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Hepatocellular carcinoma (HCC) is the most common primary liver cancer with a poor prognosis. Chemotherapy is one of the first-line clinical therapeutic strategies for HCC. Still, the effectiveness of chemotherapy is hampered by the tumor immunosuppressive microenvironment and drug resistance caused by insufficient delivery. Herein, we developed a metal-drug self-delivery nanomedicine (FDAH) to improve the chemo/chemodynamic therapeutic efficacy of HCC. The core of FDAH is an iron-based nanoparticle chelated with two clinical drugs, Doxorubicin (DOX) and Plerixafor (AMD3100). Additionally, the nanomedicine is externally modified with a Hyaluronic acid (HA) shell, which can prolong the circulation time of the nanoparticles in the bloodstream after intravenous administration. After entering the bloodstream, the nanomedicine reaches the tumor tissue through the EPR effect and is phagocytosed by the tumor cells via HA/CD44-specific interaction. Iron ion-mediated chemodynamic therapy is mediated by the Fenton reaction to generate ROS, causing an imbalance of redox homeostasis within the tumor cells and enhancing the sensitivity of tumor cells to DOX. In addition, AMD3100 intervenes in the CXCL12/CXCR4 axis to influence the infiltration level of immune cells and promote DOX chemotherapy in tumor cells. This work suggests that alleviating immunosuppression via a metal-drug self-delivery system of the CXCR4 inhibitor can effectively improve the DOX chemotherapy and iron ions-mediated chemodynamic therapy.

The recent discovery of superconductivity in infinite-layer nickelates generates tremendous research endeavors, but the ground state of their parent compounds is still under debate. Here, we report experimental evidence for the dominant role of Kondo scattering in the underdoped Nd1−xSrxNiO2thin films. A resistivity minimum associated with logarithmic temperature dependence in both longitudinal and Hall resistivities are observed in the underdoped Nd1−xSrxNiO2samples before the superconducting transition. At lower temperatures down to 0.04 K, the resistivities become saturated, following the prediction of the Kondo model. A linear scaling behavior $\sigma _{{\boldsymbol{xy}}}^{{{\bf AHE}}}{\rm{\ }}\sim{\rm{\ }}{\sigma }_{{\boldsymbol{xx}}}$between anomalous Hall conductivity $\sigma _{{\boldsymbol{xy}}}^{{\bf{AHE}}}$and conductivity ${\sigma }_{{\boldsymbol{xx}}}{\rm{\ }}$is revealed, verifying the dominant Kondo scattering at low temperature. The effect of weak (anti-)localization is found to be secondary. Our experiments can help in clarifying the basic physics in the underdoped Nd1−xSrxNiO2infinite-layer thin films.Experimental evidences for the dominant role of Kondo scattering were discovered in the underdoped Nd1−xSrxNiO2infinite layer superconducting thin films.

ABSTRACTThis study is conducted over a 3 × 3 time–temperature matrix on Ba0.5Sr0.5Co0.8Fe0.2O3−δ(BSCF) ceramics, and sintered bodies above 93% dense are obtained. The electron backscatter diffraction band contrast micrographs of the polished sintered samples are analysed for characterising the grain size distributions (GSDs). This study develops an algorithm for predicting the GSDs of BSCF dependence of sintering condition (time and temperature). In addition, the GSDs predicted by the algorithm agree reasonably with those experimentally observed. When individual grain size is non-dimensionalised by the median grain size, the GSDs data of all BSCF samples reduce to a single self-similar GSD curve. The median grain size is predicted by the classical kinetics equation, Dn = tK0exp(−Q/RT).

This study is conducted over a 3?×?3 time–temperature matrix on Ba0.5Sr0.5Co0.8Fe0.2O3-d(BSCF) ceramics, and sintered bodies above 93% dense are obtained. The electron backscatter diffraction band contrast micrographs of the polished sintered samples are analysed for characterising the grain size distributions (GSDs). This study develops an algorithm for predicting the GSDs of BSCF dependence of sintering condition (time and temperature). In addition, the GSDs predicted by the algorithm agree reasonably with those experimentally observed. When individual grain size is non-dimensionalised by the median grain size, the GSDs data of all BSCF samples reduce to a single self-similar GSD curve. The median grain size is predicted by the classical kinetics equation, Dn?=?tK0exp(-Q/RT).

ABSTRACTThe sintering behaviours of undoped and 8 mol% B-site Ni-doped Ba0.5Sr0.5Co0.8Fe0.2O3−δ(BSCF) under various conditions are systematically investigated. Ni doping increases the lattice parameter of BSCF. The grain size of the undoped BSCF increases from 1.52 to 64.8 μm with increasing sintering temperature from 900 at 1150 °C, while the grain size of the Ni-doped counterpart increases from 3.06 to 34.1 μm as the sintering temperature increases from 1000 to 1200 °C. The grain growth kinetics is analysed using the expression Dn= tK0exp(-Q/RT). The grain growth exponent n is found to be 3 for the undoped BSCF and 4.7 for the Ni-doped BSCF. The grain growth activation energy (Q) is 650.7±30 kJ/mol for the undoped BSCF and 803.4±37 kJ/mol for the Ni-doped BSCF. This indicates that the Ni dopant has a negative influence on the densification and grain growth of BSCF.

The sintering behaviours of undoped and 8 mol% B-site Ni-doped Ba0.5Sr0.5Co0.8Fe0.2O3-d(BSCF) under various conditions are systematically investigated. Ni doping increases the lattice parameter of BSCF. The grain size of the undoped BSCF increases from 1.52 to 64.8 µm with increasing sintering temperature from 900 at 1150 °C, while the grain size of the Ni-doped counterpart increases from 3.06 to 34.1 µm as the sintering temperature increases from 1000 to 1200 °C. The grain growth kinetics is analysed using the expression Dn= tK0exp(-Q/RT). The grain growth exponent n is found to be 3 for the undoped BSCF and 4.7 for the Ni-doped BSCF. The grain growth activation energy (Q) is 650.7±30 kJ/mol for the undoped BSCF and 803.4±37 kJ/mol for the Ni-doped BSCF. This indicates that the Ni dopant has a negative influence on the densification and grain growth of BSCF.

Hedyotis hedyotidea has been used in traditional Chinese medicine for the treatment of autoimmune diseases. However, the mechanisms underlying for the effect remain unknown. We previously showed that, among 11 compounds extracted from H hedyotidea, betulin produced the strongest suppressive effect on T cell activation. Here, we examined the hepatoprotective effects of betulin against acute autoimmune hepatitis in mice and the mechanisms underlying the effects. Freshly isolated mouse splenocytes were stimulated with concanavalin A (Con A, 5 μg/mL) in the presence of betulin, the cell proliferation was assessed with CSFE-dilution assay. Mice were injected with betulin (10, 20 mg·kg−1·d−1, ip) for 3 d. One hour after the last injection, the mice were injected with Con A (15 mg/kg, iv) to induce acute hepatitis. Blood samples and liver tissues were harvested at 10 h after Con A injection, and serum transaminase levels and liver histopathology were detected; serum levels of proinflammatory cytokines, hepatic T lymphocyte ratios, and functional statuses of conventional T and NKT cells were also analyzed. Betulin (16 and 32 μmol/L) dose-dependently suppressed the proliferation of Con A-stimulated mouse splenocytes in vitro. In Con A-challenged mice, preinjection with betulin (20 mg·kg−1·d−1) significantly decreased the levels of proinflammatory cytokines IFN-γ, TNF-α and IL-6, and ameliorated liver injury. Furthermore, pretreatment with betulin (20 mg·kg−1·d−1) significantly inhibited the Con A-induced activation of NKT and conventional T cells, and decreased production of proinflammatory cytokines IFN-γ, TNF-α and IL-6 in these two cell populations. Betulin has immunomodulatory effect on overly activated conventional T and NKT cells and exerts hepatoprotective action in mouse autoimmune hepatitis. The findings provide evidence for the use of H hedyotidea and its constituent betulin in the treatment of autoimmune diseases.