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The late Neoarchean tonalite – trondhjemite – granodiorite (TTG) and mafic rocks record essential information regarding the early tectonic evolution of the North China Craton, which is crucial for understanding the onset and development of the plate tectonic regime. In this study, we present a comprehensive analysis of petrography, geochronology, and geochemistry of the Guanghua Mélange from the Tonghua area in NE China. The mélange comprises basalt, gabbro, pyroxene diorite, and trondhjemite, and is classified into three groups: basaltic – gabbroic rocks (Group #1), dioritic rocks (Group #2), and trondhjemites (Group #3). Zircon U-Pb analyses indicate that they formed at 2596–2550 Ma, 2531–2515 Ma, and 2502 Ma, respectively, with metamorphism occurring during ~ 2500–2450 Ma. Meanwhile, geochemical data indicate that the calc – alkaline basaltic rocks (Group #1) exhibit slight depletion of Nb or Ta with weakly negative Eu anomalies, suggesting derivation from the lithospheric mantle and formation within a continental arc environment. The pyroxene diorites (Group #2) display similar geochemical characteristics to Group #1, likely formed by partial melting of depleted mantle that underwent sgignificant metasomatism due to variable amounts of slab-derived fluids or melts. The tholeiitic granitoids (Group #3) exhibit strongly fractionated chondrite-normalized REE patterns with high (La/Yb)N and Sr contents, low Y contents, and depletion of Nb, Ta or Ti, resembling adakites generated in arc setting, indicating likely formation through partial melting of subducted oceanic crust. This process was controlled by the initial plate tectonics under a higher geothermal gradient. Consequently, when combined with previous findings, we conclude that an initial subduction of oceanic plate operated in the northeastern North China Craton during the late Neoarchean (>2.55 Ga). Subsequently, it transformed into modern-type plate tectonics during ~ 2.55–2.53 Ga, eventually followed by the continent-continent collision at ~ 2.50–2.45 Ga, resulting in the formation of the Ji – Liao – Ji (Jilin – Liaoning – Hebei) Collision Orogenic Belt. [ABSTRACT FROM AUTHOR]

Dendrobium nobile is an important orchid plant that has been used as a traditional herb for many years. For the further pharmaceutical development of this resource, a combined transcriptome and metabolome analysis was performed in different parts of D. nobile. First, saccharides, organic acids, amino acids and their derivatives, and alkaloids were the main substances identified in D. nobile. Amino acids and their derivatives and flavonoids accumulated strongly in flowers; saccharides and phenols accumulated strongly in flowers and fruits; alkaloids accumulated strongly in leaves and flowers; and a nucleotide and its derivatives and organic acids accumulated strongly in leaves, flowers, and fruits. Simultaneously, genes for lipid metabolism, terpenoid biosynthesis, and alkaloid biosynthesis were highly expressed in the flowers; genes for phenylpropanoids biosynthesis and flavonoid biosynthesis were highly expressed in the roots; and genes for other metabolisms were highly expressed in the leaves. Furthermore, different members of metabolic enzyme families like cytochrome P450 and 4-coumarate-coA ligase showed differential effects on tissue-specific metabolic accumulation. Members of transcription factor families like AP2-EREBP, bHLH, NAC, MADS, and MYB participated widely in differential accumulation. ATP-binding cassette transporters and some other transporters also showed positive effects on tissue-specific metabolic accumulation. These results systematically elucidated the molecular mechanism of differential accumulation in different parts of D. nobile and enriched the library of specialized metabolic products and promising candidate genes. [ABSTRACT FROM AUTHOR]

The central Inner Mongolia, located at the intersection of the northern margin of the North China Craton (NCC) and the Central Asian Orogenic Belt, is crucial for deciphering the Late Palaeozoic tectonic evolution associated with the subduction and closure of the Palaeo‐Asian Ocean (PAO). Our study focused on petrology, detrital zircon LA–ICP–MS U–Pb geochronology and whole‐rock geochemistry for the Late Carboniferous to Permian sandstones within the Shuanmazhuang, Dahongshan, Naobaogou, and Laowopu formations in Siziwang Banner, central Inner Mongolia. This comprehensive analysis shed light on the dynamic interplay between the NCC and the South Mongolia Block. Detrital zircon U–Pb ages in investigated samples mainly cluster between 250 and 2650 Ma, with significant peaks at 2.4–2.5 Ga, 1.8–2.0 Ga, 400–430 Ma, and 250–320 Ma, respectively. The geochemistry data are characterized by SiO2 contents (56.29–77.95 wt. %), Na2O / K2O ratios (0.45–1.58) and SiO2/Al2O3 ratios between 4.33 and 7.44. Moreover, they exhibit the slight enrichment in large ion lithophile elements (Rb and Ba) and the depletion in high field strength elements (Nb, Ta, Th, and U). These facts indicate that the sedimentary detritus predominantly originates from felsic sources, probably deriving from the Late Carboniferous–Permian continental island arc‐related intermediate‐acid igneous rocks, the Late Ordovician‐Silurian magmatic rocks in the Bainaimiao arc and the basements of the NCC. Furthermore, our present results also suggest that during the Early–Middle Permian, accelerating oceanic crust subduction triggered significant magmatic events in Siziwang Banner, leading to rapid uplift and the erosion of arc magmatic rocks, as well as the abundant corresponding sediments. Subsequently, the gradual convergence and eventual collision between the NCC and the Southern Mongolian Block took place at the end of the Permian, representing final closure of the PAO. [ABSTRACT FROM AUTHOR]

Housing prices in China have risen dramatically in recent decades, giving rise to bubble concerns. Many studies show that short-term regulation of real estate market is ineffective, which drove central government to propose the construction of a long-term mechanism for real estate in late 2016. However, few studies have been conducted to estimate its effects. This article highlights the effects of the long-term mechanism on housing prices, similar to a quasi-natural experiment, with the proposal of the long-term mechanism. In this context, the study was conducted with the end of 2016 as a breakpoint, using the RDiT method and panel data for 35 large- and medium-sized cities from 2009 to 2021, to find out whether the long-term mechanism has stabilized housing prices or not. The results reveal that the long-term mechanism dramatically reduced the divergence and dispersion of housing prices from the long-term equilibrium level. Further study shows that there is significant heterogeneity in the impact of the long-term mechanism on housing prices across cities, with significant effects in second-tier cities but not in first-tier cities, and with significant effects in central and western cities but not in eastern cities. Therefore, we suggest that the eastern, including the first-tier cities, remain the focus of the construction of the long-term mechanism in the future, and continue to implement short-term regulation for key cities, and build a system that coordinates with the long-term mechanism. [ABSTRACT FROM AUTHOR]

Typical ophiolitic rock assemblages such as siliciclastic rocks, basalts and gabbros, together with the subduction-related intermediate-acidic intrusive rocks, are newly discovered in the Tongjiang-Fuyuan area of the Heilongjiang Provence, NE China. To determine the formation age and genesis of the mafic rocks (basalts and gabbros) and intermediate-acidic intrusive rocks (granodiorites) in the area, as well as their geodynamic settings, the whole-rock geochemical analysis and zircon LA-ICP-MS U-Pb dating were carried out. Zircon U-Pb results suggest that the granodiorites are 93–95 Ma and gabbro is 95 Ma, respectively. Geochemical results show that the gabbros and basalts exhibit characteristics of ocean island basalt (OIB) affinity and are typically related to having originated from mantle plumes. While the granodiorites show the nature of the island-arc magmatic rocks and may originate from the lower crust. Based on the coeval igneous rock associations and regional tectonic evolution, we conclude that the late Cretaceous magmatic rocks in the Tongjiang-Fuyuan area are the product of continuous subduction of the Palaeo-Pacific plate and reflect the subduction rollback process of the Palaeo-Pacific plate. [ABSTRACT FROM AUTHOR]

The medicinal plant Dendrobium nobile is an important natural antioxidant resource. To reveal the antioxidants of D. nobile, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was employed for metabolic analysis. The H2O2-induced oxidative damage was used in human embryonic kidney 293T (H293T) cells to assess intracellular antioxidant activities. Cells incubated with flower and fruit extracts showed better cell survival, lower levels of reactive oxygen species (ROS), and higher catalase and superoxide dismutase activities than those incubated with root, stem, and leaf extracts (p < 0.01). A total of 13 compounds were newly identified as intracellular antioxidants by association analysis, including coniferin, galactinol, trehalose, beta-D-lactose, trigonelline, nicotinamide-N-oxide, shikimic acid, 5′-deoxy-5′-(methylthio)adenosine, salicylic acid, isorhamnetin-3-O-neohespeidoside, methylhesperidin, 4-hydroxybenzoic acid, and cis-aconitic acid (R2 > 0.8, Log2FC > 1, distribution > 0.1%, and p < 0.01). They showed lower molecular weight and higher polarity, compared to previously identified in vitro antioxidants in D. nobile (p < 0.01). The credibility of HPLC-MS/MS relative quantification was verified by common methods. In conclusion, some saccharides and phenols with low molecular weight and high polarity helped protect H293T cells from oxidative damage by increasing the activities of intracellular antioxidant enzymes and reducing intracellular ROS levels. The results enriched the database of safe and effective intracellular antioxidants in medicinal plants. [ABSTRACT FROM AUTHOR]

Increasing data has confirmed the potential anticancer properties of Dendrobium, a traditional Chinese herb. However, most anticancer compositions from the plant of Dendrobium were usually extracted by high polar solvent, while weak polar compositions with excellent anticancer activity remained largely unexplored. In this study, the differences between ether extract and ethanol extract of Dendrobium nobile Lindl. on chemical components and anticancer activities were investigated, as well as the anticancer mechanisms among different extracts. The results demonstrated that the ether extract exhibited a stronger anticancer effect than ethanol extract, and its anticancer effect was mainly due to weak polar compounds rather than polysaccharides and alkaloids. Quantitative proteomics suggested that the ether extract significantly stimulated the over-expression of immature proteins, the endoplasmic reticulum stress and unfolded protein response were subsequently induced, the intracellular reactive oxygen species level was seriously elevated, and oxidative stress occurred in the meanwhile. Eventually, autophagy and apoptosis were activated to cause cell death. Our findings demonstrate that the ether extract of D. nobile is a potential candidate for anticancer drug development, and that future research on anticancer drugs derived from medicinal plants should also concentrate on weak polar compounds. [ABSTRACT FROM AUTHOR]

Dendrobium nobile is a beautiful orchid and a widely used medicinal plant. In vitro antioxidant assays suggested that D. noblie flower extracts showed significantly higher 2, 2′-azinobis-3-ethylbenzthiazoline-6-sulfonate (ABTS) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging rates and much more ferric-reducing power than those of root, stem, leaf and fruit. To better understand the antioxidant basis of D. nobile flower, high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was used for metabolic identification and quantification. Finally, there were 72 metabolites among the total of 712 identified components showed significant association (coefficient >0.8, p < 0.05) with ABTS scavenging rates, DPPH scavenging rates, and ferric-reducing power. The three enriched classes of flower metabolites, including amino acids and their derivatives, organic acids and their derivatives, and flavonoids, formed the main antioxidant basis. The significantly accumulated rutin, astragalin, isomucronulatol-7-O-glucoside, quercetin 4′-O-glucoside, methylquercetin O-hexoside, caffeic acid, caffeic acid O-glucoside, and p-coumaric acid (Log2(fold change) >2, p < 0.01 , distribution in flower >0.1%) made a key contribution to the higher antioxidant activities in flower. The relative quantification results of HPLC-MS/MS were verified by the common quantification methods. The antioxidant basis revealed of D. nobile flower will be helpful in the production of healthy or beauty products. [ABSTRACT FROM AUTHOR]

Dendrobium liquor obtained by soaking Dendrobium in Chinese liquor is considered as a health drink in China. Here, we found the pretreatment of extract of Dendrobium nobile Lindl. liquor (DNLE) attenuated the oxidative damage to cells caused by H2O2, while the abilities of DNLE of eliminating extracellular free radicals and promoting the activities of intracellular antioxidant enzymes were observed. Quantitative proteomics identified 375 differentially expressed proteins caused by H2O2 treatment in 293T cells. However, only 12 differentially expressed proteins were found in DNLE‐pretreated cells which under the same oxidative damage. This suggested that the pretreatment of DNLE could suppress the disorder of protein expressions caused by oxidative stress which could induce cell death. Besides, DNLE was helpful for avoiding the unfolded protein response (UPR) and cell cycle disorder caused by oxidative stress. Taken together, these results demonstrated that Dendrobium liquor could be a healthy herbal drink with antioxidant function. Practical applications: Dendrobium is used as an edible herb and a tonic food in traditional Chinese medicine. Dendrobium liquor obtained by soaking Dendrobium with Chinese liquor is also regarded as a nourishing health drink. However, there is rare research data on biological activity of Dendrobium liquor. Our current results demonstrated that the extract of Dendrobium nobile Lindl. liquor (DNLE) possessed the ability of eliminating free radicals in/out the human cells. More importantly, DNLE could help cells to resist the interference on cell life activities caused by oxidative stress. Since many evidences suggested that oxidative stress is linked to human disease and aging, and chemical antioxidant has some side effects on health, Dendrobium liquor can serve as a natural health drink with antioxidant function. Furthermore, the active ingredients in DNLE also possess the potential to be developed as natural antioxidant additive in food and cosmetics. [ABSTRACT FROM AUTHOR]

Resveratrol (Res) is a type of natural plant stilbenes and phytoalexins that only exists in a few plant species. Studies have shown that the Res could be biosynthesized and accumulated within plants, once the complete metabolic pathway and related enzymes, such as the key enzyme resveratrol synthase (RS), existed. In this study, a RS gene named PNRS1 was cloned from the peanut, and the activity was confirmed in E. coli. Using transgenic approach, the PNRS1 transgenic rice was obtained. In T3 generation, the Res production and accumulation were further detected by HPLC. Our data revealed that compared to the wild type rice which trans-resveratrol was undetectable, in transgenic rice, the trans-resveratrol could be synthesized and achieved up to 0.697 μg/g FW in seedlings and 3.053 μg/g DW in seeds. Furthermore, the concentration of trans-resveratrol in transgenic rice seedlings could be induced up to eight or four-fold higher by ultraviolet (UV-C) or dark, respectively. Simultaneously, the endogenous increased of Res also showed the advantages in protecting the host plant from UV-C caused damage or dark-induced senescence. Our data indicated that Res was involved in host-defense responses against environmental stresses in transgenic rice. Here the results describes the processes of a peanut resveratrol synthase gene transformed into rice, and the detection of trans-resveratrol in transgenic rice, and the role of trans-resveratrol as a phytoalexin in transgenic rice when treated by UV-C and dark. These findings present new outcomes of transgenic approaches for functional genes and their corresponding physiological functions, and shed some light on broadening available resources of Res, nutritional improvement of crops, and new variety cultivation by genetic engineering. [ABSTRACT FROM AUTHOR]