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The temperature-dependent optical properties of lanthanide-doped phosphors have been enthusiastically investigated in the fields of biomedicine, night-vision security, and optical information storage. In this work, the dynamically varying temperature-dependent photoluminescence and long persistent luminescence at low temperature (4–250 K) in the CaSrNb2O7:Pr3+ phosphor are explored. The photoluminescence of CaSrNb2O7:Pr3+ is white and the matrix emits cyan at 470 nm under 325 nm excitation at 84 K, whereas the CaSrNb2O7:Pr3+ phosphor exhibits bright red long persistent luminescence for more than 400 s at 250 K. Moreover, the CaSrNb2O7:Pr3+ exhibits a dramatic photoluminescence transition from white to red as the temperature rises by thermal quenching and the trap compensation luminescence. This optical property at low temperature shows great superiority not only in biomedicine and cryotherapy as a means of visualizing safe and non-toxic detection but also opens up new opportunities in the field of space remote sensing superconductivity. [ABSTRACT FROM AUTHOR]

In solid tumors, tumor invasion and metastasis account for 90 % of cancer‐related deaths. Cell migration is steered by the lamellipodia formed at the leading edge. These lamellipodia can drive the cell body forward by its mechanical deformation regulated by cofilin. Inhibiting cofilin activity can cause significant defects in directional lamellipodia formation and the locomotory capacity of cell invasion, thus contributing to antimetastatic treatment. Herein, a near infrared light (NIR)‐controlled nanoscale proton supplier was designed with upconversion nanoparticles (UCNPs) as a core coated in MIL‐88B for interior photoacids loading; this photoacids loading can boost H+ transients in cells, which converts the cofilin to an inactive form. Strikingly, inactive cofilin loses the ability to mediate lamellipodia deformation for cell migration. Additionally, the iron, which serves as a catalyticaly active center in MIL‐88B, initiates an enhanced Fenton reaction due to the increased H+ in the tumor, ultimately achieving intensive chemodynamic therapy (CDT). This work provides new insight into H+ transients in cells, which not only regulates cofilin protonation for antimetastatic treatment but also improves chemodynamic therapy. [ABSTRACT FROM AUTHOR]

Background: Intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and three-dimensional arterial spin labeling (3D-ASL) have been applied to brain tumors; however, the relationship between their parameters and the Ki-67 labeling index (Ki-67 LI) for the grading of gliomas have yet to be investigated.Purpose: The aim of this study is to compare multiple parameters obtained from IVIM-DWI and 3D-ASL with the Ki-67 LI when grading gliomas.Material and Methods: Fifty-two patients with pathologically confirmed gliomas had undergone magnetic resonance imaging (MRI), including IVIM-DWI and 3D-ASL imaging. Mann-Whitney U tests were conducted and receiver operating characteristic (ROC) curves were generated to determine parameters for distinguishing high-grade gliomas (HGGs) from low-grade gliomas (LGGs). These parameters included the apparent diffusion coefficient (ADC), true diffusivity (D), pseudo diffusivity (D*), perfusion fraction (f), cerebral blood flow (CBF), and their relative values (rADC, rD, rD*, rf, and rCBF). Spearman correlation analysis was used to assess the correlations of the parameters of MRI with the Ki-67 LI.Results: The rADC, rD, and rf were significantly lower in HGGs than in LGGs (P < 0.005 for all). The rD had a significantly greater area under the ROC curve than that of the other parameters in the differentiation of HGGs from LGGs (P < 0.05). Both the rD and rf were moderately negatively correlated with the Ki-67 LI.Conclusion: Both the rD and rf can be used for the quantitative prediction of the Ki-67 LI. Among the extracted parameters, the rD had the significantly greatest diagnostic efficacy. [ABSTRACT FROM AUTHOR]

Due to biological safety and negligible toxicity, nitric oxide (NO) therapy has gained increasing interest in the field of cancer therapy during the past few years. However, individual NO cancer therapy normally exhibited limited therapeutic efficiency. In order to acquire satisfactory therapeutic outcomes, the NO therapy is usually combined with other therapeutic treatments, mostly chemotherapy. Herein, we constructed HA-TPP@NORM nanoparticles based on the co-assembly of an NO donor (NORM) and tetraphenylporphyrin (TPP)-modified hyaluronic acid, which can efficiently generate a highly biocidal molecule of peroxynitrite (ONOO−) via the synergistic interactions of the nitric oxide (NO) therapy and photodynamic therapy (PDT) to enhance the cancer therapeutic efficiency. In addition, MTT results exhibited that without light irradiation, the HA-TPP@NORM nanoparticles have favourable biocompatibility with the cell viability above 95% at the maximum TPP concentration (20 μg mL−1). Under simultaneous irradiation with 365 nm and 650 nm light, ONOO− can be efficiently produced in cancer cells via the direct coupling reaction of the generated NO and superoxide anion radical (O2˙−), which significantly enhanced the anticancer effect, when compared with individual NO therapy or PDT therapy. Therefore, the HA-TPP@NORM nanoparticles may provide a new insight into the design of efficiently NO-related cancer therapeutic systems. [ABSTRACT FROM AUTHOR]

From 2006 to 2011, with the change in regulatory policies, most regions of China relaxed restrictions on the intercity branching of city commercial banks, which led to a significant increase in the number of nonlocal branches of city commercial banks. We assess the impact of this bank branching deregulation on the credit risk of the regional banking sector across 286 prefecture-level cities in China. We find that deregulation has increased the credit risk of the regional banking sector in host cities by intensifying competition and encouraging risk-taking behaviors such as "lowering lending criteria" and "attracting deposits with higher interest". Moreover, this effect becomes more pronounced in regions with a higher initial level of the loan-to-deposit ratio and regions with a higher initial level of competition in the banking sector. • Branching deregulation increases the credit risk of the regional banking sector. • The reason is that competition encourages more risk-taking behaviors. • Lowering lending criteria is one of the most typical risk-taking behaviors. • This effect is more pronounced in cities with a higher loan-to-deposit ratio. [ABSTRACT FROM AUTHOR]

Two-step catalytic pyrolysis of Nannochloropsis sp (NS) was conducted with SBA-15 and ZSM-5. Thermogravimetric analyzer (TG) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) were used to investigate the effects of SBA-15 and ZSM-5 on the two-step pyrolysis of NS. The comparative study showed that ZSM-5 and SBA-15 had different effects on the pyrolysis characteristic of NS because of their different property. ZSM-5 had no effects on the kinetic mechanism, but SBA-15 obviously changed DTG curves and the reaction order of the low temperature pyrolysis stage. SBA-15 increased the contents of amines and alkanes to 19.40% and 5.62% in the first step compared with those of the one-step pyrolysis (1.95% and 1.83%). Due to the stronger acid sites, ZSM-5 improved the content of olefins (33.79%) and esters (10.79%) in the first step and the contents of nitriles (11.75%) and aromatic hydrocarbons (31.01%) in the second step compared with those of one-step pyrolysis (10.61%, 5.41%, 0.00%, 8.42%). Acid catalyst had no positive effects on the generation of N-heterocyclic compounds. This study is expected to provide a reference for the efficient pyrolysis utilization of microalgae. [Display omitted] • Two-step pyrolysis (TSP) of microalgae over different catalysts was compared. • Selectivities of amines and alkanes were increased by TSP coupled with SBA-15. • Contents of olefins, nitriles and aromatics were improved by TSP coupled with ZSM-5. • Effects of catalyst property on the two-step pyrolysis of microalgae were analyzed. [ABSTRACT FROM AUTHOR]

Background: The immunosuppressive microenvironment in glioma induces immunotherapy resistance and is associated with poor prognosis. Glioma-associated mesenchymal stem cells (GA-MSCs) play an important role in the formation of the immunosuppressive microenvironment, but the mechanism is still not clear. Results: We found that GA-MSCs promoted the expression of CD73, an ectonucleotidase that drives immunosuppressive microenvironment maintenance by generating adenosine, on myeloid-derived suppressor cells (MDSCs) through immunosuppressive exosomal miR-21 signaling. This process was similar to the immunosuppressive signaling mediated by glioma exosomal miR-21 but more intense. Further study showed that the miR-21/SP1/DNMT1 positive feedback loop in MSCs triggered by glioma exosomal CD44 upregulated MSC exosomal miR-21 expression, amplifying the glioma exosomal immunosuppressive signal. Modified dendritic cell-derived exosomes (Dex) carrying miR-21 inhibitors could target GA-MSCs and reduce CD73 expression on MDSCs, synergizing with anti-PD-1 monoclonal antibody (mAb). Conclusions: Overall, this work reveals the critical role of MSCs in the glioma microenvironment as signal multipliers to enhance immunosuppressive signaling of glioma exosomes, and disrupting the positive feedback loop in MSCs with modified Dex could improve PD-1 blockade therapy. [ABSTRACT FROM AUTHOR]