A surface acoustic wave sensor functionalized with a polypyrrole molecularly imprinted polymer for selective dopamine detection

A surface acoustic wave sensor operating at 104 MHz and functionalized with a polypyrrole molecularly imprinted polymer has been designed for selective detection of dopamine (DA). Optimization of pyrrole/DA ratio, polymerization and immersion times permitted to obtain a highly selective sensor, which has a sensitivity of 0.55°/mM (≈550 Hz/mM) and a detection limit of ≈ 10 nM. Morphology and related roughness parameters of molecularly imprinted polymer surfaces, before and after extraction of DA, as well as that of the non imprinted polymer were characterized by atomic force microscopy. The developed chemosensor selectively recognized dopamine over the structurally similar compound 4‐hydroxyphenethylamine (referred as tyramine), or ascorbic acid,which co‐exists with DA in body fluids at a much higher concentration. Selectivity tests were also carried out with dihydroxybenzene, for which an unexpected phase variation of order of 75% of the DA one was observed. Quantum chemical calculations, based on the density functional theory, were carried out to determine the nature of interactions between each analyte and the PPy matrix and the DA imprinted PPy polypyrrole sensing layer in order to account for the important phase variation observed during dihydroxybenzene injection. Copyright © 2015 John Wiley & Sons, Ltd.     

The Kalash Genetic Isolate: Ancient Divergence,Drift, and Selection

The Kalash represent an enigmatic isolated population of Indo-European speakers who have been living for centuries in the Hindu Kush mountain ranges of present-day Pakistan. Previous Y chromosome and mitochondrial DNA markers provided no support for their claimed Greek descent following Alexander III of Macedon''s invasion of this region, and analysis of autosomal loci provided evidence of a strong genetic bottleneck. To understand their origins and demography further, we genotyped 23 unrelated Kalash samples on the Illumina HumanOmni2.5M-8 BeadChip and sequenced one male individual at high coverage on an Illumina HiSeq 2000. Comparison with published data from ancient hunter-gatherers and European farmers showed that the Kalash share genetic drift with the Paleolithic Siberian hunter-gatherers and might represent an extremely drifted ancient northern Eurasian population that also contributed to European and Near Eastern ancestry. Since the split from other South Asian populations, the Kalash have maintained a low long-term effective population size (2,319–2,603) and experienced no detectable gene flow from their geographic neighbors in Pakistan or from other extant Eurasian populations. The mean time of divergence between the Kalash and other populations currently residing in this region was estimated to be 11,800 (95% confidence interval = 10,600−12,600) years ago, and thus they represent present-day descendants of some of the earliest migrants into the Indian sub-continent from West Asia.     

The specificity of two proteinases that cleave adjacent to arginine, C1 esterase and acrosin, for peptide p-nitroanilide substrates

Relative values of Vmax/Km for hydrolysis of 40 peptide p-nitroanilides catalyzed by human Cl-s and human acrosin are reported. For Cl-s, Ac-Lys(gamma Cbz)-Gly-Arg is the optimum sequence, but 25% of the substrates have (Vmax/Km)rel greater than 0.25 compared to this sequence. The best acrosin substrate tested has the sequence Tos-Gly-Pro-Arg, although (Vmax/Km)rel greater than 0.15 for more than half of the substrates. Proline at P2 is preferred by acrosin. Both enzymes prefer arginine at P1 greater than or equal to 3-fold over lysine and will not accept citrulline. In addition, occupancy of site S3 may yield an increase in Vmax/Km of greater than or equal to 10-fold with either enzyme, but many residues are accepted at S2, S3 and S4. Thus, an acrosin assay using Tos-Gly-Pro-Arg p-nitroanilide as a substrate is more than 20-times as sensitive as existing assays with blocked arginine derivatives.     

A single session of circuit-resistance exercise effects on human peripheral blood lymphocyte ABCA1 expression and plasma HDL-C level

ATP-binding cassette transporters transfer a variety of substrates across the lipid bilayers in an energy-dependent manner. ABCA1 is a member of this family which plays a crucial role in plasma HDL-C metabolism.The purpose of this study was to investigate ABCA1 expression in lymphocytes, plasma lipids and lipoprotein levels in response to a single session of circuit-resistance exercise. Twenty female students volunteered and randomly assigned to control, 40%, 60%, 80% one-repetition maximum groups. Subjects performed a single session of CRE (9 exercises, 25 s per exercise, 3 sets of 3 non-stop circuits, and 1 min rest between the sets). Blood mononuclear cells were isolated for ABCA1 mRNA expression. Plasma glucose, lipids and lipoprotein concentrations were measured. Lymphocyte ABAC1 mRNA expression was significantly (P < 0.001) increased in all given exercise intensities. Total WBC, lymphocyte, neutrophil, platelet counts, plasma glucose, and triglyceride concentrations were also significantly increased after exercise. Changes in plasma HDL-C, LDL-C and TC, concentrations were not significant. In conclusion, a single session of CRE increased PBL ABCA1 expression that was more pronounced in 60% and 40% 1RM groups but not accompanied with significant changes in HDL-C concentrations. Thus, CRE with moderate intensities provide bigger increases of PLB ABCA1 expression not plasma HDL-C levels.     

Large Scale Spatial Variability of Accumulated Cadmium in the Wheat Farm Grains

Cadmium (Cd) accumulation in edible crops is undesirable due to its hazardous influences on human health. The objectives of this study were: i) to evaluate the spatial variability of grain Cd and its relationships with soil properties in 4000 km² wheat farms; ii) to evaluate the effect of wheat cultivar on the soil properties vs. grain Cd relationships. A number of 255 soil (0–20 cm) and grain samples were taken and Cd concentrations in grain samples and some soil properties were measured. Grain Cd concentrations in 95 percent of the samples exceeded the threshold of 0.2 mg kg^?1. Durum wheat had more potential to accumulate Cd in grain (0.76 mg kg^?1) than bread (0.69 mg kg^?1). There was significant (p < 0.01) correlation between grain Cd and organic carbon (r = 0.66), CEC (r = 0.77) and DTPA-extractable Cd (p < 0.05) (r = 0.57) of the soils. Greater Pearson coefficient values for durum wheat showed that, in the studied calcareous soils, organic carbon, CEC, Cd-DTPA had more effects on durum wheat than bread wheat cultivar. The obtained Kriging map of grain Cd identified three hotspots at the east (durum wheat cultivation), the west (intensive irrigated wheat farms), and south (wheat farms around petrochemical industries) of the region. Agricultural mismanagement due to overusing P-fertilizers increased Cd concentration in the topsoils and grains of wheat farms in the study area.     

Effect of different carbon sources on cellulase production by Hypocrea jecorina (Trichoderma reesei) strains

The ascomycete Hypocrea jecorina, an industrial (hemi)cellulase producer, can efficiently degrade plant polysaccharides. At present, the biology underlying cellulase hyperproduction of T. reesei, and the conditions for the enzyme induction, are not completely understood. In the current study, three different strains of T. reesei, including QM6a (wild-type), and mutants QM9414 and RUT-C30, were grown on 7 soluble and 7 insoluble carbon sources, with the later group including 4 pure polysaccharides and 3 lignocelluloses. Time course experiments showed that maximum cellulase activity of QM6a and QM9414 strains, for the majority of tested carbon sources, occurred at 120 hrs, while RUT-C30 had the greatest cellulase activity around 72 hrs. Maximum cellulase production was observed to be 0.035, 0.42 and 0.33 µmol glucose equivalents using microcrystalline celluloses for QM6a, QM9414, and RUTC-30, respectively. Increased cellulase production was positively correlated in QM9414 and negatively correlated in RUT-C30 with ability to grow on microcrystalline cellulose.