Yapei Yang

Abstract The novel coronavirus disease 2019 (COVID-19) has grown to be a global public health emergency since patients were first detected in Wuhan, China. Thus far, no specific drugs or vaccines are available to cure the patients with COVID-19 infection. The immune system and inflammation are proposed to play a central role in COVID-19 pathogenesis. Mesenchymal stem cells (MSCs) have been shown to possess a comprehensive powerful immunomodulatory function. Intravenous infusion of MSCs has shown promising results in COVID-19 treatment. Here, we report a case of a severe COVID-19 patient treated with human umbilical cord Wharton’s jelly-derived MSCs (hWJCs) from a healthy donor in Liaocheng People’s Hospital, China, from February 24, 2020. The pulmonary function and symptoms of the patient with COVID-19 pneumonia was significantly improved in 2 days after hWJC transplantation, and recovered and discharged in 7 days after treatment. After treatment, the percentage and counts of lymphocyte subsets (CD3 + , CD4 + , and CD8 + T cell) were increased, and the level of IL-6, TNF-α, and C-reactive protein is significantly decreased after hWJC treatment. Thus, the intravenous transplantation of hWJCs was safe and effective for the treatment of patients with COVID-19 pneumonia, especially for the patients in a critically severe condition. This report highlights the potential of hWJC infusions as an effective treatment for COVID-19 pneumonia.

Compared with semiconductor quantum dots and organic chromophores, carbon dots (CDs)-based lysosome probe with strong emission, an intrinsic targeting ability, and easy synthesis procedure were urgently desired in visualization imaging studies. Herein, we showed that it was possible to produce CDs with the desired properties for lysosome imaging via a one-step hydrothermal treatment of commercial reagents, rose bengal (RB) and branched polyethylenimine (bPEI). The prepared bPEI-RB CDs (P-R CDs) had a high fluorescence quantum yield (FLQY) of 90.49%, a narrow emission band of 30 nm, negligible phototoxicity, and dark toxicity. Moreover, P-R CDs had an intrinsic lysosome targeting ability without any postmodification of the ligands. Long-term cell imaging displayed P-R CDs can anchor lysosomes for up to 48 h without leakage. In addition, experimental results confirmed that dehalogenation cross-linking and structural reorganization of the reactants were the main causes of the ultrahigh photoluminescence efficiency, low cytotoxicity, and passivated surface of the P-R CDs. This origin was attributed to the restricted intersystem crossing and nonradiative transition, the reduced production of singlet oxygen, and suitable —NH2 functional groups. Due to outstanding characteristics, P-R CDs may be developed for a promising tool in lysosome images. The concept of facile preparation will also pave a new avenue for developing ultrabright functional nanomaterial markers.

BACKGROUND: Cellular immunotherapy has been widely used in the treatment of solid tumors. However, the clinical application of cord blood-derived dendritic cells and cytokine-induced killer cells (CB-DC-CIK) for the treatment of gastric cancer has not been frequently reported. In this study, the efficacy and safety of CB-DC-CIK for the treatment of gastric cancer were evaluated both in vitro and in vivo. METHODS: The phenotypes, cytokines, and cytotoxicity of CB-DC-CIK were detected in vitro. Patients with advanced gastric cancer were divided into the following two groups: the experimental group (CB-DC-CIK combined with chemotherapy) and the control group (chemotherapy alone). The curative effects and immune function were compared between the two groups. RESULTS: First, the results showed that combination therapy significantly increased the overall disease-free survival rate (P=0.0448) compared with chemotherapy alone. The overall survival rate (P=0.0646), overall response rate (P=0.410), and disease control rate (P=0.396) were improved in the experimental group, but these changes did not reach statistical significance. Second, the percentage of T-cell subsets (CD4(+), CD3(-)CD56(+), and CD3(+)CD56(+)) and the levels of IFN-γ, TNF-α, and IL-2, which reflect immune function, were significantly increased (P<0.05) after immunotherapy. Finally, no serious side effects appeared in patients with gastric cancer after the application of cellular immunotherapy based on CB-DC-CIK. CONCLUSION: CB-DC-CIK combined with chemotherapy is effective and safe for the treatment of patients with advanced gastric cancer.

Porous silicon (PS) has been widely used in solar cells and photodetectors because of its very low reflectance. However, its properties are greatly influenced by its morphological characteristics. In this work, PS samples with different morphologies were prepared by electrochemical etching with different fabrication parameters (etching time, current density, and solution composition). There were cracks microstructures on the surface of PS and their shapes were affected by different fabrication parameters. A crack model was established to analyze the formation mechanism of the surface morphology. The influence of different fabrication parameters on the surface morphology and the infrared spectrum of PS were analyzed. The morphological and optical properties of PS with a composite structure were studied. The results indicated that PS with composite structure can promote the oxidation reaction while significantly reducing the reflectance.