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Objective To establish an animal model and evaluation system for lymph node metastasis of breast cancer. Methods A total of 60 female BALB/c mice (6~8 weeks old) were subjected, and then 6 models of lymph node metastasis (n=10) were constructed through injection at different parts in the mice with cell suspension of 4T1 breast cancer cells.Transgenic mice (n=5) of mouse mammary tumor virus-polyoma middle T antigen (MMTV-PyMT) were employed and served as model of spontaneous tumor metastasis.Then the advantages and disadvantages of different lymph node metastasis models were comprehensively evaluated from multiple aspects, such as operability, histomorphology and pathological detection, tumor growth rate and mouse survival. Results Among the 7 metastasis models, 4 models of lymph node metastasis were successfully established.Among them, the PyMT mouse spontaneous tumorigenesis model showed the best clinical reproduction, with a tumorigenesis rate of up to 100%, but had a disadvantage of poor experimental standardization.The hind paw-popliteal lymph node model had the fastest lymph node metastasis, easy operation and high repeatability, and a tumorigenesis rate of 100%, indicating its suitable for lymph node metastasis related research.The thigh subcutaneous-inguinal lymph node model also successfully simulated lymph node metastasis, with simple operation and high repeatability, a tumorigenesis rate of up to 100%, but its metastasis time was slightly longer than the hind paw-popliteal lymph node model.The inguinal lymph node-contralateral lymph node model was also a successful lymph node metastasis model, but with difficult operation, only 50% tumor-bearing rate, and poor repeatability.Lymph node metastasis model was not successfully established in the other 3 tumor-bearing models (under the tongue-internal jugular scapular tongue muscle lymph node model, bone marrow-inguinal lymph node model and right upper back skin-axillary lymph node model) in a short time, with no tumor cells observed in the pathological sections. Conclusion Through the comprehensive comparison of multiple models, mouse hind paw-popliteal lymph node model is the most suitable for conducting related research.

Objective To explore the sensitizing effect of manganese for radiotherapy against tumors and its possible mechanisms. Methods A total of 300 male C57BL/6 mice (6~8 weeks old, weighing 20~23 g) with subcutaneous tumor were randomly divided into 4 groups: control group, radiotherapy group, manganese treatment group, and combined radiotherapy and manganese treatment group. Nasal drip with 10 μg manganese adjuvant was applied to the mice from the latter 2 groups on day 9 of tumor bearing, then single dose of 20 Gy radiation was locally administered on day 10. Tumor growth and mouse survival were monitored regularly. The sensitizing effect of manganese on radiotherapy was determined by monitoring and comparing the tumor growth among different unilateral mouse models. Bilateral tumor-bearing model was used to examine the effect of manganese on abscopal effects induced by radiotherapy. Flow cytometry was used to illustrate the changes in tumor-infiltrating immune cells in unilateral tumor bearing model. Immunohistochemical staining was employed to evaluate the spleen function in unilateral tumor bearing mice. Results Based on repeated validation of 3 different unilateral tumor-bearing models, radiotherapy combined with manganese therapy significantly inhibited tumor growth and prolonged survival of mice (P < 0.05). The results of bilateral tumor-bearing model showed that manganese therapy enhanced abscopal effects of radiotherapy, and significant regression was observed in both side of tumor under radiotherapy or not (P < 0.05). Flow cytometry revealed that manganese further increased radiation-induced CD8+T infiltration (P < 0.05) and decreased radiation-induced infiltration of Treg cells and myeloid-derived suppressor cells (MDSCs) (P < 0.05). Furthermore, manganese increased lymphocyte reserve pool of the spleen and improved its function. Conclusion Manganese adjuvant could act as a sensitizing agent for radiotherapy, by improving the function of spleen and reprogramming the tumor microenvironment synergistically.

Most of the optical behaviors in photoelectric multifunctional ceramics strongly depend on the addition of rare‐earth elements. However, the limited species of rare‐earth cations available as luminescence centers restrict the further development of photoelectric devices. Additionally, introducing the large atomic‐radii elements usually dramatically deteriorates the piezoelectric properties. Herein, the novel photochromism and luminescence modulation properties have been realized in CuO‐doped [(K0.43Na0.57)0.94Li0.06][(Nb0.94Sb0.06)0.95Ta0.05]O3 (KNLNST) piezoelectric ceramics which show intense sensitivity to visible‐light irradiation. As a strategy for regulating oxygen vacancy concentrations in piezoelectric ceramics, different CuO amounts are doped to generate color centers for photochromism. The photoluminescence phenomenon exhibiting green emission under 375 nm excitation is observed in KNLNST piezoelectric ceramics, which is most commonly realized via rare‐earth doping in luminescent materials. KNLNST–0.3CuO ceramics with the highest oxygen vacancy concentration achieve a reversible luminescence modulation of 46.9% by altering light irradiation and thermal stimulus. Moreover, a hand‐rewritable optical information test demonstrates exceptional reproducibility and fatigue durability. This research displays the controllable photochromism and luminescence behaviors in ceramics via regulating oxygen vacancy concentration by CuO "hard" doping. The lead‐free high performance photoelectric ceramics fulfill the demands of potential applications in anti‐counterfeiting and optical storage devices. [ABSTRACT FROM AUTHOR]

Potassium sodium niobate (KNN)‐based piezoelectric ceramics have emerged as a promising alternative to lead‐based systems due to their exceptional properties. While extensive research has focused on improving the electrical properties of KNN‐based ceramics through doping and processing optimization, the concurrent investigation of their mechanical properties has been lacking. This study presents a comprehensive analysis of the mechanical and electrical properties of KNN‐based lead‐free piezoceramics doped with various transition metal oxides and rare earth oxides, based on substantial experimental data. Our findings reveal that the as‐sintered KNN‐based ceramics exhibit not only outstanding electrical properties but also remarkable mechanical robustness compared to conventional toughened lead zirconate titanate (PZT)‐based ceramics. These exceptional electrical and mechanical properties are attributed to the micro‐scale and atomic‐scale structure of the modified KNN‐based ceramics, characterized by a highly condensed structure, an inhomogeneous distribution of nano‐domain structure, and the presence of amorphous intergranular films at grain boundaries. [ABSTRACT FROM AUTHOR]

Memristors are a candidate device for artificial neural systems due to their excellent conductance‐regulation ability and potential to simulate the characteristics of biological synapses. This study fabricated a Pt/TaOx/TiOy/Ti analog artificial synapse memristor that exhibits excellent multilevel storage property with a large on/off ratio of ≈660 times. The dynamic resistive switching mechanism is well expounded and validated by the reset stopping voltage dependent Schottky fitting results. Moreover, the essential biological synaptic characteristics such as long‐term potentiation/depression (LTP/D) and paired‐pulse facilitation (PPF) are successfully mimicked with a low pulse energy consumption of 12.69 nJ. A neuromorphic network constructed on the enhanced symmetry and linearity of conductance for this Pt/TaOx/TiOy/Ti memristive device can achieve 92.45% accuracy in recognizing handwritten pattern. These results demonstrate a significant potential for application Pt/TaOx/TiOy/Ti memristor in non‐volatile memory and bioinspired neuromorphic systems. [ABSTRACT FROM AUTHOR]

Simultaneous achievement of large piezoelectric responses and broad service temperature range for power-type applications, such as sensors, actuators and transducers, is challenging due to trade-off between piezoelectric coefficient (d33) and Curie temperature (TC). In this study, manganese dioxide (MnO2) was introduced in 0.04BiYbO3-0.96Pb(Zr0.469Ti0.531)O3 (BY-PZT) matrix, and then based on this, Qm further was improved and tan δ got reduced via optimization of Zr/Ti ratios in the matrix, i.e., by intentional design of Ti nonstoichiometry for inhibiting pyrochlore phase. Results show that doping of appropriate amount of MnO2 led to significant increase in Qm of BY-PZT ceramics from 160 to 274, and tan δ decreased from 2% to 0.3%, while nonstoichiometry with certain Ti-deficiency amount could further increase Qm to 567 and reduce tan δ to 0.2%. Simultaneously, TC was still maintained at relatively high level for high-temperature applications. Ceramics with optimized composition of 0.04BiYbO3-0.96Pb(Zr0.469Ti0.531–1.5%)O3 + 1.3 mol%MnO2 sintered at 1100 °C exhibited optimal electrical properties of d33 = 252 pC·N−1, kp = 0.468, Qm = 567, tan δ = 0.2%, and TC = 389 °C. This study solves the problem of generation of pyrochlore phase during mass production of BY-PZT-based ceramics, and results pave the way for utilizing new power-type piezoelectric ceramic in high-temperature applications. [ABSTRACT FROM AUTHOR]