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There has been increasing concern over water pollution, which poses a threat to human life and health. Absorption by low-cost absorbents is considered to be a cost-effective and efficient route. However, the non-reusability of absorbents greatly limits their applications. In this study, a novel vermiculite/TiO2 composite combining the inexpensive absorbent with the commonly used photocatalyst was firstly synthesized via the sol-gel method. On the one hand, the organic pollutants are absorbed by vermiculite and then decomposed through the photocatalysis process, enabling the next round of absorption and creating an absorption–decomposition reusable cycle. On the other hand, the modulation effect of optical and electronic structure on the prepared TiO2 photocatalyst by the vermiculite incorporation could significantly improve the photocatalytic activity and eventually enhance the aforementioned cyclic degradation capacity. The layer-structured vermiculite (Vt) supports a uniform coverage of TiO2 at an optimized ratio, providing an optimal adsorption environment and contact area between the photocatalyst and methylene blue (MB) molecules. Vt/TiO2 heterojunction is formed with Si-O-Ti bonding, at which electrons transfer from Vt to TiO2, enriching electron density in TiO2 and favoring its photocatalytic activity. Furthermore, the incorporation of Vt increases the light absorption of TiO2 in the visible range by narrowing the optical band gap to 1.98 eV, which could promote the generation of photo-excited carriers. In addition, PL measurements revealed that the carrier recombination is substantially suppressed, and the charge separation and migration are greatly enhanced by a factor of 3. As a result, the decomposition rate of MB is substantially increased 5.3-fold, which is ascribed to the synergistic effects of the elevated photocatalysis and the large absorption capacity governed by the chemisorption mechanism of the intra-particle diffusion. These results pave the way for composite design towards efficient, economical, and pragmatic water pollution treatment. [ABSTRACT FROM AUTHOR]

Simple Summary: 5-Fluorouracil (5-FU), in combination with various therapeutic agents, is the main strategy for patients with high risk of stage 2, and advanced stages of, human colorectal cancer. Although 5-FU-based chemotherapy causes myeloid cell suppression, which has long been considered as a major adverse effect in certain cancer patients, recent studies determined that 5-FU selectively kills myeloid-derived suppressor cells (MDSCs), to increase cytotoxic T lymphocyte activation. However, the molecular mechanism underlying 5-FU's suppression of MDSCs is incompletely understood. We report here that 5-FU activates p53, to upregulate Fas expression in MDSCs, to increase MDSC sensitivity to FasL-induced apoptosis in vitro. 5-FU therapy upregulates Fas expression, to suppress MDSC accumulation, to increase CTL tumor infiltration in tumor-bearing mice. In human colorectal cancer patients, 5-FU-based chemotherapy suppresses MDSCs and increases CTLs level. Our findings determine that the p53-Fas pathway links 5-FU to MDSC suppression. Myelosuppression is a major adverse effect of 5-fluorouracil (5-FU) chemotherapy. However, recent findings indicate that 5-FU selectively suppresses myeloid-derived suppressor cells (MDSCs), to enhance antitumor immunity in tumor-bearing mice. 5-FU-mediated myelosuppression may thus have a beneficial effect for cancer patients. The molecular mechanism underlying 5-FU's suppression of MDSCs is currently unknown. We aimed at testing the hypothesis that 5-FU suppresses MDSCs through enhancing MDSC sensitivity to Fas-mediated apoptosis. We observed that, although FasL is highly expressed in T cells, Fas is weakly expressed in myeloid cells in human colon carcinoma, indicating that downregulation of Fas is a mechanism underlying myeloid cell survival and accumulation in human colon cancer. 5-FU treatment upregulated expression of both p53 and Fas, and knocking down p53 diminished 5-FU-induced Fas expression in MDSC-like cells, in vitro. 5-FU treatment also increased MDSC-like cell sensitivity to FasL-induced apoptosis in vitro. Furthermore, we determined that 5-FU therapy increased expression of Fas on MDSCs, suppressed MDSC accumulation, and increased CTL tumor infiltration in colon tumor-bearing mice. In human colorectal cancer patients, 5-FU chemotherapy decreased MDSC accumulation and increased CTL level. Our findings determine that 5-FU chemotherapy activates the p53-Fas pathway, to suppress MDSC accumulation, to increase CTL tumor infiltration. [ABSTRACT FROM AUTHOR]

The identification of the prognostic markers and therapeutic targets might benefit the diagnosis and treatment of pancreatic adenocarcinoma (PAAD), one of the most aggressive malignancies. Vacuolar protein sorting associated protein 26 A (VPS26A) is a candidate prognosis gene for hepatocellular carcinoma, but its expression and function in PAAD remain unknown. The mRNA and protein expression of VPS26A in PAAD was explored and validated by bioinformatics and immunohistochemical analysis. The correlation between VPS26A expression and various clinical parameters, genetic status, diagnostic and prognostic value, survival and immune infiltration were evaluated, and the co-expressed gene-set enrichment analysis for VPS26A was performed. Cytologic and molecular experiments were further carried out to investigate the role and potential mechanism of VPS26A in PAAD. The mRNA and protein levels of VPS26A were elevated in PAAD tissues. High VPS26A expression was associated with the advanced histological type, tumor stage simplified, smoking status and tumor mutational burden score, and the poor prognosis of PAAD patients. VPS26A expression was significantly correlated with immune infiltration and immunotherapy response. VPS26A-co-expressed genes were mainly enriched in the regulation of cell adhesion and actin cytoskeleton and the immune-response-regulating signaling pathway. Our experiments further demonstrated that VPS26A promoted the proliferation, migration and invasion potentials of PAAD cell lines through activating the EGFR/ERK signaling. Our study suggested that VPS26A could be a potential biomarker and a therapeutic target for PAAD through comprehensive regulation of its growth, migration and immune microenvironment. [ABSTRACT FROM AUTHOR]

Research has demonstrated that the formation of composites of titanium dioxide (TiO2) with silver phosphate (Ag3PO4) through the construction of heterojunctions can expand its light absorption range and suppress the recombination of photogenerated electron–hole pairs, thereby improving the photocatalytic performance. However, this method offers only limited performance improvements, and the composite photocatalysts are costly due to the expensive Ag3PO4. In this study, Ti3C2 MXene, which has good hydrophilicity and excellent electrical conductivity, is first used to form Schottky junction composites with bronze TiO2 (TiO2(B)) via electrostatic self-assembly. Then, Ag3PO4 quantum dots were further formed on the surface of the TiO2(B)/Ti3C2 MXene by in situ self-growth, and Ag3PO4 formed heterojunctions and Schottky junctions with TiO2(B) and Ti3C2 MXene, respectively. Finally, a ternary composite photocatalyst TiO2(B)/Ti3C2 MXene/Ag3PO4 was jointly constructed by these functional junctions. Under the synergistic effect of these functional junctions, the mobility and fast separation performance of photogenerated electron–hole pairs of the composite photocatalyst were significantly improved, the recombination of photogenerated electron–hole pairs was effectively suppressed, and the light absorption performance was enhanced. As a result, the composite photocatalyst exhibited excellent photocatalytic performances. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation, as an emerging method to control environmental pollution, is considered one of the most promising environmental purification technologies. As Tibet is a region with some of the strongest solar radiation in China and even in the world, it is extremely rich in solar energy resources, which is ideal for applying photocatalytic technology to its ecological environment protection and governance. In this study, Na2Ti3O7 nanobelts were prepared via a hydrothermal method and converted to TiO2∙xH2O ion exchange, which was followed by high-temperature calcination to prepare TiO2(B) nanobelts ("B" in TiO2(B) means "Bronze phase"). A simple in situ method was used to generate Ag3PO4 particles on the surface of the TiO2 nanobelts to construct a Ag3PO4/TiO2(B) heterojunction composite photocatalyst. By generating Ag3PO4 nanoparticles on the surface of the TiO2(B) nanobelts to construct heterojunctions, the light absorption range of the photocatalyst was successfully extended from UV (ultraviolet) to the visible region. Furthermore, the recombination of photogenerated electron–hole pairs in the catalyst was inhibited by the construction of the heterojunctions, thus greatly enhancing its light quantum efficiency. Therefore, the prepared Ag3PO4/TiO2(B) heterojunction composite photocatalyst greatly outperformed the TiO2(B) nanobelt in terms of photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Emerging evidences link gut microbiota to colorectal cancer (CRC) initiation and development. However, the CRC stage- and spatial-specific bacterial taxa were less investigated, especially in a Chinese cohort, leading to our incomplete understanding of the functional roles of gut microbiota in promoting CRC progression and recurrence. Here, we report the composition and structure of gut microbiota across CRC stages I, II and III, by analyzing the gut mucosal microbiomes of 75 triplet-paired samples collected from on-tumor, adjacent-tumor and off-tumor sites and 26 healthy controls. We observed tumor-specific pattern of mucosal microbiome profiles as CRC progressed and identified ten bacterial taxa with high abundances (>1%) as potential biomarkers for tumor initiation and development. Peptostreptococcus and Parvimonas can serve as biomarkers for CRC stage I. Fusobacterium, Streptococcus, Parvimonas, Burkholderiales, Caulobacteraceae, Delftia and Oxalobacteraceae can serve as biomarkers for CRC stage II, while Fusobacterium, Burkholderiales, Caulobacteraceae, Oxalobacteraceae, Faecalibacterium and Sutterella can serve as biomarkers for CRC stage III. These biomarkers classified CRC stages I, II and III distinguished from each other with an area under the receiver-operating curve (AUC) > 0.5. Moreover, co-occurrence and co-excluding network analysis of these genera showed strong correlations in CRC stage I, which were subsequently reduced in CRC stages II and III. Our findings provide a reference index for stage-specific CRC diagnosis and suggest stage-specific roles of Peptostreptococcus, Fusobacterium, Streptococcus and Parvimonas in driving CRC progression. [ABSTRACT FROM AUTHOR]