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Ribosomes are the macromolecular machines at the heart of protein synthesis; however, their function can be modulated by a variety of additional protein factors that directly interact with them. Here, we report the cryo-EM structure of human Ebp1 (p48 isoform) bound to the human 80S ribosome at 3.3 Å resolution. Ebp1 binds in the vicinity of the peptide exit tunnel on the 80S ribosome, and this binding is enhanced upon puromycin-mediated translational inhibition. The association of Ebp1 with the 80S ribosome centers around its interaction with ribosomal proteins eL19 and uL23 and the 28S rRNA. Further analysis of the Ebp1-ribosome complex suggests that Ebp1 can rotate around its insert domain, which may enable it to assume a wide range of conformations while maintaining its interaction with the ribosome. Structurally, Ebp1 shares homology with the methionine aminopeptidase 2 family of enzymes; therefore, this inherent flexibility may also be conserved.

&ldquo, Pani carasau&rdquo, is a traditional Sardinian bread, made with re-milled durum wheat semolina, with a long shelf-life. The production process is highly energy consuming, but its automation can make it more energy-efficient and sustainable. This requires a deep knowledge of the rheological parameters of the doughs. This study investigated the rheological properties of doughs&mdash, prepared by mixing semolina with water, yeast, and salt&mdash, as a function of the relative amount of the ingredients. The rheological measurements were carried out by an Anton Paar MCR 102 rheometer, equipped with a plate&ndash, plate fixture. In more detail, frequency sweep and creep tests were performed. It was found that doughs obtained with different amounts of ingredients showed significant differences in the rheological responses. The addition of water led to a significant decrease in the viscosity and improved the deformability of the dough. In addition, the yeast addition produced a viscosity decrease, while the presence of salt produced an improvement of the three-dimensional gluten network characteristics and, consequently, of the strength of the dough. In addition to the production process of pani carasau, this work contributes to improving the general performance of the doughs used in the production of flour-and-semolina-based foods.

This article deals with the numerical modeling of the multiphysics investigation of an electric-field-based device for the defluoridation of Ethiopian water to mitigate fluorosis while satisfying the World Health Organization quality requirement for potable water. A tubular reactor with metallic parallel plates, connected to a static voltage source, exerts an electric force on the ion in solution, attracting it to the electrodes. Meanwhile, the ion is drifted by the laminar water flow which, in turn, allows us to separate and collect the F $^{-}$ -rich stream from the potable one. In this system, the electrostatic problem and the mass transport are coupled according to the highly nonlinear modified Poisson–Nernst–Planck–Stokes equations system. Therefore, carefully modeling the dielectric permittivity, the ionic diffusivity, and mobility as function of fluoride concentration and temperature, the set of operating parameters to ensure the highest fluoride removal from Ethiopian thermal water is identified.

We applied micro-scale Spatially Offset Raman Spectroscopy (micro-SORS) to perform the analysis of the layer composition in a fresco of the San Giuseppe church in Cagliari (XVIII century – under restoration). Standard Raman analysis of the surface evidenced the presence of expected pigments in the final plaster layer, such as hematite and calcium sulphate, beside the contribution of calcite. The second one is observed in its anhydrous form on the substrate layers (main Raman peak at 1024 cm−1) and in its hydrate form (1006 cm−1) from the surface. With micro-SORS analysis we evaluated the stratigraphy of the different layers of the plaster by monitoring the intensity ratio of the calcite and the anhydrous calcium sulphate. Four different layers with separation boundaries at about 80 μm, 600 μm and 2400 μm of defocusing distance were evidenced, corresponding to the painting layer “velo”(down to 80 μm), the plaster “rasatura” (down to 600 μm), the “arriccio” layer (down to 2400 μm) and the “rinzaffo” layer (below 2400 μm). The cross-sectional analysis by SEM imaging of a fragment from the fresco confirmed the micro-SORS findings, promoting the technique as a new non-invasive stratigraphy tool for cultural heritage.

n-3 highly unsaturated fatty acids (n-3 HUFA) directly and indirectly regulate lipid metabolism, energy balance and the inflammatory response. We investigated changes to the n-3 HUFA score of healthy adults, induced by different types and amounts of conjugated linoleic acid (CLA)-enriched (ENCH) cheeses consumed for different periods of time, compared to dietary fish oil (FO) pills (500 mg, each containing 100 mg of eicosapentaenoic and docosahexaenoic acids&mdash, EPA+DHA) or &alpha, linolenic acid (ALA)-rich linseed oil (4 g, containing 2 g of ALA). A significant increase in the n-3 HUFA score was observed, in a dose-dependent manner, after administration of the FO supplement. In terms of the impact on the n-3 HUFA score, the intake of ENCH cheese (90 g/day) for two or four weeks was equivalent to the administration of one or two FO pills, respectively. Conversely, the linseed oil intake did not significantly impact the n-3 HUFA score. Feeding ENCH cheeses from different sources (bovine, ovine and caprine) for two months improved the n-3 HUFA score by increasing plasma DHA, and the effect was proportional to the CLA content in the cheese. We suggest that the improved n-3 HUFA score resulting from ENCH cheese intake may be attributed to increased peroxisome proliferator-activated receptor alpha (PPAR-&alpha, ) activity. This study demonstrates that natural ENCH cheese is an alternative nutritional source of n-3 HUFA in humans.

The aim of the research is to investigate the role of the microclimatic conditions and their variations on the decay due to salt crystallisation, observed in a semi-confined archaeological site, in an urban area. A microclimatic monitoring was carried out in the site to detect temperature and relative humidity and their respective variations. Statistical methodology was conducted to examine the microclimatic data with seasonal, monthly and daily analyses. Different zones of the site were monitored and a microclimatic zoning was detected. The outside environment influences the most external zones of the site, while in the confined ones a high relative humidity was detected in all the seasons. The comparison between the hygrothermal conditions monitored in the site and those thermodynamic favourable to salt crystallization revealed a very harmful risk of salt damage for the archaeological structures.

The consumption of phenol during its oxidation process in an aqueous solution containing ferrous ions and hydrogen peroxide (Fenton process) was studied in a microwave irradiated environment at a frequency of 2.45 GHz and at a power of 3 W for different Fe 2+ and phenol initial concentrations; the system was maintained at a constant temperature (25 °C). Experimental results were compared to those obtained in the same system and under the same experimental conditions, but in the absence of irradiation, in order to highlight non-thermal microwave magnetic effects on phenol degradation kinetics, as the temperature of the reacting system was strictly controlled and maintained at the fixed value. This comparison highlighted a great promoting effect of microwaves on the reaction rate not due to a thermal effect, resulting in an about tripled phenol consumption reaction rate; about the same increasing ratio was maintained for systems with the same ratio between ferrous ions and phenol initial concentrations. The authors think that coupling low power microwaves with other advanced oxidation processes for phenol removing, like the Fenton process, could be a very promising method, particularly with respect to costs, as energy consumption is very low if compared to the possible advantages.

Laboratory tests were carried out to determine the primary parameters affecting the efficiency of the process of leaching heavy metals from natural soil collected inside a metallurgical plant in Italy. The soil samples tested consisted primarily of medium density, fine silica sand that had been contaminated with lead and zinc metallurgical wastes by percolating rainwater. Samples were obtained 1–2 m below ground level in an area where the surface consists of artificial strata composed of soil mixed with metallurgical solid waste. The soil layer tested hosts a low-permeability aquifer (at depths generally greater than 10 m below ground level) that is also contaminated by heavy metals. Batch leaching experiments were conducted using acid solutions (acetic, nitric, hydrochloric and sulphuric) as extracting agents. During leaching tests, concentrations of Zn, Pb, Cd, Cu, Mn and Al were monitored. The results indicate that the best leaching solution varies for all analytes and soil samples examined. Statistica...

The effect of different stabilizing techniques on the composition of essential oil of rosemary (Rosmarinus officinalis L.) and thyme (Thymus officinalis L.) during one year of storage is reported. The study was aimed to know what is the stabilizing technique to keep at the best the original essential oil composition. The fresh samples were collected and treated as follows: air-dried in a laboratory scale pilot dryer, frozen in a forced-air freezer and freeze-dried in a laboratory freeze-dryer. The fresh sample served as control. The treated samples were packaged with appropriate packaging material and stored at 20 °C or −20 °C for 12 months. All the samples were hydrodistilled every three months and the oils composition was obtained by means of gas chromatography/mass spectrometry (GC/MS). Quantification of known compounds was done with the use of an internal standard. Freezing best maintained the composition of rosemary and thyme essential oil. Appropriate packaging of air-dried and freeze-dried herbs resulted in negligible quality loss up to one year of storage. The frozen and stored thyme samples showed the best retention of thymol, the most important compound, as well as of γ-terpinene and carvacrol.

Fyn is a member of the Src-family of nonreceptor protein-tyrosine kinases. Its abnormal activity has been shown to be related to various human cancers as well as to severe pathologies, such as Alzheimer's and Parkinson's diseases. Herein, a structure-based drug design protocol was employed aimed at identifying novel Fyn inhibitors. Two hits from commercial sources (1, 2) were found active against Fyn with K(i) of about 2 μM, while derivative 4a, derived from our internal library, showed a K(i) of 0.9 μM. A hit-to-lead optimization effort was then initiated on derivative 4a to improve its potency. Slightly modifications rapidly determine an increase in the binding affinity, with the best inhibitors 4c and 4d having K(i)s of 70 and 95 nM, respectively. Both compounds were found able to inhibit the phosphorylation of the protein Tau in an Alzheimer's model cell line and showed antiproliferative activities against different cancer cell lines.

Nefopam (NEF) is a known analgesic that has recently been shown to be effective in controlling both neuropathic pain and convulsions in rodents. In this study we compared nefopam to carbamazepine (CBZ), a reference antiepileptic drug (AED), for their ability to protect cerebellar neuronal cultures from neurodegeneration induced by veratridine (VTD). Furthermore, we tested nefopam for protection against both, maximal electroshock-induced seizures (MES), and isoniazid-induced seizures in mice. Both NEF and CBZ were effective in preventing both signs of excitotoxicity and neurodegeneration following exposure of cultures to 5 µM veratridine for 30 min and 24 h, respectively. Concentrations providing full neuroprotection were 500 µM CBZ and 50 µM NEF, while the concentration providing 50% neuroprotection was 200 µM for CBZ and 20 µM for NEF. Neither NEF nor CBZ reduced excitotoxicity following direct exposure of cultures to glutamate, but CBZ failed to reduce increases in intracellular calcium following stimulation of L-type voltage sensitive calcium channels. In vivo, NEF (20 mg/kg i.p.) significantly reduced MES and fully prevented MES-induced terminal clonus (TC). In comparison, NEF was significantly more effective than CBZ in preventing MES, although both drugs were equally effective against MES-induced TC. Furthermore, nefopam provided protection against isoniazid-induced seizures at doses similar to those protecting against MES.

Objectives: The analytical performance of a new automated HPLC system (Tosoh HLV-723 G7) for Hb A 2 and Hb F quantification in blood was studied. Design and methods: Hb A 2 and Hb F measurements were studied for imprecision, linearity, carry-over, interferences and sample concentration effect. Method comparison study was performed with the Bio-Rad Variant II HPLC system. Hb F results were also compared with those obtained by the alkaline denaturation test. The detection of some common Hb variants was also studied. Results: Hb A 2 within-run and between-run CVs were found between 0.8–2.2% and 2.9–7.2%, respectively, while CVs for Hb F were up to 10.0% in normal and between 1.9–5.3% at more clinically relevant Hb F concentrations (>1.5%). Comparison study with Bio-Rad Variant II for Hb A 2 determination showed good correlation but highlighted calibration differences. The following results were obtained in two different laboratories: y = 1.163 x − 0.52, r = 0.9918, n = 144 (Lab A); y = 1.060 x − 0.40, r = 0.9920, n = 93 (Lab B). With regard to the determination of Hb F, the measurements performed by the tested method was found to correlate well with the alkaline denaturation test ( y = 1.0138 x − 0.36, r = 0.9842, n = 20) and with the Variant II HPLC system ( y = 0.812 x + 0.52, r = 0.9835, n = 110). An excellent linearity ( r = 0.999) was found for both Hb A 2 and Hb F in the range 0.8–19%. Hb S, Hb C and Hb D can be presumptively identified by the assigned retention time windows. Conclusion: The new analyzer Tosoh HLV-723 G7 was found to be a reliable method for Hb A 2 and Hb F quantification and for the presumptive identification of some common Hb variants.

Helichrysum italicum ssp. microphyllum extract was isolated by supercritical CO2 extraction with a fractional separation technique. Operative conditions were: extractor, 90 bar and 50°C for 240 min; first separator, 90 bar and -10°C; second separator, 15 bar and 15°C. GC/MS analysis of the leaf volatile concentrate revealed that it mainly consisted of neryl acetate (26.0%), nerol (9.1%), neryl propionate (6.7%), γ-curcumene (10.8%) and cis-dihydro-occidentalol (4.3%). The differences observed between the composition of the SFE volatile concentrate and the hydrodistilled oil were minor.

This review focuses on the application of click chemistry in medicinal sciences, and particularly on its role in drug discovery. Because of its high modularity, click chemistry helps to accelerate the current drug discovery process, which relies on massive screening of chemical libraries. This article describes examples of click chemistry applications that are aimed at finding new lead candidates against pathologies such as cancer, AIDS and Alzheimer's disease, and explores the impact that the technique could have in therapy and prevention in the near future, through application in drug delivery systems, bioconjugation and diagnostic. An introduction, addressed to researchers who intend to use this methodology, examines the opportunities to perform click reactions according to the most common and best studied techniques, such as synthesis in water, on solid phase, and under microwave or ultrasound irradiation. Every topic is furnished with examples which have appeared in the literature in the last five years and is clarified by schemes and figures.

Aminoacyl-tRNA synthetases play a key role in protein biosynthesis by catalyzing the specific aminoacylation of tRNA. The energy required for the formation of the ester bond between the amino acid carboxylate group and the tRNA acceptor stem is supplied by coupling the reaction to the hydrolysis of ATP. Lysyl-tRNA synthetase from Escherichia coli belongs to the family of class II synthetases and carries out a two-step reaction, in which lysine is activated by being attached to the alpha-phosphate of AMP before being transferred to the cognate tRNA. Crystals of the thermo-inducible E. coli lysyl-tRNA synthetase LysU which diffract to 2.1 A resolution have been used to determine crystal structures of the enzyme in the presence of lysine, the lysyl-adenylate intermediate, and the nonhydrolyzable ATP analogue AMP-PCP. Additional data have been obtained from crystals soaked in a solution containing ATP and Mn(2+). The refined crystal structures give "snapshots" of the active site corresponding to key steps in the aminoacylation reaction and provide the structural framework for understanding the mechanism of lysine activation. The active site of LysU is shaped to position the substrates for the nucleophilic attack of the lysine carboxylate on the ATP alpha-phosphate. No residues are directly involved in catalysis, but a number of highly conserved amino acids and three metal ions coordinate the substrates and stabilize the pentavalent transition state. A loop close to the catalytic pocket, disordered in the lysine-bound structure, becomes ordered upon adenine binding.

This paper reports the investigation aimed at verifying the influence of potassium dihydrogen phosphate and ferric chloride hexahydrate on stabilization/solidification (S/S) processes applied to tailing waste from a Pb and Zn mineral processing plant. The use of cement alone (in a percentage equal to 5%) does not permit the obtaining of a final product complying with current Italian legislation. The possibility of using potassium dihydrogen phosphate, singly or combined with ferric chloride hexahydrate, has been investigated under different pH conditions, simulating the aging phase in waste–cement mixtures. The combined effect of the additives mentioned (1% KH 2 PO 4 and 1% FeCl 3 ), together with small quantities of cement, permits production of inert material, through the physical encapsulation and formation of stable compounds.

A plug flow reactor (PFR) which permits the growth of bacteria in a microwave environment is described. The apparatus is used to analyse the effect of microwave radiation at the frequency of 2.45 GHz and at 37°C on the growth rate of three bacterial species: Bacillus clausii, Pseudomonas aeruginosa, and Staphylococcus aureus. The growth constant is determined for reacting mixtures irradiated with microwaves of different powers ranging from 0 to 400 mW. Analyses show that (a) the apparatus is able to perform the experimental runs maintaining an aseptic environment; (b) under the microwave power levels examined in the present study, no effects are detected for the Bacillus clausii and Pseudomonas aeruginosa species, while for the Staphylococcus aureus species, a few small effects are found (a minimum value of the growth constant at 200 mW and an increase of the constant between 200 and 400 mW). © 2009 American Institute of Chemical Engineers AIChE J, 2010

Cottage cheese whey is a cheese industry by-product still rich in proteins and lactose. Its recycling is seldom cost-effective. In this work we show that the lactose-utilizing yeast Kluyveromyces lactis , engineered for production of recombinant human lysozyme, can be grown in cottage cheese whey, resulting in high-level production of the heterologous protein (125 μg/ml).

Objectives: In this paper we describe the outline and results of a 7-year screening programme for thalassaemias and glucose-6-phosphate dehydrogenase (G6PD) deficiency in 13- to 14-year-old students from the Sardinian population. Method: This programme had several steps: formal education on thalassaemia, request of informed consent by parents, blood testing and genetic counselling. Results:Out of 63,285 subjects tested, 6,521 (10.3%) were heterozygotes for β-thalassaemia, 16,175 (25.6%) for α-thalassaemia and 101 were carriers of a haemoglobin variant. One thousand four hundred and twenty (16.4%) males were hemizygotes for G6PD deficiency and 1,893 (20.6%) females were heterozygotes. Conclusion: The uptake of the programme was remarkably high and homogeneous across the island, indicating and confirming a great interest of the Sardinian population in any initiative directed at the prevention of homozygous β-thalassaemia.

International audience; Lysyl-tRNA synthetase is a member of the class II aminoacyl-tRNA synthetases and catalyses the specific aminoacylation of tRNA(Lys). The crystal structure of the constitutive lysyl-tRNA synthetase (LysS) from Escherichia coli has been determined to 2.7 A resolution in the unliganded form and in a complex with the lysine substrate. A comparison between the unliganded and lysine-bound structures reveals major conformational changes upon lysine binding. The lysine substrate is involved in a network of hydrogen bonds. Two of these interactions, one between the alpha-amino group and the carbonyl oxygen of Gly 216 and the other between the carboxylate group and the side chain of Arg 262, trigger a subtle and complicated reorganization of the active site, involving the ordering of two loops (residues 215-217 and 444-455), a change in conformation of residues 393-409, and a rotation of a 4-helix bundle domain (located between motif 2 and 3) by 10 degrees. The result of these changes is a closing up of the active site upon lysine binding.

We report the identification and characterisation of a DNA primase from the thermophilic methanogenic archaeon Methanococcus jannaschii (Mjpri). The analysis of the complete genome sequence of this organism has identified an open reading frame coding for a protein with sequence similarity to the small subunit of the eukaryotic DNA primase (the p50 subunit of the polymerase alpha-primase complex). This protein has been overexpressed in Escherichia coli and purified to near homogeneity. Recombinant Mjpri is able to synthesise oligoribonucleotides on various pyrimidine single-stranded DNA templates [poly(dT) and poly(dC)]. This activity requires divalent cations such Mg(2+), Mn(2+)or Zn(2+), and is additionally stimulated by the monovalent cation K(+). A multiple sequence alignment has revealed that most of the regions that are conserved in eukaryotic p50 subunits are also present in the archaeal primases, including the conserved negatively charged residues, which have been shown to be essential for catalysis in the mouse primase. Of the four cysteine residues that have been postulated to make up a putative Zn-binding motif, two are not present in the archaeal homologue. This is the first report on the biochemical characterisation of an archaeal DNA primase.

This article studies the use of capacitive sensors for in situ calibration of the piezoscanner of a scanning tunneling microscope (STM). Nonlinearities, hysteresis, and creeps of piezoactuators are the main sources of the uncertainty in the tip position while scanning the sample surface to be imaged. In order to compensate for these effects in the reconstruction of the surface topography, capacitive sensors have been coupled to a piezoscanner of a STM operating in air. This scanner provides x,y,z displacements up to about 130 μm×130 μm×30 μm, and consists of bimorph plates mounted in a parallelogram arrangement. The capacitive sensors are inserted in a differential configuration to minimize capacitance variations due to changes in humidity and temperature of the air and to compensate for thermal drifts of the structure. As a performance test, the piezoscanner displacements were independently measured by means of a differential interferometer. A linearity within 3% and a deviation within 0.3% from the expe...

Content of fluoride compounds in some typical Ethiopian water sources was analysed and several commonly available soils were characterized for their adsorption properties regarding the water defluoridation. Various soils were collected in different Ethiopian sites and the samples were analysed by X-ray diffractometry for their mineralogical composition. Batch experimental runs at room temperature were performed to evaluate the adsorption capacity of each soil sample as well as to deduce the adsorption isotherms of fluoride ions with respect to the examined soils. The best soil was identified in terms of adsorption capacity and considered for the design of two different adsorption apparatuses. Considering the water consumption of a small rural community, the capacity of the adsorption unit was selected to assure a reduction of the fluoride concentration in drinking water to the limits recommended by the World Health Organization and to allow a suitable working time of the adsorption unit before the replacement of adsorbent would be necessary.