Thin-wall hollow porous cystic-like graphitic carbon nitride with awakened n→π* electronic transitions and exceptional structural features for superior photocatalytic degradation of sulfamethoxazole.

Effective photoexcitation and carrier migration are the essential aspects to strengthen semiconductor-engaged redox reaction. Herein, a three-dimensional thin-wall hollow porous cystic-like g-C3N4 (HPCN) with curved layer edge was successfully fabricated via a non-template thermal-condensation strategy. The construction of unique distorted structure can evoke the hard-to-activate n→π* electronic transition to some extent, broadening the absorption spectrum to 800 nm. And benefiting from the multiple reflections of incident light, the effective photoactivation can be further achieved. Moreover, the thin-wall porous framework can shorten the diffusion distance and accelerate migration of photogenerated charge, favouring interfacial redox reactions. The optimized HPCN1.0 demonstrated an excellent photocatalytic degradation of SMX under blue-LED light irradiation, which was dramatically superior to that of pristine g-C3N4 (CN, 11.4 times). Ultimately, in consideration of reactions under several influencing factors with four different water samples, we demonstrated that the HPCN photocatalyst could be utilized far more productively for the elimination of SMX under real-world aqueous conditions. This work provides a straightforward approach for the removal of SMX and has immense potential to contribute to global scale environmental remediation.

[Targeted imaging ability of a biotinylated imaging probe Biotin-S-S-Rhodol for breast cancer cells in vitro].

OBJECTIVE: To investigate performance of a biotinylated imaging probe 3a for targeted imaging of breast cancer cells. METHODS: Ultraviolet absorption spectrum and fluorescence spectrum were employed to analyze the spectral characteristics of 3a. The fluorescence spectrums of 3a treated with different concentrations of glutathione (GSH) were obtained to determine the sensibility of 3a to GSH. Flow cytometry was used to determine the cellular uptake of 3a by MCF-7 cells, MDA-MB-231 cells and Hs 578Bst cells in the presence or absence of biotin, and the imaging performance of 3a in the 3 cell lines was assessed under an inverted fluorescent microscope. The toxicity of 3a to the cells was evaluated using MTT method. RESULTS: 3a showed the strongest absorption peak at 510 nm, and its fluorescence emission signal was the strongest at 544 nm. As the concentration of GSH increased (0-6 mmol/L), 3a exhibited an increasing fluorescence signal at 544 nm. The cellular uptake of 3a was markedly higher in MDA-MB-231 cells and MCF-7 cells than in Hs 578Bst cells. The imaging studies showed that 3a had a good breast cancer cell-targeting property and produced clear images under fluorescent microscope. MTT assay demonstrated no obvious toxicity of 3a in Hs 578Bst cells even at the concentration of 20 µmol/L, but MCF-7 cells and MDA-MB-231 cells exposed to 2-20 µmol/L 3a showed a lowered cell viability. CONCLUSION: 3a is capable of targeted imaging of breast cancer cells mediated by biotin. 3a at the concentration of 2-20 µmol/L has minimal cytotoxicity to normal breast cells but can lower the viability of breast cancer cells.

Rapid expansion of cytomegalovirus-specific cytotoxic T lymphocytes by artificial antigen-presenting cells expressing a single HLA allele.

Cytomegalovirus (CMV) is a major threat in patients undergoing allogeneic bone marrow transplantation. The adoptive transfer of CMV-specific cytotoxic T lymphocytes (CTLs) expanded from the blood of CMV-seropositive donors has been shown to effectively control CMV infection. However, the requirement for safe and effective antigen-presenting cells (APCs) for each patient precludes broad applicability of this successful form of therapy. Here we analyze the ability of artificial APCs (AAPCs) to activate and expand CMV-specific CTLs from peripheral blood of seropositive HLA A2.1+ donors. We demonstrate that AAPCs expressing the CMV P495 peptide or the full-length pp65 protein stimulate P495-specific CTLs at least as effectively as autologous, peptide-pulsed, peripheral blood mononuclear cells or EBV-transformed B cells. Starting from 100 mL of blood, the AAPCs reliably yield clinically relevant CTL numbers after a single stimulation. CTLs activated on AAPCs effectively kill CMV-infected fibroblasts and have a Tc1 memory effector phenotype identical to that of CTLs generated with autologous APCs. AAPCs thus offer a rapid, controlled, convenient, and highly reproducible system for expanding CMV-specific CTLs. Furthermore, the CTL expansion obtained with AAPCs encoding full-length pp65 indicates that AAPCs may be used to present known as well as unknown CTL epitopes in the context of the AAPC's HLA.