Oxidative Folding of Proteins: The “Smoking Gun” of Glutathione

Glutathione has long been suspected to be the primary low molecular weight compound present in all cells promoting the oxidative protein folding, but twenty years ago it was found “not guilty”. Now, new surprising evidence repeats its request to be the “smoking gun” which reopens the criminal trial revealing the crucial involvement of this tripeptide.     

Integrated analysis of cooling water systems: Modeling and experimental validation

Cooling towers are widely used in many industrial and utility plants as a cooling medium, whose thermal performance is of vital importance. Despite the wide interest in cooling tower design, rating and its importance in energy conservation, there are few investigations concerning the integrated analysis of cooling systems. This work presents an approach for the systemic performance analysis of a cooling water system. The approach combines experimental design with mathematical modeling. An experimental investigation was carried out to characterize the mass transfer in the packing of the cooling tower as a function of the liquid and gas flow rates, whose results were within the range of the measurement accuracy. Then, an integrated model was developed that relies on the mass and heat transfer of the cooling tower, as well as on the hydraulic and thermal interactions with a heat exchanger network. The integrated model for the cooling water system was simulated and the temperature results agree with the experimental data of the real operation of the pilot plant. A case study illustrates the interaction in the system and the need for a systemic analysis of cooling water system. The proposed mathematical and experimental analysis should be useful for performance analysis of real-world cooling water systems.     

Effects of Surface Morphology on the Wear and Corrosion Resistance of Post-Treated Nitrided and Nitrocarburized 42CrMo4 Steel

The surface of alloyed carbon steel was subjected to thermochemical modification by nitrocarburizing and nitriding with or without postoxidation in order to improve its mechanical properties, corrosion, and wear resistance. Treated samples were characterized by testing their basic properties (compound layer thickness, nitriding, nitrocarburizing depth, and surface hardness) according to standards. Detailed estimation of the modified metal surface was performed by additional testing: X-ray diffraction, microstructure, surface roughness and topography, and wear and corrosion resistance. The surface layer obtained after nitrocarburizing treatment consists mainly of ε-Fe_2-3(N,C) and γ’-Fe₄(N,C); similarly, the nitrided surface is formed by ε-Fe_2-3N and γ’-Fe₄N iron nitrides. The surface layer after postoxidation contains additionally Fe₃O₄. The results obtained show that nitrocarburization, nitridation, and postoxidation result in better mechanical, wear, and corrosion resistance of 42CrMo4 steel, and postoxidized sample properties are influenced by surface morphology.     

Oxidative Stress-Related Signaling Pathways Predict Oocytes’ Fertilization In Vitro and Embryo Quality

Oocyte development and fertilization are largely influenced by the microenvironment of the follicular fluid (FF), and the exploration of its molecular/metabolic composition may help in improving in vitro fertilization (IVF) outcomes. Here, the concentrations of molecules related to oxidative stress/inflammation were measured in FF from follicles at oocyte retrieval during IVF. Here, the FF antioxidant potential was correlated with the number of retrieved/mature oocytes and the number of fertilized ones. FF collected from the follicles of normal fertilized oocytes presented an elevated antioxidant capability, lower levels of pro-inflammatory molecules (i.e., IL-6, IL-8, IL-12, TGF-β, and HIF-1α), and a higher IL-10 concentration. FF samples from follicles at oocyte retrieval that resulted in top-quality embryos displayed a peculiar antioxidant capability and a further decrease in proinflammatory molecules when compared with FF, giving rise to poor-quality embryos. Finally, pro-inflammatory molecules were lower and accompanied by a high antioxidant capability in samples giving rise to successful embryo implantation. The antioxidant capability and IL-10 displayed a good predictive ability for fertilization and embryo quality. Overall, our data showed the great influence of oxidative stress on the oocytes’ fertilization, and shed light on the importance of controlling the inflammatory and oxidative status of FF to obtain good-quality embryos with significant implantation potential.     

In Vivo Bio-Activation of JWH-175 to JWH-018: Pharmacodynamic and Pharmacokinetic Studies in Mice

3-(1-Naphthalenylmethyl)-1-pentyl-1H-indole (JWH-175) is a synthetic cannabinoid illegally marketed for its psychoactive cannabis-like effects. This study aimed to investigate and compare in vitro and in vivo pharmacodynamic activity of JWH-175 with that of 1-naphthalenyl (1-pentyl-1H-indol-3-yl)-methanone (JWH-018), as well as evaluate the in vitro (human liver microsomes) and in vivo (urine and plasma of CD-1 male mice) metabolic profile of JWH-175. In vitro binding studies showed that JWH-175 is a cannabinoid receptor agonist less potent than JWH-018 on mouse and human CB1 and CB2 receptors. In agreement with in vitro data, JWH-175 reduced the fESPS in brain hippocampal slices of mice less effectively than JWH-018. Similarly, in vivo behavioral studies showed that JWH-175 impaired sensorimotor responses, reduced breath rate and motor activity, and increased pain threshold to mechanical stimuli less potently than JWH-018. Metabolic studies demonstrated that JWH-175 is rapidly bioactivated to JWH-018 in mice blood, suggesting that in vivo effects of JWH-175 are also due to JWH-018 formation. The pharmaco-toxicological profile of JWH-175 was characterized for the first time, proving its in vivo bio-activation to the more potent agonist JWH-018. Thus, it highlighted the great importance of investigating the in vivo metabolism of synthetic cannabinoids for both clinical toxicology and forensic purposes.     

Miniaturization of the QuEChERS Method in the Fast Gas Chromatography-Tandem Mass Spectrometry Analysis of Pesticide Residues in Vegetables

Two reduced-scale quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedures, combined with fast gas chromatography-triple quadrupole mass spectrometry (GC-QqQ MS), were developed and then validated for the determination of 35 pesticides in different vegetable products (tomatoes, zucchini, red peppers, and lettuce). The proposed reduced-scale methods, involving the use of only 3 g of sample, were compared with an official European Union method, namely EN15662:2008, based on the use of a 10-g sample. Method validation was performed considering the following figures of merit: recovery, linearity, precision, matrix effects, and limits of detection and quantification. Specifically, recovery was in the 67–126% range, regression coefficients were between 0.991 and 0.999, and coefficients of variation were between 1 and 13% (at the 50 μg kg^?1 level), while limits of quantification were always below European legislation residue limits. Additionally, the measurement of matrix effects confirmed the necessity of matrix-matched calibration. The developed QuEChERS GC-QqQ MS method is both simple and rapid (analysis of six samples in 2.5 h) and is sensitive enough for EU regulation purposes. To demonstrate the applicability of the proposed reduced-scale method, multi-residue analysis was performed on 20 samples.     

Reuse of Dairy Product: Evaluation of the Lipid Profile Evolution During and After Their Shelf-Life

The aim of the present work was the characterization of best-by-date dairy products to evaluate their nutritional value for possible re-introduction in the food or feed chain. The attention was devoted to fatty acids and triacylglycerols characterization and their variation during storage of fresh-cheese products before and after their best-by-date. Three kinds of cheese were selected, namely a classic stracchino, stracchino with the addition of yogurt, and one with the addition of probiotic. The variation of FAMEs and TAGs profiles were studied in order to evaluate the degree of variation occurring in the lipid fraction during storage and after the best-by-date. The extraction method was simply scaled-down by ten-fold, starting from the classical Schmid–Bondzynski–Ratzlaff method. The GC run was sped up after a careful comparison of the result with a conventional analysis. The entire data set of results was evaluated performing both a three-way principal component analysis and a traditional two-way one. The three kinds of samples were well discriminated while a change of the lipid profile over the best-by-date period was particularly significant only for the stracchino added with a probiotic.     

Age differences in information finding tasks: Performance and visual exploration strategy with different web page layouts

Recent research suggests that older Internet users seem to find it more difficult to locate navigation links than to find information content in web pages. One possibility is that older Internet users’ visual exploration of web pages is more linear in nature, even when this type of processing is not appropriate for the task. In the current study, the eye movements of young and older Internet users were recorded using an ecological version of the web pages or a discursive version designed to induce a linear exploration. The older adults found more targets when performing content-oriented compared to navigation-oriented searches, thus replicating previous results. Moreover, they performed less well than young people only when required to locate navigation links and tended to outperform the younger participants in content-oriented searches. Although the type of search task and type of web page resulted in different visual strategies, little or no support was found for the hypothesis that older participants explore web pages in a more linear way in cases where this strategy was not appropriate. The main conclusion is that differences in visual exploration do not seem to mediate the specific difficulty older adults experience in navigation-oriented searches in web pages.     

Effects of oxytocin and prosocial behavior on brain responses to direct and vicariously experienced pain.

In this study, we tested the validity of 2 popular assumptions about empathy: (a) empathy can be enhanced by oxytocin, a neuropeptide known to be crucial in affiliative behavior, and (b) individual differences in prosocial behavior are positively associated with empathic brain responses. To do so, we measured brain activity in a double-blind placebo-controlled study of 20 male participants either receiving painful stimulation to their own hand (self condition) or observing their female partner receiving painful stimulation to her hand (other condition). Prosocial behavior was measured using a monetary economic interaction game with which participants classified as prosocial (N = 12) or selfish (N = 6), depending on whether they cooperated with another player. Empathy-relevant brain activation (anterior insula) was neither enhanced by oxytocin nor positively associated with prosocial behavior. However, oxytocin reduced amygdala activation when participants received painful stimulation themselves (in the nonsocial condition). Surprisingly, this effect was driven by "selfish" participants. The results suggest that selfish individuals may not be as rational and unemotional as usually suggested, their actions being determined by their feeling anxious rather than by reason. (PsycINFO Database Record (c) 2010 APA, all rights reserved)