. The functional abilities and preoperative symptoms of 31 patients (88.6%) improved. Eight (21.1%) patients experienced permanent neurological function deficits. Postoperative cerebrospinal fluid and intraoperative internal carotid artery injury occurred in 1 (2.6%) patient. Conclusion: According to the specific endoscopic endonasal subapproaches corresponding to the different TS locations, satisfactory results can be obtained for most types of tumors. It represents an effective alternative to the open transcranial approach and can also be properly used in most types of TS with experienced hands. Level of Evidence: 4 Laryngoscope, 133:2564–2571, 2023 [ABSTRACT FROM AUTHOR]