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Neoproterozoic igneous and metamorphic complexes occur as tectonic domes in the LongmenMountains of the western margin of the Yangtze Block, and are important in reconstructing the Rodinian supercontinent and constraining the timing and mechanism of tectonic denudational processes. The Pengguan dome consists of granitic intrusions and metamorphic rocks of the Huangshuihe Group and is tectonically overlain by ductilly deformed Sinian to Paleozoic strata. The plutonic intrusions consist of granites with abundant amphibolite enclaves. New LA-ICP-MS zircon U-Pb dating yielded an emplacement age of 809±3 Ma and a protolith age of 844±6 Ma for the granite. The granitic rocks have geochemical signatures typical of A-type granites, indicating their formation under an extensional environment, by melting of newly formed tonalite-trondhjemite-granodiorite (TTG) rocks. A detachment fault, characterized by variable ductile shear deformation of S-C fabric and ESE-ward kinematics, separates the Pengguan dome from the Sinian-Paleozoic cover. 40 Ar/ 39 Ar dating of muscovite from the mylonite in the detachment fault of the dome demonstrates that ductile deformation occurred at ~160 Ma. This study indicates the existence of a Neoproterozoic magmatic arc-basin system, which was denudated by a Jurassic middle crustal ductile channel flow along the Longmenshan thrust belt.

Background/Aims: This study was to investigate the influence of scoparone on pancreatic fibrosis in vitro and in vivo. Methods: Pancreatic stellate cells (PSCs) were isolated from pancreas tissue blocks, and cultured for 3-5 generations for the experiment. PSCs were treated with scoparone in different doses as experimental groups, salvianolic acid B as a positive control and PBS as a blank group. We measured the effects of scoparone on cellular proliferation, oxidative stress, epithelial-mesenchymal transition (EMT), and pancreatic fibrosis. Cellular oxidative stress was detected by using commercially available kits. The impact of scoparone on EMT and fibrosis was detected through immunofluorescence or western blotting. Results: Compared with the control group, scoparone significantly inhibited stellate cell proliferation, and reduced MDA, the expression of mesenchymal makers, and increased the levels of SOD and the expression of E-cadherin (P < 0.05). Western blot analysis showed that scoparone downregulated the expression of TGF-β and p-smad2/3, and upregultated the expression of smad7 (P < 0.05). Conclusion: Scoparone can reduce the levels of oxidative stress, repress pancreatic stellate cells activation, and alleviate fibrosis by regulating TGF-β/Smad pathway.

Morphometric analyses of the immunohistochemical expression of the Clara cell secretory 10-kDa protein (CC10) and surfactant apoproteins A and B (SP-A and -B) were carried out on the developing bronchi and bronchioles of human fetuses and neonates. We analysed the ratio of the number of CC10-positive cells per subepithelial length of the bronchial or bronchiolar basement membrane and found that both the bronchial and the bronchiolar population of CC10-positive cells was significantly higher than that of either SP-A or SP-B. In addition, CC10 was found to be distributed mainly in the bronchiole. CC10-positive cells began to be recognized in the late pseudoglandular phase (15 weeks of gestation) and thereafter gradually increased in the canalicular and terminal sac phases, which correspond to the active development period of the acini or peripheral airways. The earliest expression of SP-A was also noted at 15 weeks of gestation, but its positive epithelial cells were present mainly in the larger bronchi. Double immunohistochemical staining for CC10 and SP-A revealed that the CC10-positive cells lining both the bronchi and bronchioles were different from the SP-A-positive cells. This finding suggests that CC10-positive cells are functionally and developmentally heterogeneous in both fetal and neonatal lungs in humans.

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