Synthesis and Upconversion Luminescence Fine-tuning of Yb3+/Ho3+-Doped Indium and Gallium Oxide Nanoparticles.

Rare earth (RE) dopants can modulate the bandgap of oxides of indium and gallium and provide extra upconversion luminescence (UCL) abilities. However, relevant UCL fine-tuning strategies and energy mechanisms have been less studied. In this research, InGaO, Ho3+ monodoped and Yb3+/Ho3+ codoped In2O3, and Ho3+ monodoped Yb3Ga5O12 nanoparticles (NPs) were synthesized by a solvothermal method. The effects of Yb3+ and Ho3+ dopants on the crystal structures, UCL properties, and optical bandgaps of the oxides were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UCL spectroscopy, and measurements of decay times, pump power dependence, and transmittance spectra. The crystal structures of oxide products of indium and gallium were significantly modified with RE dopants. In2O3 and Yb3Ga5O12 were selected as the host materials. For Yb3+/Ho3+ codoped In2O3 NPs, there existed energy transfers from the defect states of In2O3 to Ho3+ and from Yb3+ to Ho3+. With a fixed Ho3+ concentration, In2O3:0%Yb3+,2%Ho3+ NPs showed the optimal UCL properties mainly due to In2O3-Ho3+ energy transfer and Ho3+-Yb3+ energy-back-transfer, while with a fixed Yb3+ concentration, In2O3:5%Yb3+,3%Ho3+ NPs with a slight Yb2O3 impurity and Yb3Ga5O12:2%Ho3+ NPs did mainly due to Ho3+-Ho3+ cross-relaxation. Besides, the optical bandgaps of In2O3 and Yb3Ga5O12 were noticeably broadened with RE dopants. These findings can offer feasible directions for the synthesis and UCL fine-tuning of RE-doped oxides of indium and gallium and improve their multifunction application prospects in the fields of semiconductor and UCL nanomaterials.

Biological factors driving colorectal cancer metastasis.

Approximately 20% of colorectal cancer (CRC) patients present with metastasis at diagnosis. Among Stage I-III CRC patients who undergo surgical resection, 18% typically suffer from distal metastasis within the first three years following initial treatment. The median survival duration after the diagnosis of metastatic CRC (mCRC) is only 9 mo. mCRC is traditionally considered to be an advanced stage malignancy or is thought to be caused by incomplete resection of tumor tissue, allowing cancer cells to spread from primary to distant organs; however, increasing evidence suggests that the mCRC process can begin early in tumor development. CRC patients present with high heterogeneity and diverse cancer phenotypes that are classified on the basis of molecular and morphological alterations. Different genomic and nongenomic events can induce subclone diversity, which leads to cancer and metastasis. Throughout the course of mCRC, metastatic cascades are associated with invasive cancer cell migration through the circulatory system, extravasation, distal seeding, dormancy, and reactivation, with each step requiring specific molecular functions. However, cancer cells presenting neoantigens can be recognized and eliminated by the immune system. In this review, we explain the biological factors that drive CRC metastasis, namely, genomic instability, epigenetic instability, the metastatic cascade, the cancer-immunity cycle, and external lifestyle factors. Despite remarkable progress in CRC research, the role of molecular classification in therapeutic intervention remains unclear. This review shows the driving factors of mCRC which may help in identifying potential candidate biomarkers that can improve the diagnosis and early detection of mCRC cases.

Chemical compounds, anti-tumor and anti-neuropathic pain effect of hemp essential oil in vivo.

Hemp (Cannabis sativa L.), an annual dioecious plant, has shown extensive application in the fields of fibers, food, oil, medicine, etc. Currently, most attention has been paid to the therapeutic properties of phytocannabinoids. However, the pharmaceutical research on essential oil from hemp is still lacking. In this study, hemp essential oil (HEO) was extracted from hemp flowers and leaves, and the components were analyzed by GC-MS. Quatitative analysis of three main compounds ß-caryophyllene, ß-caryophyllene oxide, α -humulene were determined by GC-FID. The anti-tumor and anti-neuropathic pain effects of HEO were evaluated. In the paclitaxel induced neuropathic mice model, HEO reduced the serum level of inflammatory cytokines TNF-α to achieve the analgesic effect, which was tested by evaluating mechanical and thermal hyperalgesia. Further investigation with cannabinoid receptor 2 (CB2 R) antagonist AM630 revealed the mechanism of reversing mechanical hyperalgesia may be related to CB2 R. In Lewis lung cancer grafted mice model, the tumor growth was significantly inhibited, the levels of tumor inflammatory cytokines TNF-α and IL-6 were downregulated, immune organ index was modified and immune-related CD4+, CD8+ T lymphocytes level, CD4+/CD8+ ratio were increased when administered with HEO. These results reveal that HEO plays a role not only in tumor chemotherapy induced peripheral neuropathy treatment, but also in anti-tumor treatment which offers key information for new strategies in cancer treatment and provides reference for the medicinal development of hemp.

Pressure-induced photoluminescence enhancement of CeF3:Tb3+ nanoparticles.

Rare earth fluorides have been widely used in recent years in the field of solid-state lighting. However, the relationship between the structure and luminescence properties is still unclear. Herein, the photoluminescence and structural transition of CeF3:Tb3+ nanoparticles under high pressure were investigated through in situ photoluminescence and X-ray diffraction measurements. Intriguingly, the photoluminescence of CeF3:Tb3+ nanoparticles displays an enhancement from 18.3 to 33.4 GPa, accompanied by the phase transition from the starting hexagonal phase to the orthorhombic phase. It was found that the distance of luminescent centers increased sharply during the high-pressure phase transition, which weakened the quenching effect and improved transmission efficiency. Our work provides more insight into the optical characteristics and structures of rare earth trifluorides.

[Raman characterization of high-pressure phase transition in AlN nanowires].

High-pressure phase transition of AlN nanowires was investigated in the range of 0-33.1 GPa by in situ Raman spectrum method in diamond anvil cell (DAC). The A1 (LO) vibration mode exhibits considerably asymmetry and broadening, indicating the occurrence of wurtzite-to-rocksalt phase transition. The Raman signal of high-pressure phase can be assigned to the disorder activated Raman scattering of rocksalt AlN. After fully releasing pressure, the Raman characterization of high-pressure phase was quenched. According to the pressure dependence of phonon frequency of AlN nanowires, the difference of transiton path between AlN nanowires and bulk materials was discussed and the mode Grüneisen parameters were determined.

Cetuximab combined with cisplatin improves the prognosis of gastric cancer patients and its effect on P38 MAPK expression.

PURPOSE: To observe the clinical efficacy of cetuximab combined with cisplatin in gastric cancer patients, and to explore its potential mechanism so as to provide references for clinical chemotherapeutic drugs for gastric cancer. METHODS: A total of 122 gastric cancer patients undergoing chemotherapy in our hospital from August 2014 to June 2017 were enrolled and divided into cetuximab group (n=64) and cetuximab + cisplatin group (n=58) according to the chemotherapy regimen. The clinical efficacy, prognosis, adverse reactions and immune status were compared between the two groups of patients. At the same time, the expressions of serum gastric cancer markers, carcinoembryonic antigen (CEA) and vascular endothelial growth factor (VEGF) in both groups of patients were detected before and after treatment. In addition, the P38 protein expression level in cancer tissues in both groups of patients was detected via Western blotting before and after treatment. RESULTS: The total effective rate of clinical efficacy was 66.41 and 82.55%, respectively, in cetuximab group and the cetuximab + cisplatin group (p<0.05). The mortality and tumor metastasis rates were 16.5% vs. 3.4% and 12.3% vs. 4.5%, respectively, in the cetuximab group and the cetuximab + cisplatin group (p<0.05). The percentages of cluster of differentiation 3 (CD3), CD4, CD8, CD4/CD8 and T cell metastasis rate after treatment were significantly increased in the cetuximab + cisplatin group (p<0.05), but significantly declined in the cetuximab group (p<0.05). In addition, the levels of serum CEA and VEGF in both groups were significantly decreased (p<0.05), but they declined more significantly in the cetuximab + cisplatin group. Furthermore, it was found that cetuximab + cisplatin group had a stronger phosphorylation ability of P38 in gastric cancer tissues than the cetuximab group (p<0.05). CONCLUSIONS: Compared with cetuximab alone, cetuximab combined with cisplatin can significantly improve the clinical efficacy, reduce the tumor metastasis rate, enhance the immune function and improve the prognosis of gastric cancer patients, whose mechanism may be related to the activation of P38 in gastric cancer tissues.