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The Heihe–Nenjiang–Hegenshan suture zone has long been accepted as the major tectonic boundary between the Xing'an and Songliao blocks and extends through the Great Xing'an Range in NE China, but its location of the northern segment between the Moguqi and Nenjiang areas and its timing remain unclear. We address these issues by presenting zircon LA‐ICP‐MS U–Pb ages, Lu‐Hf isotopes, bulk‐rock major, and trace elemental data for mylonitized rhyolites collected from the Moergenhe Formation in the Nenjiang area and for gabbros of the Moguqi area, respectively. The mylonitized rhyolites, which display an arc‐related geochemical affinity with enrichment in Th and U, and depletion of Nb, Ta, and Ti, and gently right‐tilted rare earth element (REE) patterns (light REE [LREE]/heavy REE [HREE] =4.53–7.60), as well as the εHf (t) values (+6.4 to +11.8) of analyzed zircons, indicate an origin by partial melting of potentially young lower continental crust of a subducting slab. The zircon LA‐ICP‐MS U–Pb data show the formation age of the mylonitized rhyolites is 352.4 Ma. The analyzed gabbros with an emplacement age of 352.6 Ma have high concentrations of Th and U, slightly enriched LREE patterns and relative low LREE/HREE ratios (4.3 to 4.6). These features, together with their high positive εHf (t) values (+7.7 to +15.2), suggest that they were likely derived from the partial melting of a depleted mantle source that was metasomatized by subduction‐related fluids. Combined with the geochemical features of the coeval igneous rocks from the northern Great Xing'an Range, these results reveal that the existence of an early Carboniferous NE‐trending magmatic arc (ca. 350–330 Ma), extending along the west of the Heihe–Nenjiang–Hegenshan suture zone, gives more constraints on the amalgamation of the Xing'an and Songliao blocks along the Nenjiang–Moguqi areas and indicates that the amalgamation should have terminated by at least the end of the early Carboniferous. [ABSTRACT FROM AUTHOR]

Aim: To investigate the effects of Clostridium butyricum (C. butyricum) on experimental gastric ulcers (GUs) induced by alcohol, restraint cold stress, or pyloric ligation in mice, respectively., Methods: One hundred and twenty mice were randomly allocated into three types of gastric ulcer models (n = 40 each), induced by alcohol, restraint cold stress, or pyloric ligation. In each GU model, 40 mice were allocated into four groups (n = 10 each): the sham control group; model group (GU induction without pretreatment); C. butyricum group (GU induction with C. butyricum pretreatment); and Omeprazole group (GU induction with Omeprazole pretreatment). The effects of C. butyricum were evaluated by examining the histological changes in the gastric mucosal erosion area, the activities of superoxide dismutase (SOD) and catalase (CAT), the level of malondialdehyde (MDA), and the contents of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, leukotriene B4 (LTB4) and 6-keto-PGF-1α (degradation product of PGI2) in the gastric tissue., Results: Our data showed that C. butyricum significantly reduced the gastric mucosal injury area and ameliorated the pathological conditions of the gastric mucosa. C. butyricum not only minimized the decreases in activity of SOD and CAT, but also reduced the level of MDA in all three GU models used in this study. The accumulation of IL1-β, TNF-α and LBT4 decreased, while 6-keto-PGF-1α increased with pretreatment by C. butyricum in all three GU models., Conclusion: Our data demonstrated the protective effects of pretreatment with C. butyricum on anti-oxidation and anti-inflammation in different types of GU models in mice. Further studies are needed to explore its potential clinical benefits.