A Simple and Adaptive Methodology to Use a Commercial Solvent Extraction Microsystem as Screening Tool: Validation with the U-TBP Chemical System

The solvent extraction of a U (VI) present at several g.L^?1 from the aqueous phase [HNO₃] = 3 M to the organic one (30% TBP) involves a change of the viscosity of the two phases during the extraction process in microsystem. This shifts the position of the interface between the two phases and then affects the quality of the separation at the outlet of the microsystem. The aim of this study is to present a simple method to stabilize the quality of the separation by controlling the interface position during solvent extraction in microsystem. First, a study at low concentration is operated in order to set flow rates and contact time that allow optimal parallel flows and mass transfer. Second, the influence of the high grade concentration (up to 140 g.L^?1) of solute on the flows and extraction yield is studied.     

Biomimetic protein‐based elastomeric hydrogels for biomedical applications

In recent years, protein‐based elastomeric hydrogels have gained increased research interest in biomedical applications for their remarkable self‐assembly behaviour, tunable 3D porous structure, high resilience (elasticity), fatigue lifetime (durability), water uptake, excellent biocompatibility and biological activity. The proteins and polypeptides can be derived naturally (animal or insect sources) or by recombinant (bacterial expression) routes and can be crosslinked via physical or chemical approaches to obtain elastomeric hydrogels. Here we review and present the recent accomplishments in the synthesis, fabrication and biomedical applications of protein‐based elastomeric hydrogels such as elastin, resilin, flagelliform spider silk and their derivatives. © 2013 Society of Chemical Industry     

Near-Infrared Imaging Spectroscopy as a Tool to Discriminate Two Cryptic Tetramorium Ant Species

Correct species identification is a precondition for many ecological studies. Morphologically highly similar, i.e., cryptic, species are an important component of biodiversity but particularly difficult to discriminate and therefore understudied ecologically. To find new methods for their rapid identification, thus, is important. The cuticle's chemical signature of insects often is unique for species. Near-infrared spectroscopy (NIRS) can capture such signatures. Imaging NIRS facilitates precise positioning of the measurement area on biological objects and high-resolution spatial capturing. Here, we tested the applicability of imaging NIRS to the discrimination of cryptic species by using the ants Tetramorium caespitum and T. impurum. The classification success of Partial Least Squares Regression was 98.8%. Principal Component Analysis grouped spectra of some T. impurum individuals with T. caespitum. Combined with molecular-genetic and morphological evidence, this result enabled us to pose testable hypotheses about the biology of these species. We conclude that discrimination of T. caespitum and T. impurum with imaging NIRS is possible, promising that imaging NIRS could become a time- and cost-efficient tool for the reliable discrimination of cryptic species. This and the direct facilitation of potential biological insight beyond species identification underscore the value of imaging NIRS to ecology.     

Biochemical and molecular characterization of polymorphisms of αs1-casein in Sudanese camel (Camelus dromedarius) milk

This work was designed to detect occurrence of biochemical polymorphism of α_s1-casein in two ecotypes of Sudanese camel (Camelus dromedarius) and to characterize these variants on molecular level. Milk samples were screened for α_s1-casein variability by isoelectric focusing, using skimmed milk, as well as isolated α_s1-casein. Two protein patterns, named α_s1-casein A and C, were identified, whereas the major allele A revealed frequencies of 0.8214 and 0.8615 in the two ecotypes. CSN1S1*A and CSN1S1*C are both characterized by missing of exon 16 on mRNA-level compared with the previously described CSN1S1*B. However, the sequence of exon 16 occurs on DNA-level in both. Therefore, this exon seems to be skipped out during mRNA-processing. Furthermore, CSN1S1*C shows a single G > T nucleotide substitution in exon 5, leading to a non-synonymous amino acid exchange (p.Glu30 > Asp30; GenBank ID: JF429138). A polymerase chain reaction-restriction fragment length polymorphism-method was established as a DNA-based test for this nucleotide substitution.     

Preconcentration and determination of Cu (II) from aqueous samples using functionalized sawdust and comparison with synthetic functionalized sorbents

The efficiency of indigenous functionalized sorbent (sawdust functionalized with polyaniline) was compared with synthetic functionalized sorbents (Dowex functionalized with 8-hydroxyquinoline (Dowex-8HQ) and α-nitroso-β-naphthol (Dowex-αNβN)) for preconcentration and determination of Cu (II) from aqueous samples. The synthetic functionalized sorbents and indigenous functionalized sorbent were characterized using FTIR. Different parameters like pH, equilibration time and sample volume were investigated for maximum sorption of Cu (II). Isotherm studies showed that the sorption data fitted well into Langmuir isotherm for the sawdust functionalized with polyaniline. Freundlich isotherm was followed for Dowex-8HQ and Dowex-αNβN. Four types of kinetic equations were applied to the data, and it was observed that sorption of Cu (II) followed second-order kinetics. Thermodynamically, the sorption of Cu (II) on these three sorbents was found to be exothermic and spontaneous. For maximum recovery of Cu (II) from loaded sorbents, different parameters like shaking time, eluent type, concentration and volume were investigated, and 89% Cu (II) was recovered from loaded sawdust functionalized with polyaniline and Dowex-8HQ. The interference studies showed the selectivity of sawdust functionalized with polyaniline for Cu (II) in comparison to synthetic functionalized sorbents. Thus, Cu (II) can be easily removed from aqueous samples in the presence of foreign ions.     

Preconcentration and Determination of Pb (II) in Aqueous Samples using Functionalized Dowex 1X8

Synthetic resin Dowex 1X8 was functionalized with α-Nitroso β-Naphthol (Dowex-αNβN) and with 8-Hydroxy Quinoline (Dowex-8HQ) to form chelating resin. The resultant chelating resins were characterized using scanning electron microscopy (SEM), thermo gravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). The efficiency of these resins for the removal/preconcentration of Pb (II) from aqueous samples was evaluated. Optimum conditions of pH, time of equilibrium, and sample volume were investigated for maximum retention of Pb (II) from aqueous solutions. At optimum conditions, 100% adsorption was observed for the functionalized resins. Both Freundlich and Langmuir isotherms were applied to the adsorption data and it was observed that data fits well to Langmuir isotherm. Various parameters such as shaking time, type, and concentration of eluents were investigated for the recovery of Pb (II) from the chelating resins. For Dowex-αNβN and Dowex-8HQ, 100% recovery with a preconcentration factor of 100 was achieved with 0.5 and 2 M HCl, respectively. The selectivity and specificity of the functionalized resins was also evaluated by studying the effect of various foreign ions and the results have been compared with the unmodified Dowex.     

Enzalutamide Enhances PSMA Expression of PSMA-Low Prostate Cancer

Prostate-specific membrane antigen (PSMA)-directed radioligand therapy (RLT) prolongs overall survival in men with metastatic castration-resistant prostate cancer (mCRPC). However, men with low PSMA expression are excluded from RLT. We explored the effect of androgen receptor blockade with enzalutamide on PSMA expression. Assessment of PSMA and androgen receptor (AR) expression on the human PC cell lines 22Rv1, C4-2, and LNCaP by immunohistochemistry and flow cytometry revealed low (22Rv1) and high (C4-2 and LNCaP) PSMA expression, and high, comparable AR positivity. Treatment with enzalutamide increased PSMA levels in 22Rv1, C4-2, and LNCaP (2.2/2.3/2.6-fold, p = 0.0005/0.03/0.046) after one week compared to DMSO-treated controls as assessed by flow cytometry. NOD/Scid mice bearing 22Rv1 tumors were treated with enzalutamide for two weeks. Positron emission tomography/computed tomography (PET/CT) demonstrated higher tumor uptake of ⁶⁸Ga-PSMA after enzalutamide treatment (p = 0.004). Similarly, a clinical case with low baseline PSMA avidity demonstrated increased uptake of ⁶⁸Ga-PSMA after enzalutamide on PET/CT and post-therapeutic ¹⁷⁷Lu-PSMA scintigraphy in a patient with mCRPC. Enzalutamide induced PSMA expression in the 22Rv1 xenograft model and in an mCRPC patient, both with low baseline tumoral PSMA levels. Therefore, enzalutamide pre-treatment might render patients with low PSMA expression eligible for ¹⁷⁷Lu-PSMA RLT.     

Adsorption of arsenic on polyaluminum granulate

The kinetics and efficiencies of arsenite and arsenate removal from water were evaluated using polyaluminum granulates (PAG) with high content of aluminum nanoclusters. PAG was characterized to be meso- and macroporous, with a specific surface area of 35 ± 1 m(2) g(-1). Adsorption experiments were conducted at pH 7.5 in deionized water and synthetic water with composition of As-contaminated groundwater in the Pannonian Basin. As(III) and As(V) sorption was best described by the Freundlich and Langmuir isotherm, respectively, with a maximum As(V) uptake capacity of ~200 μmol g(-1) in synthetic water. While As(III) removal reached equilibrium within 40 h, As(V) was removed almost entirely within 20 h. Micro X-ray fluorescence and electron microscopy revealed that As(III) was distributed uniformly within the grain, whereas As(V) diffused up to 81 μm into PAG. The results imply that As(V) is adsorbed 3 times faster while being transported 10(5) times slower than As(III) in Al hydroxide materials.