14 research outputs found
Removal of phosphate from aqueous solutions by adsorption onto Ca(OH)2 treated natural clinoptilolite
Phosphorus (P) recovery from wastewater is of great interest especially when the loaded adsorbent can be used in the agriculture as slow-release fertilizer. The application depends on environmental concerns related to the chemical modification of the adsorbent and the release of toxic compounds from the loaded material to the soil or the water during adsorption. The present work focused on the phosphate (PO4-P) removal from aqueous solutions under low P concentrations (0.5–10mg/L) by using Ca(OH)2-pretreated natural zeolite (CaT-Z). As activation agent, Ca(OH)2 presents benefits in terms of pretreatment costs and environmental impact of the applied adsorbent. The pretreatment of natural zeolite (clinoptilolite) with 0.25mol/L Ca(OH)2 led to an increase of P removal from 1.7 to 97.6% at initial P concentration of 10mg/L, pH 7 and 298K. Low residual concentrations of 81–238μg P/L were achieved at 298K rendering CaT-Z a promising sorbent for tertiary wastewater treatment. At 200mg P/L, the adsorption capacity was 7.57mg P/g CaT-Z. The P removal efficiency was pH-independent suggesting a beneficial use of CaT-Z under acidic and alkaline conditions. Adsorption was found to be an endothermic and slow process reaching equilibrium after 120h, whereas the half of the PO4-P was adsorbed in the first 8h. The applied kinetic models showed that both film and intraparticle diffusion contributed to phosphate removal. Phosphate sorption decreased in the presence of the anionic surfactant SDS, Fe2+, HCO3−, acetate and citrate anion. The predominant mechanisms of ligand exchange and Ca-P surface precipitation were confirmed by the IR-ATR and SEM-EDS analyses, respectively
A Novel Metal-Based Imaging Probe for Targeted Dual-Modality SPECT/MR Imaging of Angiogenesis
Superparamagnetic iron oxide nanoparticles with well-integrated multimodality imaging properties have generated increasing research interest in the past decade, especially when it comes to the targeted imaging of tumors. Bevacizumab (BCZM) on the other hand is a well-known and widely applied monoclonal antibody recognizing VEGF-A, which is overexpressed in angiogenesis. The aim of this proof-of-concept study was to develop a dual-modality nanoplatform for in vivo targeted single photon computed emission tomography (SPECT) and magnetic resonance imaging (MRI) of tumor vascularization. Iron oxide nanoparticles (IONPs) have been coated with dimercaptosuccinic acid (DMSA), for consequent functionalization with the monoclonal antibody BCZM radiolabeled with 99mTc, via well-developed surface engineering. The IONPs were characterized based on their size distribution, hydrodynamic diameter and magnetic properties. In vitro cytotoxicity studies showed that our nanoconstruct does not cause toxic effects in normal and cancer cells. Fe3O4-DMSA-SMCC-BCZM-99mTc were successfully prepared at high radiochemical purity (>92%) and their stability in human serum and in PBS were demonstrated. In vitro cell binding studies showed the ability of the Fe3O4-DMSA-SMCC-BCZM-99mTc to bind to the VEGF-165 isoform overexpressed on M-165 tumor cells. The ex vivo biodistribution studies in M165 tumor-bearing SCID mice showed high uptake in liver, spleen, kidney and lungs. The Fe3O4-DMSA-SMCC-BCZM-99mTc demonstrated quick tumor accumulation starting at 8.9 ± 1.88%ID/g at 2 h p.i., slightly increasing at 4 h p.i. (16.21 ± 2.56%ID/g) and then decreasing at 24 h p.i. (6.01 ± 1.69%ID/g). The tumor-to-blood ratio reached a maximum at 24 h p.i. (~7), which is also the case for the tumor-to-muscle ratio (~18). Initial pilot imaging studies on an experimental gamma-camera and a clinical MR camera prove our hypothesis and demonstrate the potential of Fe3O4-DMSA-SMCC-BCZM-99mTc for targeted dual-modality imaging. Our findings indicate that Fe3O4-DMSA-SMCC-BCZM-99mTc IONPs could serve as an important diagnostic tool for biomedical imaging as well as a promising candidate for future theranostic applications in cancer
An Adaptive Fuzzy Logic System for the Compensation of Nonlinear Distortion in Wireless Power Amplifiers
Computational intelligent systems are becoming an increasingly attractive solution for power amplifier (PA) behavioural modelling, due to their excellent approximation capability. This paper utilizes an adaptive fuzzy logic system (AFLS) for the modelling of the highly nonlinear MIMIX CFH2162-P3 PA. Moreover, PA’s inverse model based also on AFLS has been developed in order to act as a pre-distorter unit. Driving an LTE 1.4 MHz 64 QAM signal at 880 MHz as centre frequency at PA’s input, very good modelling performance was achieved, for both PA’s forward and inverse dynamics. A comparative study of AFLS and neural networks (NN) has been carried out to establish AFLS as an effective, robust, and easy-to-implement baseband model, which is suitable for inverse modelling of PAs and capable to be used as an effective digital pre-distorter. Pre-distortion system based on AFLS, achieved distortion suppression of 84.2%, compared to the 48.4% gained using the NN-based equivalent schem
A Novel Metal-Based Imaging Probe for Targeted Dual-Modality SPECT/MR Imaging of Angiogenesis
Superparamagnetic iron oxide nanoparticles with well-integrated multimodality imaging properties have generated increasing research interest in the past decade, especially when it comes to the targeted imaging of tumors. Bevacizumab (BCZM) on the other hand is a well-known and widely applied monoclonal antibody recognizing VEGF-A, which is overexpressed in angiogenesis. The aim of this proof-of-concept study was to develop a dual-modality nanoplatform for in vivo targeted single photon computed emission tomography (SPECT) and magnetic resonance imaging (MRI) of tumor vascularization. Iron oxide nanoparticles (IONPs) have been coated with dimercaptosuccinic acid (DMSA), for consequent functionalization with the monoclonal antibody BCZM radiolabeled with Tc-99m, via well-developed surface engineering. The IONPs were characterized based on their size distribution, hydrodynamic diameter and magnetic properties. In vitro cytotoxicity studies showed that our nanoconstruct does not cause toxic effects in normal and cancer cells. Fe3O4-DMSA-SMCC-BCZM-Tc-99m were successfully prepared at high radiochemical purity (> 92%) and their stability in human serum and in PBS were demonstrated. In vitro cell binding studies showed the ability of the Fe3O4-DMSA-SMCC-BCZM-Tc-99m to bind to the VEGF-165 isoform overexpressed on M-165 tumor cells. The ex vivo biodistribution studies in M165 tumor-bearing SCID mice showed high uptake in liver, spleen, kidney and lungs. The Fe3O4-DMSA-SMCC-BCZM-Tc-99m demonstrated quick tumor accumulation starting at 8.9 +/- 1.88% ID/g at 2 h p.i., slightly increasing at 4 h p.i. (16.21 +/- 2.56% ID/g) and then decreasing at 24 h p.i. (6.01 +/- 1.69% ID/g). The tumor-to-blood ratio reached a maximum at 24 h p.i. (similar to 7), which is also the case for the tumor-to- muscle ratio (similar to 18). Initial pilot imaging studies on an experimental gamma-camera and a clinical MR camera prove our hypothesis and demonstrate the potential of Fe3O4-DMSA-SMCC-BCZM-Tc-99m for targeted dual-modality imaging. Our findings indicate that Fe3O4-DMSA-SMCC-BCZM-Tc-99m IONPs could serve as an important diagnostic tool for biomedical imaging as well as a promising candidate for future theranostic applications in cancer.Open access journal.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Innovative multimodal DOTA/NODA nanoparticles for MRI and PET imaging for tumor detection
International audienc
Prognostic Significance of Serum Inflammatory Response Markers in Newly Diagnosed Non-Small Cell Lung Cancer before Chemoirradiation
Purpose. To identify whether the serum’s baseline C-reactive protein
(CRP) and albumin (Alb) levels related to clinicopathological parameters
and overall survival (OS) in non-small cell lung cancer (NSCLC).
Methods. In total, 100 consecutive patients (mean age = 68.38 +/- 10.85
years) that underwent chemoradiotherapy were studied. Measurements of
CRP and Alb were performed before any treatment. Results. Serum CRP
levels were significantly associated with histological grade (P <
0.001), TNM stage (P < 0.001), PS (P = 0.009), and Alb (P < 0.001).
Additionally CRP and Alb levels were found significantly associated with
overall survival in univariate analysis (log-rank test, P < 0.001 and P
= 0.002, resp.) and CRP remained significant after controlling for age,
alcohol, performance status, and TNM stage, whereas albumin showed a
borderline effect on the hazard rate (P = 0.052). Conclusions. CRP and
Alb are both promising biomarkers in identification of NSCLC patients
with poor prognosis and form a possible target for intensifying their
therapies
Synthesis and Characterization of <i>fac</i>-[M(CO)<sub>3</sub>(P)(OO)] and <i>cis-trans</i>-[M(CO)<sub>2</sub>(P)<sub>2</sub>(OO)] Complexes (M = Re, <sup>99m</sup>Tc) with Acetylacetone and Curcumin as OO Donor Bidentate Ligands
The
synthesis and characterization of neutral mixed ligand complexes <i>fac-</i>[M(CO)<sub>3</sub>(P)(OO)] and <i>cis-trans</i>-[M(CO)<sub>2</sub>(P)<sub>2</sub>(OO)] (M = Re, <sup>99m</sup>Tc),
with deprotonated acetylacetone or curcumin as the OO donor bidentate
ligands and a phosphine (triphenylphosphine or methyldiphenylphosphine)
as the monodentate P ligand, is described. The complexes were synthesized
through the corresponding <i>fac-</i>[M(CO)<sub>3</sub>(H<sub>2</sub>O)(OO)] (M = Re, <sup>99m</sup>Tc) intermediate aqua complex.
In the presence of phosphine, replacement of the H<sub>2</sub>O molecule
of the intermediate complex at room temperature generates the neutral
tricarbonyl monophosphine <i>fac</i>-[Re(CO)<sub>3</sub>(P)(OO)] complex, while under reflux conditions further replacement
of the trans to the phosphine carbonyl generates the new stable dicarbonyl
bisphosphine complex <i>cis-trans</i>-[Re(CO)<sub>2</sub>(P)<sub>2</sub>(OO)]. The Re complexes were fully characterized by
elemental analysis, spectroscopic methods, and X-ray crystallography
showing a distorted octahedral geometry around Re. Both the monophosphine
and the bisphosphine complexes of curcumin show selective binding
to β-amyloid plaques of Alzheimer’s disease. At the <sup>99m</sup>Tc tracer level, the same type of complexes, <i>fac</i>-[<sup>99m</sup>Tc(CO)<sub>3</sub>(P)(OO)] and <i>cis-trans</i>-[<sup>99m</sup>Tc(CO)<sub>2</sub>(P)<sub>2</sub>(OO)], are formed
introducing new donor combinations for <sup>99m</sup>Tc(I). Overall,
β-diketonate and phosphine constitute a versatile ligand combination
for Re(I) and <sup>99m</sup>Tc(I), and the successful employment of
the multipotent curcumin as β-diketone provides a solid example
of the pharmacological potential of this system
Synthesis and Characterization of <i>fac</i>-[M(CO)<sub>3</sub>(P)(OO)] and <i>cis-trans</i>-[M(CO)<sub>2</sub>(P)<sub>2</sub>(OO)] Complexes (M = Re, <sup>99m</sup>Tc) with Acetylacetone and Curcumin as OO Donor Bidentate Ligands
The
synthesis and characterization of neutral mixed ligand complexes <i>fac-</i>[M(CO)<sub>3</sub>(P)(OO)] and <i>cis-trans</i>-[M(CO)<sub>2</sub>(P)<sub>2</sub>(OO)] (M = Re, <sup>99m</sup>Tc),
with deprotonated acetylacetone or curcumin as the OO donor bidentate
ligands and a phosphine (triphenylphosphine or methyldiphenylphosphine)
as the monodentate P ligand, is described. The complexes were synthesized
through the corresponding <i>fac-</i>[M(CO)<sub>3</sub>(H<sub>2</sub>O)(OO)] (M = Re, <sup>99m</sup>Tc) intermediate aqua complex.
In the presence of phosphine, replacement of the H<sub>2</sub>O molecule
of the intermediate complex at room temperature generates the neutral
tricarbonyl monophosphine <i>fac</i>-[Re(CO)<sub>3</sub>(P)(OO)] complex, while under reflux conditions further replacement
of the trans to the phosphine carbonyl generates the new stable dicarbonyl
bisphosphine complex <i>cis-trans</i>-[Re(CO)<sub>2</sub>(P)<sub>2</sub>(OO)]. The Re complexes were fully characterized by
elemental analysis, spectroscopic methods, and X-ray crystallography
showing a distorted octahedral geometry around Re. Both the monophosphine
and the bisphosphine complexes of curcumin show selective binding
to β-amyloid plaques of Alzheimer’s disease. At the <sup>99m</sup>Tc tracer level, the same type of complexes, <i>fac</i>-[<sup>99m</sup>Tc(CO)<sub>3</sub>(P)(OO)] and <i>cis-trans</i>-[<sup>99m</sup>Tc(CO)<sub>2</sub>(P)<sub>2</sub>(OO)], are formed
introducing new donor combinations for <sup>99m</sup>Tc(I). Overall,
β-diketonate and phosphine constitute a versatile ligand combination
for Re(I) and <sup>99m</sup>Tc(I), and the successful employment of
the multipotent curcumin as β-diketone provides a solid example
of the pharmacological potential of this system