Rational design of MOF@COF composites with multi-site functional groups for enhanced elimination of U(VI) from aqueous solution.

Both environment and human beings were menaced by the widespread application of radioactive uranium, high-performance and effective elimination of uranium from wastewater is of important meaning for development of environmental sustainability in the future. In this study, the water-stable MOF material and the highly crystalline COF were compounded by a mild hydrothermal strategy, which achieved efficient removal of U(VI) through the synergistic effect. The composites showed the characteristics of both COFs and MOFs, which will possess higher stability, larger surface area and faster adsorption efficiency that cannot be carried out by a single component. Batch experiments and characterizations (SEM, TEM, XRD, FT-IR, BET, XPS, etc.) indicated that UiO-66-NH2@LZU1 had more stable and multi-layer pore structure and rich active functional groups. The Langmuir model and the pseudo-second-order kinetics fitting was more suitable for the U(VI) elimination process. The greatest uranium adsorbing capacity of UiO-66-NH2@LZU1 (180.4 mg g-1) was observed to exceed the UiO-66-NH2 (108.8 mg g-1) and COF-LZU1 (65.8 mg g-1), which reached the excellent hybrid effects. Furthermore, FT-IR and XPS analyses confirmed that the most nitrogen-containing group from COF-LZU1 and oxygen-containing group of UiO-66-NH2 could be combined with U(VI). In addition, electrostatic interaction was also a mechanism during the removal process. This work displayed that UiO-66-NH2@LZU1 was a prospective hybrid material for radioactive waste remediation. The compound method and application mentioned in this work had provided a theoretical basis for designing and developing multi-functional composite adsorbents, which contributed to the development of new materials for radioactive wastewater treatment technologies.

Highly efficient extraction of uranium from seawater by polyamide and amidoxime co-functionalized MXene.

Uranium mainly exists in the form of uranyl carbonate in seawater. [UO2(CO3)3]4- has strong stability, which increases the difficulty of uranium extraction from seawater. Meanwhile, the complex marine environment, a large number of coexisting competing ions and biological pollution are all non-negligible disturbing factors. Herein, we introduced amidoxime (AO) groups into the surface of Ti3C2 and grafted polyamides (PA) by a simple one-step hydrothermal method to produce an efficient seawater uranium extraction adsorbent Ti3C2-AO-PA. Owing to the amidoxime groups, the material was highly selective for uranium. And the large number of amino groups in the polyamides gave it ideal resistance to biofouling. The possibility of Ti3C2-AO-PA as an adsorbent for uranium extraction from seawater was confirmed by various characterization techniques, numerous adsorption batch experiments, simulated seawater experiments and antibacterial performance tests. It was demonstrated that the uptake of [UO2(CO3)3]4- by Ti3C2-AO-PA showed fast reaction kinetics (about 120 min), brilliant absorption capacity (81.1 mg·g-1 at pH 8.3), significant high selectivity (32.8 mg-U/g-Ads) and outstanding anti-biological contamination performance (92.9% antibacterial rate). XPS and DFT further indicated that the high extraction ability of Ti3C2-AO-PA for uranium was mainly attributed to the strong complexation of AO and -NH2 with [UO2(CO3)3]4-. These conclusions showed that Ti3C2-AO-PA not only had an ideal application prospect for uranium extraction from seawater, but also provided an available strategy for rapid and selective uranium adsorption from real seawater.

A fungal-modified material with high uranium (VI) adsorption capacity and strong anti-interference ability.

With open-chain polyether as the bridge chain, a new fungal-modified material with diamidoxime groups was prepared by a series of uncomplex synthesis reaction. The orthogonal experiment obtained its optimized adsorption conditions as follows: the initial pH value of 6.5, the initial uranyl concentration of 40 mg L-1, the contact time of 130 min, and the a solid-liquid ratio of 25 mg L-1. The maximum adsorption capacity of target material was 446.20 mg g-1, and it was much greater than that of the similar monoamidoxime material (295.48 mg g-1). The linear Langmuir (R2 = 0.9856) isotherm models and the linear pseudo-second-order kinetic model (R2 = 0.9931) fit the experimental data of uranium (VI) adsorption better, indicating the adsorption mechanism should mainly be the monolayer adsorption and chemical process. In addition, the relevant experiments exhibited the prepared material had the good reusability, which reached 84.25% of the maximum capacity after five cycles, and the excellent anti-interference performance. The above features suggest the modified fungus material will have the good application prospect in the future.

Tanshinone IIA attenuates AOM/DSS-induced colorectal tumorigenesis in mice via inhibition of intestinal inflammation.

CONTEXT: Tanshinone IIA is a natural extract derived from a Chinese medicinal herb with multiple bioactivities; however, whether and how tanshinone IIA protects against colorectal cancer (CRC) are uncertain. OBJECTIVE: We investigated the potential beneficial effects of tanshinone IIA in a colitis-associated colorectal tumorigenesis mouse model and its underlying mechanisms. MATERIALS AND METHODS: Male C57BL/6 mice were treated with azoxymethane (AOM) 10 mg/kg body weight and dextran sulphate sodium (2.5% DSS) to induce a colitis-associated cancer model. Tanshinone IIA (200 mg/kg body weight) was given to the mice intraperitoneally. After 12 weeks, all mice were sacrificed to measure tumour formation, intestinal permeability, neutrophil infiltration, and colonic inflammation. In addition, whether tanshinone IIA has inhibitory effects on neutrophil activation was determined through in vitro investigations. RESULTS: We observed that tanshinone IIA significantly decreased tumour formation in AOM/DSS-treated mice compared to AOM/DSS-treated alone mice (0.266 ± 0.057 vs. 0.78 ± 0.153, p = 0.013). Tanshinone IIA also decreased intestinal permeability compared to that in AOM/DSS-treated alone mice (3.12 ± 0.369 vs. 5.06 ± 0.597, p = 0.034) and consequently reduced neutrophil infiltration of the colonic mucosa (53.25 ± 8.85 vs. 107.6 ± 13.09, p = 0.014) as well as intestinal inflammation in mice. Mechanistically, tanshinone IIA downregulated the NF-κB signalling pathway in the colonic tumours of AOM/DSS-treated mice. In vitro assays further validated that tanshinone IIA suppressed LPS-induced neutrophil activation. CONCLUSION: These data suggest that tanshinone IIA alleviates colorectal tumorigenesis through inhibition of intestinal inflammation. Tanshinone IIA may have a therapeutic potential for CRC in clinical practice.

N2 fixation in urbanization area rivers: spatial-temporal variations and influencing factors.

While nitrogen (N2) fixation is an important process in nitrogen (N) biogeochemical cycling, supplying a significant portion of the N in natural ecosystems, few quantitative constraints exist concerning its contribution to the N enrichment and export from river ecosystems. This study estimates the N2 fixation rates of urban rivers in the Yangtze Estuary area using acetylene reduction. The results demonstrate that the prominent spatiotemporal variability of river N2 fixation rates is driven by various environmental factors. River N2 fixation rates are significantly higher in the summer (90.57 ± 14.60 ngN·L-1·h-1) than in the winter (57.98 ± 15.73 ngN·L-1·h-1). Spatially, rivers draining urban and suburban areas have higher N2 fixation rates than those draining rural areas. The N2 fixation rates are positively correlated with the N2 fixing cyanobacteria density, water temperature, light, and the water phosphorus (P) concentration, but they are negatively correlated with the dissolved N concentration (NH4+-N and NO3--N). The N2 fixation rates annually range from 53.20 to 89.24 ngN·L-1·h-1 for all of the sampling rivers, which is equivalent to a depth integrated (0-0.6 m) N input of 0.163-0.274 gN·m-2·a-1. The determined annual N input via N2 fixation is generally higher than that of marine systems, but it is lower than that of eutrophic lakes. This study provides robust evidence that N2 fixation can supply a substantial portion of the N input to human-impacted river ecosystems, which has not been sufficiently accounted for when determining the N mass balance of riverine ecosystems. A high N2 fixation rate may increase the ratio of N to P input to river systems, and therefore render P the limiting factor in aquatic eutrophication.

Study on the Protective Effect of Special Electromagnetic Field Treated Water and Far Infrared Rays on LPS-Induced ARDS Rats.

OBJECTIVE: To explore the protective effect of special electromagnetic field treated water (SEW) and far infrared rays (IFR) on endotoxin (lipopolysaccharide, LPS) induced ARDS rats and the effect on inflammatory factors. METHODS: 40 healthy male SD rats were randomly divided into 4 groups with 10 in each group. Preventive experiment: Adaptive feeding was carried out for 1 week according to animal feeding standards. Rats in SEW group drank SEW daily. Samely, rats in SEW and FIR group also drank SEW daily. Besides, rats in SEW and FIR group were also given far infrared rays for 20min/d. Rats in model group drank distilled water daily. After 7 days, rats in each group were injected with LPS (2 mg/kg) via the tail vein for making models. Rats in blank control group were given distilled water for 7 days, without modeling. All rats in the 4 groups were put to death under anesthesia 16 hours after modeling. Lung tissue and abdominal aortic blood were taken from these rats. RESULTS: Pathological observation of lung and lung tissue indicated that rats in model group showed great pathological difference from rats in blank group. Rats in intervention group showed more symptomatic improvement in relation to alveolar and pulmonary interstitial congestion, edema, and inflammatory cell infiltration than rats in model group. The level of inflammatory factors like IL-1ß and IL-6 in serum of rats in model group increased compared to blank control group (p<0.05). Comparing SEW group and SEW and FIR group with model group, levels of IL-1ß and IL-6 in serum of rats both decreased remarkably (IL-Iß: P < 0.05; IL-6: P < 0.01) while there was no obvious difference between SEW group and SEW and FIR group (p>0.05). The lung coefficient (LI) in SEW and FIR group was significantly lower than that in model group (P<0.01), which was higher than that of blank control group (P < 0.05), while there was no obvious difference between model group and SEW group (P>0.05). Compared with blank control group, lung permeability index (LPI) in model group showed no obvious difference (P>0.05). CONCLUSION: Special electromagnetic field treated water and far infrared rays can alleviate lung tissue damage of endotoxin-induced ARDS rats, relieving symptoms of alveolar and pulmonary interstitial congestion, edema, and inflammatory cell infiltration. The protective effect of special electromagnetic field treated water and far infrared rays on endotoxin-induced acute respiratory distress syndrome may result from their role in reducing the levels of IL-1ß and IL-6 in serum and the expression level of p65 protein in lung tissue, in addition to reliving inflammatory response, lung coefficient, and lungs edema.

Tumor Size Improves the Accuracy of the Prognostic Prediction of Lymph Node-Negative Gastric Cancer.

BACKGROUND: Tumor size has been regarded as the "T" stage of many solid tumors because of its effect on prognosis. However, the prognostic impact of tumor size in gastric cancer (GC) is still controversial. MATERIALS AND METHODS: A total of 436 patients with curatively resected GC and those without lymph node metastasis in our center were retrospectively enrolled. The appropriate cutoff points for tumor size were determined. Potential prognostic factors were analyzed. In addition, a pathological tumor-size (pTS) classification system was proposed to evaluate the superiority of its prognostic prediction of node-negative GC patients compared with that of the pT staging system. RESULTS: The ideal cutoff points for tumor size were 4 and 8 cm. In the multivariate analysis, tumor size was identified as an independent prognostic factor for node-negative GC patients after surgery, as was pT stage. The pTS classification was found to be more appropriate for predicting the overall survival of node-negative GC patients after curative surgery than pT stage, and the -2 log-likelihood of the pTS classification (1680.782) was smaller than the value of pT (1695.239). CONCLUSIONS: As an independent prognostic factor, tumor size should be incorporated into the pT staging system to enhance the accuracy of the prognostic prediction of node-negative GC patients.

Synergistic effect of magnetic nanoparticles of Fe(3)O(4) with gambogic acid on apoptosis of K562 leukemia cells.

Gambogic acid (GA) has a significant anticancer effect on a wide variety of solid tumors. Recently, many nanoparticles have been introduced as drug-delivery systems to enhance the efficiency of anticancer drug delivery. The aim of this study was to investigate the potential benefit of combination therapy with GA and magnetic nanoparticles of Fe(3)O(4) (MNPs-Fe(3)O(4)). The proliferation of K562 cells and their cytotoxicity were evaluated by MTT assay. Cell apoptosis was observed and analyzed by microscope and flow cytometry, respectively. Furthermore, real-time polymerase chain reaction and Western blotting analyses were performed to examine gene transcription and protein expression, respectively. The results showed that MNPs-Fe(3)O(4) dramatically enhanced GA-induced cytotoxicity and apoptosis in K562 cells. The typical morphological features of apoptosis treated with GA and MNPs-Fe(3)O(4) were observed under an optical microscope and a fluorescence microscope, respectively. The transcription of caspase-3 and bax gene in the group treated with GA and MNPs-Fe(3)O(4) was higher than that in the GA-alone group or MNPs-Fe(3)O(4)-alone group, but the transcription of bcl-2, nuclear factor-kappaB, and survivin degraded as did the expression of corresponding proteins in K562 cells. Our data suggests a potential clinical application of a combination of GA and MNPs-Fe(3)O(4) in leukemia therapy.