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Here, the catalytic and degradation effect of nickel nanoparticles (NiNPs) on triethanolamine (TEA) with CO2 at 20 °C and 50 °C and a range of TEA concentrations (3–30 wt%) was studied. We show that TEA absorption rate of CO2 can be enhanced with NiNPs, the maximum enhancement was 8.3% when compared to a control solution found at 50 °C with 30 wt% TEA alone. Additionally, the time for TEA to be fully loaded with CO2 is reduced; compared to the control, NiNPs enhanced solutions were up to 26.3% faster. Also, to the best of our knowledge, this is the first time the degradation of TEA with NiNPs has been studied. TEA was subject to both oxygen (30 wt%, 55 °C, 0.35 L/min of air, 0.4 molCO2/molTEA, 7.5 mL/min of CO2) and thermal degradation with and without NiNPs (30 wt%, 0.5 molCO2/molTEA, 135 °C). In both degradation experiments, surprisingly, there was no significant difference in TEA degradation in the presence of NiNPs. At high temperature (135 °C), the solution lost 19.2% and 20.3% of the original TEA, with and without NiNPs, respectively. In the presence of oxygen, the solution lost 30.5% and 33.6% of the original TEA, with and without NiNPs, respectively. This indicates that TEA or its mixture with other amines and NiNPs could improve post-combustion CO2 capture.

In order to graft poly(isoprene) on the surface of fulvic acid (FA), fulvic acid-g-poly(isoprene) grafting polymer (FA-g-PI) was synthesized by reversible addition–fragmentation chain transfer polymerization. Because FA-g-PI became more hydrophobic, the static contact angle of FA-g-PI was 67°, which was increased by 37° compared with FA. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis showed that PI was grafted onto the FA. Furthermore, FA-g-PI was used as a modifier to melt blend with PLA to prepare poly(lactic acid)/fulvic acid-g-poly(isoprene) grafting copolymer composites (PLA/FA-g-PI). The mechanical performance results presented that the impact strength, tensile strength and elongation at break of PLA/FA-g-PI (0.3 wt%) reached 18.8 kJ/m 2 , 81.5 MPa and 18.47%, respectively, which were increased by 97.8%, 3.6% and 5.0% compared with PLA. The scanning electron microscopy analysis of impact fracture for PLA/FA-g-PI (0.3 wt%) also clearly showed that PLA/FA-g-PI (0.3 wt%) had the typical toughness fracture morphology feature. The results of differential scanning calorimetry and polarized optical microscope analysis indicated that the addition of FA-g-PI reduced the crystallite size during PLA crystallization. The kinetics of thermo-oxygen degradation by Kissinger method showed that the apparent activation energy of PLA/FA-g-PI (0.3 wt%) composites was increased from 153.73 kJ/mol to 179.17 kJ/mol, which was shown that FA-g-PI improved the thermal stability of PLA. Moreover, the reaction order showed that FA-g-PI had little effect on the PLA thermo-oxygen degradation reaction kinetic order under the air atmosphere.

Beverage industries often discharge large amounts of organic matter with their wastewater. Purification of the effluent is their obligation, but it is nontrivial. Among wastewater components, removal of dissolved organic matter often requires much effort. Therefore, a special effective technique must be considered. Microbubbles (1–100 μm) have several special properties of relevance to wastewater treatment. In this study, the effectiveness of microbubbles for treating and purifying beverage wastewater was evaluated. Orange juice, lactic acid drink, and milk were used as model substrates of dissolved organic matter, and degradation experiments were carried out. Rates of air supply by microbubbles were 0.05% (air/wastewater) min−1. Results indicated that the total organic carbon (TOC) in an experimental vessel containing milk (high nitrogen content) decreased by 93.1% from 11.0 to 0.76 g during a 10-day incubation. The TOC of lactic acid drink (least nitrogen content) decreased by 66.3%, from 15.6 to 5.26 g, and the TOC of orange juice (medium nitrogen content) decreased by 82.7%, from 14.8 to 2.55 g. Large amounts of particulate organic matter floated on the water surface in the milk with microbubbles and were removed easily, while almost no floating materials were observed in the orange juice and lactic acid drink. In contrast, in the macrobubble treatment (diameter 0.1 to 2 mm), only 37.0% of TOC in the milk was removed. Whereas the macrobubble treatments were anaerobic throughout the incubations, the microbubble treatments returned to aerobic conditions quickly, and brought 10 times greater bacterial abundances (>108 cells mL−1). These results suggest that microbubbles are much superior to macrobubbles in supplying oxygen and accelerating the growth of aerobic bacteria, and that wastewater containing more nitrogenous compounds was purified more effectively than that with less nitrogen by microbial degradation and floating separation.

Background: Skinboosters represent the latest category of hyaluronan (HA) hydrogels released for aesthetic purposes. Different from originally developed gels, they are intended for more superficial injections, claiming a skin rejuvenation effect through hydration and possibly prompting biochemical effects in place of the conventional volumetric action. Here, three commercial skinboosters were characterized to unravel the scientific basis for such indication and to compare their performances. Methods: Gels were evaluated for water-soluble/insoluble-HA composition, rheology, hydration, cohesivity, stability and effect, in vitro, on human dermal fibroblasts towards the production of extracellular matrix components. Results: Marked differences in the insoluble-hydrogel amount and in the hydrodynamic parameters for water-soluble-HA chains were evidenced among the gels. Hydration, rigidity and cohesivity also varied over a wide range. Sensitivity to hyaluronidases and Reactive Oxygen Species was demonstrated allowing a stability ranking. Slight differences were found in gels’ ability to prompt elastin expression and in ColIV/ColI ratio. Conclusions. A wide panel of biophysical and biochemical parameters for skinboosters was provided, supporting clinicians in the conscious tuning of their use. Data revealed great variability in gels’ behavior notwithstanding the same clinical indication and unexpected similarities to the volumetric formulations. Data may be useful to improve customization of gel design toward specific uses.

Hypoxia-inducible factors (HIF) belong to the basic helix loop helix–PER ARNT SIM (bHLH-PAS) family of transcription factors that induce metabolic reprogramming under hypoxic condition. The phylogenetic studies of hypoxia-inducible factor-1α (HIF-1α) sequences across different organisms/species may leave a clue on the evolutionary relationships and its probable correlation to tumorigenesis and adaptation to low oxygen environments. In this study, we have aimed at the evolutionary investigation of the protein HIF-1α across different species to decipher their sequence variations/mutations and look into the probable causes and abnormal behaviour of this molecule under exotic conditions. In total, 16 homologous sequences for HIF-1α were retrieved from the National Center for Biotechnology Information. Sequence identity was performed using the Needle program. Multiple aligned sequences were used to construct the phylogeny using the neighbour-joining method. Most of the changes were observed in oxygen-dependent degradation domain and inhibitory domain. Sixteen sequences were clustered into 5 groups. The phylogenetic analysis clearly highlighted the variations that were observed at the sequence level. Comparisons of the HIF-1α sequence among cancer-prone and cancer-resistant animals enable us to find out the probable clues towards potential risk factors in the development of cancer.

Purpose A hypoxia-inducible VEGF expression system with the oxygen-dependent degradation (ODD) domain was constructed and tested to be used in gene therapy for ischemic myocardial disease. Methods Luciferase and VEGF expression vector systems were constructed with or without the ODD domain: pEpo-SV-Luc (or pEpo-SV-VEGF) and pEpo-SV-Luc-ODD (or pEpo-SV-VEGF-ODD). In vitro gene expression efficiency of each vector type was evaluated in HEK 293 cells under both hypoxic and normoxic conditions. The amount of VEGF protein was estimated by ELISA. The VEGF expression vectors with or without the ODD domain were injected into ischemic rat myocardium. Fibrosis, neovascularization, and cardiomyocyte apoptosis were assessed using Masson's trichrome staining, α-smooth muscle actin (α-SMA) immunostaining, and the TUNEL assay, respectively. Results The plasmid vectors containing ODD significantly improved the expression level of VEGF protein in hypoxic conditions. The enhancement of VEGF protein production was attributed to increased protein stability due to oxygen deficiency. In a rat model of myocardial ischemia, the pEpo-SV-VEGF-ODD group exhibited less myocardial fibrosis, higher microvessel density, and less cardiomyocyte apoptosis compared to the control groups (saline and pEpo-SV-VEGF treatments). Conclusion An ODD-mediated VEGF expression system that facilitates VEGF-production under hypoxia may be useful in the treatment of ischemic heart disease.

Hypoxia-inducible factor-1 (HIF-1) plays an important role in malignant tumor progression and in the development of resistance to radiotherapy. We designed a novel fusion protein (PTD-ODD-SAV [POS]) consisting of a protein transduction domain (PTD), streptavidin (SAV), and a portion of the oxygen-dependent degradation domain (ODD) of HIF-1alpha that confers the same oxygen-dependent regulation as HIF-1alpha on POS. (3-(123/125)I-iodobenzoyl)norbiotinamide ((123/125)I-IBB) was conjugated to the SAV moiety of POS to synthesize (123/125)I-IBB-labeled POS ((123/125)I-IPOS). The purpose of this study was to evaluate the feasibility of (123)I-IPOS as an imaging probe for HIF-1-active tumor hypoxia. After a 24-h incubation of (125)I-IPOS with various tumor cell lines under either normoxic (20% O(2)) or hypoxic (0.1% O(2)) conditions, the intracellular radioactivity was investigated. Then, the biodistribution of (123/125)I-IPOS was examined with tumor-implanted mice, and an in vivo imaging study was performed. The tumoral accumulation of (125)I-IPOS was compared with HIF-1 activity using the mice carrying tumors with the HIF-1-dependent luciferase reporter gene. Furthermore, the intratumoral localization of (125)I-IPOS was examined by the autoradiographic study, and then the same slide was subjected to immunostaining for pimonidazole, which is the hypoxic marker. The ratios of radioactivity in hypoxic cells to that in normoxic cells were more than 2. These results indicate incorporation of (125)I-IPOS into these cells and degradation of (125)I-IPOS by normoxic tumor cells. In the biodistribution study, (125)I-IPOS accumulated in the tumor (1.4 +/- 0.3 percentage injected dose per gram) 24 h after administration. At that time, (125)I-IPOS showed high tumor-to-blood and tumor-to-muscle ratios (5.1 +/- 0.3 and 14.0 +/- 3.9, respectively). The tumors were clearly visualized by in vivo imaging 24 h after (123)I-IPOS injection (tumor-to-muscle ratio was 9.6). The tumoral accumulation of (125)I-IPOS correlated with HIF-1 activity (R = 0.71, P < 0.05), and its intratumoral distribution coincided with the hypoxic regions. (123)I-IPOS is a potential probe for the imaging of HIF-1 activity in tumors. Given the role of HIF-1 in tumor biology, its detection may be considered an indicator of aggressive cancer phenotypes.

Purpose Hypoxia-inducible factor-1 (HIF-1) plays an important role in malignant tumour progression. For the imaging of HIF-1-active tumours, we previously developed a protein, POS, which is effectively delivered to and selectively stabilized in HIF-1-active cells, and a radioiodinated biotin derivative, (3- 123 I-iodobenzoyl)norbiotinamide ( 123 I-IBB), which can bind to the streptavidin moiety of POS. In this study, we aimed to investigate the feasibility of the pretargeting method using POS and 123 I-IBB for rapid imaging of HIF-1-active tumours. Methods Tumour-implanted mice were pretargeted with POS. After 24 h, 125 I-IBB was administered and subsequently, the biodistribution of radioactivity was investigated at several time points. In vivo planar imaging, comparison between 125 I-IBB accumulation and HIF-1 transcriptional activity, and autoradiography were performed at 6 h after the administration of 125 I-IBB. The same sections that were used in autoradiographic analysis were subjected to HIF-1α immunohistochemistry. Results 125 I-IBB accumulation was observed in tumours of mice pretargeted with POS (1.6%ID/g at 6 h). This result is comparable to the data derived from 125 I-IBB-conjugated POS-treated mice (1.4%ID/g at 24 h). In vivo planar imaging provided clear tumour images. The tumoral accumulation of 125 I-IBB significantly correlated with HIF-1-dependent luciferase bioluminescence ( R =0.84, p <0.01). The intratumoral distribution of 125 I-IBB was heterogeneous and was significantly correlated with HIF-1α-positive regions ( R =0.58, p <0.0001). Conclusion POS pretargeting with 123 I-IBB is a useful technique in the rapid imaging and detection of HIF-1-active regions in tumours.

Purpose We aimed to develop a radiolabeled peptide probe for the imaging of hypoxia-inducible factor-1 (HIF-1)-active tumors. Procedures We synthesized the peptide probes that contain or lack an essential sequence of the oxygen-dependent degradation of HIF-1α in proteasomes ( 123/125 I-DKOP30 or 125 I-mDKOP, respectively). The degradation of probes was evaluated in vitro using cell lysates containing proteasomes. In vivo biodistribution study, planar imaging, autoradiography, and comparison between probe accumulation and HIF-1 transcriptional activity were also performed. Results The 125 I-DKOP30 underwent degradation in a proteasome-dependent manner, while 125 I-mDKOP was not degraded. Biodistribution analysis showed 125 I-DKOP30 accumulation in tumors. The tumors were clearly visualized by in vivo imaging, and intratumoral distribution of 125 I-DKOP30 coincided with the HIF-1α-positive hypoxic regions. Tumoral accumulation of 125 I-DKOP30 was significantly correlated with HIF-1-dependent luciferase bioluminescence, while that of 125 I-mDKOP was not. Conclusion 123 I-DKOP30 is a useful peptide probe for the imaging of HIF-1-active tumors.