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The Altyn Tagh Fault (ATF) serves as a key continental‐scale controlling structural element of the Tibetan Plateau. However, its eastward extent remains controversial. Here we use high‐resolution seismic reflection profiles to investigate the subsurface structures of the easternmost ATF and use these to delimit the easternmost extent of the fault. The structural analyses show an eastward geometric change from transpressional positive flower structures to compressional thrusts, with transpression‐induced shortening magnitudes decreasing eastwards from a maximum of ~5.3 km to being absent. Stratigraphic controls indicate that the deformation took place over the last ~<1.2 Ma. Our wider findings lead us to: (a) reject the suggestion that the ATF previously extended beyond the Kuantan Shan‐Hei Shan to link with the Alxa‐East Mongolia Fault; and (b) propose that the rigid block model used to describe the Tibetan Plateau crust is not consistent with the extent and structural details of the easternmost ATF. [ABSTRACT FROM AUTHOR]

Objective To introduce a modified model for quantitative testing of glucose microleakage by constant air pressure and evaluate the sealing ability of four root canal sealers including AH Plus, Roeko Seal, Cortisomol and RC Sealer. Methods Fifty-six straight maxillary anterior teeth were randomly divided into four experimental groups with 12 samples in each group, group A: AH Plus, group B: Roeko Seal, group C: Cortisomol, group D: RC Sealer, and positive and negative control group with 4 samples in each. After regular root preparation, samples in experimental groups were obturated by cold gutta-percha lateral compaction technique with sealers according to group description. Control groups were obturated with cold gutta-percha only. Through the model above, the value of glucose microleakage from crown to root was measured at 1, 3, 5, 7, 10, 15, 20, 25, 30 days with the glucose oxidase-peroxidase method (GOD-POD). Results At day 1, 3, 5, no significant difference of microleakage was found between group A and B (GOD-POD). The same result was also seen between group C and D. From 7 days, microleakage value in each experimental group gradually increased, and statistical difference was found between groups (P<0.05). Conclusion This new model using constant air pressure is easy to establish, sensitive and practical. Among all the sealers evaluated, polydimethylsiloxane based root canal sealer, Roeko Seal has the greatest sealing ability, while epoxy-amine resin based AH Plus is second and Zinc Oxide based Cortisomol and RC Sealer have the least sealing ability. [ABSTRACT FROM AUTHOR]

Defining the northern margin of the Tibetan Plateau, the Altyn Tagh Fault system (ATFs)exerts a crucial role in accommodating intracontinental deformation during the India-Asiaconvergence. The North Altyn fault (NAF), demarcating the western boundary of the ATFs inthe Altun Shan region, was testified to exist a structural shift from sinistral along-strikeslipping to thrusting during the Cenozoic era. However, the exact timing of the shift remainsan issue to be refined. In this study, we conducted LA-ICP-MS based apatite fission trackdating at massifs of both the hanging wall and footwall along the NAF, to shed light on datingthe thrusting-related exhumation of the NAF. The results show that the hanging wall massifsof the NAF present a quasi-isothermal quiescence during the early Cenozoic, followedby a rapid cooling phase with mean cooling rate of 6.66 ± 0.72 ˚ C / Ma since∼15 Ma, resulting from accelerated exhumation which has been interpreted tomark intense vertical uplift of the NAF. Significantly younger age (∼5 Ma) buthigher rate (15.33 ± 2.10 ˚ C / Ma) of rapid-cooling event occurred at the footwallcompared to the hanging wall suggests a northward propagation of thrusting into theinterior Tarim basin. Combining previous studies, we attribute the structural shift ofthe NAF from along-strike slipping to thrusting to the Mid-Miocene kinematicreorganization of the ATFs, supporting to the two-stage evolution model of theAFTs that: (1) during ∼50-15 Ma, the NAF acted as a part of the Altyn Tagh faultexperiencing along-strike slipping, with the Altun Shan elevated north within bigrestraining-double-bends; and (2) after ∼15 Ma, the Altyn Tagh fault cut through thedouble-bends with significant thrusting along the NAF, circumscribing the presenttriangle-shaped Altun Shan featured with uplifting south beginning at ∼15 Ma. [ABSTRACT FROM AUTHOR]

Ubiquitin-specific protease 31 (USP31) is a member of deubiquitinase family that is involved in nuclear factor-κB activation and sarcomagenesis. However, little is known about posttranslational modification in the regulation of its activity and cervical cancer cell growth. In our study, we found that the Lys1264 residue of USP31 can be modified with an acetyl group by high-resolution mass spectrometry in HeLa cell line, and site-specific mutagenesis can significantly increase USP31 ubiquitin hydrolase activity and decrease the expression of p65. When being transfected with a plasmid expressing mutated USP31, the number of cancer cells was significantly decreased. We also observed that mutated USP31 could promote apoptosis but not cell cycle by flow cytometer analysis. Overexpression of mutated USP31 could reverse the effect in USP31 knockdown cell line. To further investigate its activity in tumorigenesis, deacetylase sirtuin 1 (Sirt1) was shown to interact with USP31 by co-immunoprecipitation and blocking the function of Sirt1 by knockdown or the inhibitor nicotinamide could increase the acetylation of USP31. When Lys1264 of USP31 mutated, Sirt1 could not remove its acetylation and alter the expression level of p65. Finally, inhibition or knockdown of Sirt1 suppressed USP31 activity in HeLa cell line, leading to cisplatin-induced apoptosis resistance. Therefore, acetylation at Lys1264 suppresses USP31 activity and plays a protective role in cancer cell growth. Our study contributes to understanding the mechanism of USP31 activity regulation and its role in tumorigenesis., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)