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• The Laren dioritic pluton was formed in the Middle Cambrian and has similar geochemical characteristics to high-Mg andesites. • The Laren dioritic pluton was derived from the interaction between the partial melting of the subducted sediment and overlying mantle peridotites. • Cambrian igneous rocks in the North Lhasa terrane were formed in a subduction setting along the northern margin of Gondwana. Late Neoproterozoic and Early Paleozoic igneous events in the Gondwana continental margin remain enigmatic. In this study, we examined U-Pb ages and Hf isotopic compositions of zircon, whole-rock major and trace elements, and Sr-Nd isotope data for diorites from the Laren pluton. Zircon grains from the diorites have U-Pb ages of 509–503 Ma. Diorites are compositionally similar to high-Mg andesites with high SiO 2 (54.3–55.8 wt%), MgO (5.08–8.06 wt%), Cr (83–159 ppm), and Ni (31.9–56.4 ppm) contents and Mg# (68–73). They have low FeOT/MgO (0.78–0.98), TiO 2 , and P 2 O 5 contents and are strongly calc-alkaline. These diorites are rich in Rb, Th, Pb, and Sr in mantle-normalized trace elemental spider diagrams and have chondrite-normalized rare earth element (REE) patterns enriched in light rare earth elements (LREEs). They also have minor Eu anomalies and are extremely depleted in Nb, Ta, and Ti. Geochemically, the Laren pluton resembles arc magmatism. It is also characterized by variable but commonly high whole-rock 87Sr/86Sr(t), with ε Nd (t) values ranging from –2.70 to 1.84 and zircon ε Hf (t) values ranging from –0.2 to –1.1. Detailed analyses of these geochemical characteristics indicate that the primary Middle Cambrian diorite was derived from the interaction between the partial melting of the subducted sediment and overlying mantle peridotites. In combination with the regional geology, the Laren dioritic pluton was most likely placed in an Andean-type active margin related to the subduction of the Proto-Tethys Ocean. Therefore, the results can provide direct evidence of sediment melting during the subduction of the Proto-Tethys Ocean and constrain the Cambrian tectonic evolution of the Lhasa Terrane. [ABSTRACT FROM AUTHOR]

Late Cretaceous igneous rocks in the southern Lhasa subterrane, Tibet, include primitive high-Mg andesites and adakites, which provide important constraints on the tectonic evolution of the Neo-Tethys Ocean. Here, we present detailed zircon U Pb and Hf isotopic and whole-rock geochemical data for granodioritic and dioritic porphyry samples from the Songdo area in the southern Lhasa subterrane. Zircon U Pb dating indicates that the granodiorite crystallized at 88 Ma, whereas the diorite yields ages of 68 and 66 Ma. The granodiorite has adakite-like geochemical characteristics, including high Sr (801–1005 ppm) and low Y (6.8–15.2 ppm) and Yb (0.6–1.3 ppm) concentrations, and high Sr/Y (62–145) and La/Yb (39–93) ratios. We infer that the adakitic granodiorites formed through partial melting of subducted oceanic crust. The dioritic porphyry has intermediate moderate SiO2 (53–58 wt%) and high MgO (5.6–8.2 wt%) contents, and high Mg# (66.4–69.5) values, and is therefore classified as a primitive high-Mg andesite that was derived from interaction between subducted sediment and mantle. The presence of coeval adakite and charnockite, as well as high-temperature granulite-facies metamorphism, indicates that mid-ocean ridge subduction occurred at 100–80 Ma, followed by a 10 Myr hiatus in magmatism and subsequent rollback of the Neo-Tethys slab at 68 Ma. These processes resulted in significant crustal growth within the Lhasa terrane. Unlabelled Image • The ocean ridge subduction of the Neo-Tethys occurred at 100–80 Ma. • The slab rollback of the Neo-Tethys was at 68 Ma and formed sanukitoid. • There was significant crustal growth in Lhasa terrane during the Late Cretaceous. [ABSTRACT FROM AUTHOR]

This article focuses on the Cretaceous structures in the Duolong region, northern Tibet. Our aim was to constrain the metallogenic setting of the Duolong giant porphyry Cu–Au deposit and to discuss the implications for the closure of the Bangong–Nujiang Neo-Tethys Ocean. There are two tectonic stages in the Duolong region, during the Early to Late Cretaceous. The first stage is characterised by numerous large-scale folds and faults with NE–SW compression. The 40 Ar/ 39 Ar plateau age of sericite from mylonite is 127.8 ± 1.1 Ma, which represents the timing of tectonic emplacement of the Jurassic Mugagangri Formation (JM) and ophiolite. This stage corresponds to the northward subduction of the Bangong–Nujiang Neo-Tethys Ocean. The second stage is characterised by the Duolong thrust nappe with a series of sinter deposits, slip surfaces, fault fracture zones, klippes, and tectonic windows. Basalt from the hanging wall yields a zircon U–Pb age of 110.4 ± 1.7 Ma, which is older than the Upper Cretaceous Abushan Formation (K a ) of the footwall. A red layer obtained from drillcores is younger than the overlying Jurassic strata, on the basis of the youngest detrital zircon U–Pb age of 116 ± 2 Ma. This stage is correlated with the closure of the Bangong–Nujiang Neo-Tethys Ocean. We suggest the Upper Triassic Riganpeicuo Formation, JM and ophiolite successively accreted to the southern margin of the South Qiangtang terrane during the Late Jurassic to Early Cretaceous; these constitute the main body of the epicontinental accretionary wedge. This accretionary wedge includes many Early Cretaceous epicontinental arc volcanic rocks and granites, and the Duolong Cu–Au deposits were formed in an Andean-type active continental margin setting. We also conclude that the Bangong–Nujiang Neo-Tethys Ocean closed during the late Early Cretaceous to early Late Cretaceous, and that continental collision continued until the end of the Late Cretaceous. [ABSTRACT FROM AUTHOR]

We report new zircon U–Pb geochronologic and Hf-isotopic data, and whole-rock major and trace element data, for the Labuco granitoids of the southern margin of the Southern Qiangtang terrane (SQ), Tibet. Five intermediate–felsic samples yielded zircon U–Pb ages of 169–156 Ma, making the Labuco granitoids contemporaneous with Middle–Late Jurassic magmatism in the SQ. The granitoids exhibit a range of zircon εHf(t) values from − 7.3 to − 0.6. The samples from Labuco can be divided into low-Sr/Y granitoids (LSG) and high-Sr/Y granitoids (HSG). The LSG are normal calc-alkaline I-type granitoids, characterized by varying major and trace element contents indicative of partial melting of ancient mafic lower crust. The HSG are characterized by high Sr/Y ratios (64–75), (La/Yb) N (chondrite-normalized) ratios of 57–76, and (Gd/Yb) N ratios of 6.6–8.9. These signatures indicate that the HSG were derived by partial melting of garnet-bearing thickened lower crust. The across-arc variation in magma geochemistry in the SQ was caused by tectonic shortening and crustal thickening, which occurred as a result of the northward subduction of the Bangong–Nujiang Ocean lithosphere during the Middle–Late Jurassic. These results have important implications for our understanding of tectonic shortening, crustal thickening, and the geometry of modern and ancient subduction zones. [ABSTRACT FROM AUTHOR]

Protein and cell adhesion on temporary intravascular devices can lead to thrombosis and tissue embedment, significantly increasing complications and device retrieval difficulties. Here, we propose an endothelial glycocalyx-inspired dynamic antifouling surface strategy for indwelling catheters and retrievable vascular filters to prevent thrombosis and suppress intimal embedment. This strategy is realized on the surfaces of substrates by the intensely dense grafting of hydrolyzable endothelial polysaccharide hyaluronic acid (HA), assisted by an amine-rich phenol-polyamine universal platform. The resultant super-hydrophilic surface exhibits potent antifouling property against proteins and cells. Additionally, the HA hydrolysis induces continuous degradation of the coating, enabling removal of inevitable biofouling on the surface. Moreover, the dense grafting of HA also ensures the medium-term effectiveness of this dynamic antifouling surface. The coated catheters maintain a superior anti-thrombosis capacity in ex vivo blood circulation after 30 days immersion. In the abdominal veins of rats, the coated implants show inhibitory effects on intimal embedment up to 2 months. Overall, we envision that this glycocalyx-inspired dynamic antifouling surface strategy could be a promising surface engineering technology for temporary intravascular devices. This study provides an endothelial glycocalyx-mimicking dynamic antifouling surface strategy for temporary intravascular devices. With the synergy of hydrated antifouling surface and durable dynamic interface, this strategy enhances the anti-thrombosis capacities of catheters and suppresses intimal embedment of retrievable vascular filters, representing a promising potential to advance the application of temporary intravascular devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Medicine intervention is the major clinical treatment used to relieve the symptoms and delay the progression of rheumatoid arthritis (RA), but is limited by its poor targeted delivery and short therapeutic duration. Herein, we developed an injectable and bioadhesive gelatin-based (Gel) hydrogel as a local depot of leonurine (Leon)-loaded and folate-functionalized polydopamine (FA-PDA@Leon) nanoparticles for anti-inflammation and chondroprotection in RA. The nanoparticles could protect Leon and facilitate its entry into the M1 phenotype macrophage for intracellular delivery of Leon, while the hydrogel tightly adhered to the tissues in the joint cavity and prolonged the retention of FA-PDA@Leon nanoparticles, thus achieving higher availability and therapeutic efficiency of Leon. In vitro and in vivo experiments demonstrated that the Gel/FA-PDA@Leon hydrogel could strongly suppress the inflammatory response by down-regulating the JAK2/STAT3 signaling pathway in macrophages and protect the chondrocytes from ferritinophagy/ferroptosis. This contributed to maintaining the structural integrity of articular cartilage and accelerating the joint functional recovery. This work provides an effective and convenient strategy to achieve higher bioavailability and long-lasting therapeutic duration of medicine intervention in arthritis diseases. [ABSTRACT FROM AUTHOR]

• Graphene oxide reinforced chitosan composites with chemical interfacial bonding (CN bond) through the EDC reaction was successfully fabricated. • Graphene oxide/chitosan composites with chemical interfacial bonding exhibits improved mechanical properties and biocompatibility. • In vitro cytocompatibility testing demonstrated that the interfacial chemical modifications exhibit no effects on the biocompatibility of the composites. • Chemical bonding modified graphene oxides/chitosan biocomposites exhibit potential applications in tissue engineering. Graphene or graphene oxide reinforced chitosan composites were widely demonstrated to exhibits potential applications in bone tissue engineering for their excellent biocompatibility and osteoinductivity. Nevertheless, the poor mechanical properties that caused by the weak interfacial interactions between graphene or graphene oxide and chitosan limit their applications to a great extent. In the study, graphene oxide reinforced chitosan with chemical interfacial bonding (CN bond) through the amide reaction significantly improved the interfacial interactions and then the mechanical properties of the composites. The compression testing demonstrated effects of the interfacial modification on the mechanical properties of composites. X-ray photoelectron spectroscopy (XPS) results indicated that the new formation of C N bond between graphene oxide and the chitosan matrix. ReaxFF molecular dynamics simulations were carried out to investigate the interactions between graphene oxide and chitosan at the atomistic scale. In vitro cytocompatibility testing demonstrated that the interfacial chemical modifications exhibit no effects on the biocompatibility of the composites. Thus, a meaningful way was proposed in this study to obtain the graphene oxide/chitosan biocomposites for tissue engineering with improved mechanical properties and excellent biocompatibility. [ABSTRACT FROM AUTHOR]

Abstract: Previous investigations have indicated that the Changning–Menglian (CMSZ) and Longmu Co–Shuanghu (LSSZ) suture zones represent the Paleo-Tethys Ocean of northern Tibet and western Yunnan of China, respectively. However, our understanding of the Paleo-Tethys suture zone in eastern Tibet seems to be incomplete. The North Lancangjiang suture zone (NLSZ) has been hypothesized to mark the Paleo-Tethys Ocean in eastern Tibet. The present study reports new zircon U–Pb ages and Hf isotope data, and whole-rock major and trace element data from the gneissic granites from the Jitang complex in the Leiwuqi area of the NLSZ in order to verify this hypothesis. Six samples of gneissic granites yielded weighted mean 206Pb/238U ages of 249–237Ma. The geochemical data show that the gneissic granites are characterized by high SiO2 (70.79–77.75wt.%); K2O (2.00–6.13wt.%); low A/CNK values (<1.1); enrichment in Rb, Th, Ba, and Pb; depletion in Nb, Ta, Sr, Ti, and P; and negative Eu anomalies. These features suggest that the gneissic granites were high-potassium, calc-alkaline, and I-type granites. Moreover, the zircon εHf(t) values (from −2.7 to +2.5) and TC DM model ages (1447–1009Ma) indicate that they were generated by the partial melting of the Meso-proterozoic juvenile crust. These gneissic granites were interpreted to have formed in the post-collisional tectonic setting related to the closure of the Paleo-Tethys Ocean. By combining previously published and the new data, we propose that the NLSZ connects the LSSZ and CMSZ in the Tibetan plateau, and marks a Paleo-Tethys Ocean basin in eastern Tibet. [Copyright &y& Elsevier]

Highlights: [•] Cambrian metarhyolites emplaced in the central Lhasa subterrane of southern Tibet. [•] The metarhyolites were derived from anatexis of Proterozoic metasedimentary rocks. [•] The metarhyolites formed under a subduction environment. [•] The Gondwanan proto-Tethyan margin was interpreted as an active continental margin. [Copyright &y& Elsevier]

Immunotherapy is a powerful way to treat cancer, however, systemic treatment-associated adverse effects remain a major concern. In this study, a bioadhesive injectable hydrogel is developed to provide localized immune niches for tumor microenvironment immunomodulation and cancer catalytic immunotherapy. First, a phenolic single atom nanozyme (SAN) was developed by in situ synthesis of Pd single atom on catechol-grafted carbon-quantum-dot (DA-CQD@Pd) templates. Then, the bioadhesive injectable hydrogel consisting of DA-CQD@Pd SAN and immune adjuvant CpGODN was formed through SAN-catalyzed free-radical polymerization. The SAN exhibited peroxidase-like activity to generate ROS and kill tumor cells through catalytic therapy. The hydrogel locally released CpGODN in a sustained manner, which limited the risk of systemic exposure, reducing the impact of CpGODN toxicity, and protecting CpGODN from degradation. The bioadhesive hydrogel immobilized around solid tumor to provide an immune response site after injection. When combined it with the administration of immune checkpoint inhibitor anti-PD-L1, the hydrogel realized localized immunomodulation, maximized therapeutic efficacy and prevents tumor metastasis via a catalytic immunotherapy. [ABSTRACT FROM AUTHOR]

The preparation of HA/PPy/ZnO nanocomposite coating on titanium substrate with bioactive, physiological stable, antibacterial, angiogenic and osteoinductive properties. • Pulse electrochemical deposition method for preparing polypyrrole. • PPy as a dual regulator of hydroxyapatite and ZnO nanoparticles. • Nano-coating with anti-infection, angiogenic and osteoinductivity. • Reduced the release rate of Ca2+ and Zn2+ from the nano-coating. Titanium and titanium alloys have been widely used in orthopedics and related fields. However, their clinical applications are limited due to the lack of anti-infection, osteoinductivity and angiogenic ability. In the present study, we utilized pulse electrochemical deposition method to prepare polypyrrole (PPy) by the in-situ oxidative polymerization of pyrrole (Py), and through the coordination and doping of ions, the function of PPy as a dual regulator of hydroxyapatite nanoparticles (HA-NPs) and zinc oxide nanoparticles (ZnO-NPs) was achieved. Bioactivity test showed that the composite coating could induce the formation of apatite, and the apatite was in a neat arrangement preferentially grew along the (002) crystal plane, indicating good bioactivity. The release test showed that the dual regulation effect of PPy coordination and doping reduced the release rate of Ca2+ and Zn2+ from the composite coating. Antibacterial tests showed that the composite coating against Escherichia coli and Staphylococcus aureus. Besides, bone marrow-derived mesenchymal stem cells (BMSCs) exhibited good adhesion, proliferation and differentiation on the composite coating, and fluorescence staining experiments demonstrated good osteoinductivity of the composite coating. In this study, a multifunctional composite coating with anti-infection, angiogenic and osteoinductivity was successfully constructed on the titanium surface via pulse electrochemical deposition method. [ABSTRACT FROM AUTHOR]