YREE determination in seawater. Standardization and validation of a new method based on preconcentration techniques

The most interesting attraction of using rare-earth elements and yttrium (YREE) to address geochemical and marine chemical problems consists of their chemical coherence as group of trace elements. These characters allow YREE compositions of rocks and minerals to be extensively used in studies of provenance, petrogenesis and chemical evolution of the geological materials (1). Similarly, YREE compositions in the hydrosphere were used in studies of coagulation, particle-solution reactions and oceanic circulation of water masses (2-4). Unfortunately, very low concentrations of YREE (ng l-1 or sub-ng l-1) associated to high ionic strength of seawater always represented the main difficulty to analyse dissolved YREE in marine environment. The first geochemical investigations of YREE contents in seawater were carried out using neutron activation and isotope dilution mass spectrometry that were almost entirely replaced by inductively coupled plasma supplemented by mass spectrometry (ICP-MS) in recent years. This technique offers many advantages including simultaneous analysis of all the elements of series and their quantitative determination with detection limits of the order of ng l-1 if associated to preconcentration techniques (5). To perform ultra-trace YREE analyses in seawater, we developed a preconcentration method based on CHELEX-100 iminodiacetate resin followed by ICP-MS determination (Ref). In this study the YREE behaviour was quantitatively investigated during interactions with ion chelating resin and estimation of composed measurement uncertainty associated to measurements was evaluated with a rigorous metrological approach based on method validation and quality control of YREE data. These goals were achieved using synthetic seawater where YREE had concentrations as occurring in natural seawater samples. Under these conditions good recovery were obtained along the YREE series, ranging from 75%-85% and 90%-100% for heavy REE and Y and light REE, respectively. Composed measurement uncertainty was expressed in terms of precision, recovery uncertainties, reference material uncertainty and instrumental calibration uncertainty. The obtained results were critically discussed on the basis of the different contributions and confirm the quadrupole ICP-MS technique as highly sensitive to determine very low YREE concentrations. REFERENCES 1. S. R. Taylor, S.M. McLennan, The Continental Crust: its Composition and Evolution. Blackwell Scientific Publications, Oxford, 1985). 2. G.J. Piepgras, G.J. Wasserburg, Science 217 (1982) 207. 3. J. Zhang, Y. Nozaki, Geochim. Cosmochim. Acta 60 (1996) 4631. 4. R.H. Byrne, E. Sholkovitz, In: Gschneidner, J.K.A., Eyring, (Eds.), Handbook on the Physics and Chemistry of Rare Earths. Elsevier, New York, (1996) 498-593. 5. P. M\uf6ller, P. Dulski P., J. Luck, Spectrochim. Acta, 47B, 1379

Population genetic structure and milk production traits in Girgentana goat breed

The aim of this work was to evaluate the genetic status of the Girgentana goat, an endangered breed from Sicily (Italy), using microsatellite markers. Furthermore, as the main purpose of the Girgentana breed is milk production, quantitative milk traits were investigated, including fatty acid profile. Molecular data from CSN1S1, CSN2, CSN1S2, and CSN3 casein genes were also used to infer haplotypes. A total of 264 individuals were collected. Samples of Maltese (n 64 41) and Derivata di Siria (n 64 33) goat breeds were also used to understand the genetic relationship among breeds. Test-day records for milk production were collected to determine daily milk yield, fat, protein, casein, lactose, and somatic cell count. Individual milk samples were also collected for fatty acid extraction. Wright's statistics, gene flow, Nei genetic distance, factorial correspondence analysis, and Bayesian assignment test showed the existence of genetic variability and differentiation among breeds. The AMOVA results indicated that 89.96% of the total variance was partitioned within populations. The Girgentana breed appears to have a subdivided population, and has not experienced a recent bottleneck. A high variability in milk yield was observed. Mean morning milk yield was 1448 \ub1 404 g, with 4.30 \ub1 0.87% and 3.72 \ub1 0.44% of fat and protein percentages, respectively. The average somatic cell count found in Girgentana goat milk was higher than the threshold of 1 500000 cells/mL advised in Europe for fresh milk. Gross milk and fatty acid composition were similar to that reported in the literature for other local goat breeds

Quantitative determination of casein genetic variants in goat milk: Application in Girgentana dairy goat breed

The study was conducted to develop a high-performance liquid chromatographic (HPLC) method to quantify casein genetic variants (s2-, β-, and κ-casein) in milk of homozygous individuals of Girgentana goat breed. For calibration experiments, pure genetic variants were extracted from individual milk samples of animals with known genotypes. The described HPLC approach was precise, accurate and highly suitable for quantification of goat casein genetic variants of homozygous individuals. The amount of each casein per allele was: s2-casein A=2.9 ± 0.8 g/L and F=1.8 ± 0.4 g/L; β-casein C=3.0 ± 0.8 g/L and C1=2.0 ± 0.7 g/L and κ-casein A=1.6 ± 0.3 g/L and B=1.1 ± 0.2 g/L. A good correlation was found between the quantities of s2-casein genetic variants A and F, and β-casein C and C1 with other previously described method. The main important result was obtained for κ-casein because, till now, no data were available on quantification of single genetic variants for this protein

Autoimmune complications in chronic lymphocytic leukemia in the era of targeted drugs

Autoimmune phenomena are frequently observed in patients with chronic lymphocytic leukemia (CLL) and are mainly attributable to underlying dysfunctions of the immune system. Autoimmune cytopenias (AIC) affect 4–7% of patients with CLL and mainly consist of autoimmune hemolytic anemia and immune thrombocytopenia. Although less common, non-hematological autoimmune manifestations have also been reported. Treatment of CLL associated AIC should be primarily directed against the autoimmune phenomenon, and CLL specific therapy should be reserved to refractory cases or patients with additional signs of disease progression. New targeted drugs (ibrutinib, idelalisib and venetoclax) recently entered the therapeutic armamentarium of CLL, showing excellent results in terms of efficacy and became an alternative option to standard chemoimmunotherapy for the management of CLL associated AIC. However, the possible role of these drugs in inducing or exacerbating autoimmune phenomena still needs to be elucidated. In this article, we review currently available data concerning autoimmune phenomena in patients with CLL, particularly focusing on patients treated with ibrutinib, idelalisib, or venetoclax, and we discuss the possible role of these agents in the management of AIC

HSV-1 Glycoprotein D and Its Surface Receptors: Evaluation of Protein–Protein Interaction and Targeting by Triazole-Based Compounds through In Silico Approaches

Protein–protein interactions (PPI) represent attractive targets for drug design. Thus, aiming at a deeper insight into the HSV-1 envelope glycoprotein D (gD), protein–protein docking and dynamic simulations of gD-HVEM and gD-Nectin-1 complexes were performed. The most stable complexes and the pivotal key residues useful for gD to anchor human receptors were identified and used as starting points for a structure-based virtual screening on a library of both synthetic and designed 1,2,3-triazole-based compounds. Their binding properties versus gD interface with HVEM and Nectin-1 along with their structure-activity relationships (SARs) were evaluated. Four [1,2,3]triazolo[4,5-b]pyridines were identified as potential HSV-1 gD inhibitors, for their good theoretical affinity towards all conformations of HSV-1 gD. Overall, this study suggests promising basis for the design of new antiviral agents targeting gD as a valuable strategy to prevent viral attachment and penetration into the host cell

Dual inhibitory action of trazodone on dorsal raphe serotonergic neurons through 5-HT1A receptor partial agonism and α1-adrenoceptor antagonism

Trazodone is an antidepressant drug with considerable affinity for 5-HT1A receptors and α1-adrenoceptors for which the drug is competitive agonist and antagonist, respectively. In this study, we used cell-attached or whole-cell patch-clamp recordings to characterize the effects of trazodone at somatodendritic 5-HT1A receptors (5-HT1AARs) and α1-adrenoceptors of serotonergic neurons in rodent dorsal raphe slices. To reveal the effects of trazodone at α1-adrenoceptors, the baseline firing of 5-HT neurons was facilitated by applying the selective α1-adrenoceptor agonist phenylephrine at various concentrations. In the absence of phenylephrine, trazodone (1-10 μM) concentration-dependently silenced neurons through activation of 5-HT1AARs. The effect was fully antagonized by the selective 5-HT1A receptor antagonist Way-100635. With 5-HT1A receptors blocked by Way-100635, trazodone (1-10 μM) concentration-dependently inhibited neuron firing facilitated by 1 μM phenylephrine. Parallel rightward shift of dose-response curves for trazodone recorded in higher phenylephrine concentrations (10-100 μM) indicated competitive antagonism at α1-adrenoceptors. Both effects of trazodone were also observed in slices from Tph2-/- mice that lack synthesis of brain serotonin, showing that the activation of 5-HT1AARs was not mediated by endogenous serotonin. In whole-cell recordings, trazodone activated 5-HT1AAR-coupled G protein-activated inwardly-rectifying (GIRK) channel conductance with weak partial agonist efficacy (~35%) compared to that of the full agonist 5-CT. Collectively our data show that trazodone, at concentrations relevant to its clinical effects, exerts weak partial agonism at 5-HT1AARs and disfacilitation of firing through α1-adrenoceptor antagonism. These two actions converge in inhibiting dorsal raphe serotonergic neuron activity, albeit with varying contribution depending on the intensity of α1-adrenoceptor stimulation

Evaluation of Fused Pyrrolothiazole Systems as Correctors of Mutant CFTR Protein

Cystic fibrosis (CF) is a genetic disease caused by mutations that impair the function of the CFTR chloride channel. The most frequent mutation, F508del, causes misfolding and premature degradation of CFTR protein. This defect can be overcome with pharmacological agents named "correctors". So far, at least three different classes of correctors have been identified based on the additive/synergistic effects that are obtained when compounds of different classes are combined together. The development of class 2 correctors has lagged behind that of compounds belonging to the other classes. It was shown that the efficacy of the prototypical class 2 corrector, the bithiazole corr-4a, could be improved by generating conformationally-locked bithiazoles. In the present study, we investigated the effect of tricyclic pyrrolothiazoles as analogues of constrained bithiazoles. Thirty-five compounds were tested using the functional assay based on the halide-sensitive yellow fluorescent protein (HS-YFP) that measured CFTR activity. One compound, having a six atom carbocyle central ring in the tricyclic pyrrolothiazole system and bearing a pivalamide group at the thiazole moiety and a 5-chloro-2-methoxyphenyl carboxamide at the pyrrole ring, significantly increased F508del-CFTR activity. This compound could lead to the synthesis of a novel class of CFTR correctors