Effect of ultrasound therapy on the repair of gastrocnemius muscle injury in rats

The aim of this study was to evaluate the effect of the pulsed ultrasound therapy (PUT) in stimulating myoregeneration and collagen deposition in an experimental model of lacerative gastrocnemius muscle lesion in 30 Wistar rats. Fifteen rats were treated (TG) daily with 1 MHz pulsed ultrasound (50%) at 0.57 W/cm² for 5 min, and 15 were control animals (CG). Muscle samples were analyzed on postoperative days 4, 7 and 14 through H&E, Picrosirius-polarization and immunohistochemistry for desmin. The lesions presented similar inflammatory responses in both treated and control groups. The areal fraction of fibrillar collagen was larger in the TG at 4 days post-operatively (17.53 ± 6.2% vs 6.79 ± 1.3%, p = 0.0491), 7 days (31.07 ± 7.45% vs 12.57 ± 3.6%, p = 0.0021) and 14 days (30.39 ± 7.3% vs 19.13 ± 3.51%, p = 0.0118); the areal fraction of myoblasts and myotubes was larger in the TG at 14 days after surgery (41.66 ± 2.97% vs 34.83 ± 3.08%, p = 0.025). Our data suggest that the PUT increases the differentiation of muscular lineage cells, what would favor tissue regeneration. On the other hand, it is also suggested that there is a larger deposition of collagenous fibers, what could mean worse functional performance. However, the percentage of fibers seems to have stabilized at day 7 in TG and kept increasing in CG. Furthermore, the collagen supramolecular organization achieved by the TG is also significant according to the Sirius red staining results.     

Multimodal imaging: an evaluation of univariate and multivariate methods for simultaneous EEG/fMRI

The combination of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) has been proposed as a tool to study brain dynamics with both high temporal and high spatial resolution. Multimodal imaging techniques rely on the assumption of a common neuronal source for the different recorded signals. In order to maximally exploit the combination of these techniques, one needs to understand the coupling (i.e., the relation) between electroencephalographic (EEG) and fMRI blood oxygen level-dependent (BOLD) signals.     

Kindergartners’ performance in length measurement and the effect of picture book reading

This paper addresses: firstly, kindergartners’ performance in length measurement, the components of their performance and its growth over time; secondly, the possibility to develop kindergartners’ performance in length measurement by reading to them from picture books. To answer the research questions, an experiment with a pretest–posttest experimental control group design was carried out involving nine experimental classes and nine control classes. The children in the experimental group participated in a 3-month picture book program that, among other things, spotlighted the measurement of length situated in meaningful contexts. Before and after the intervention, the children’s performance in length measurement was assessed in both groups. The responses of 308 kindergartners (4- to 6-year-olds) from two kindergarten years (K1 and K2) were analyzed. Analysis of the pretest data showed that the measurement tasks included in the test were not easy to solve. However, the children belonging to K2 did better than the younger children belonging to K1. Within children’s performance, three components could be identified: holistic visual recognition, ordering and unitizing. Finally, the effect of the intervention was investigated by comparing the performances of the experimental and control group in the pretest and the posttest. We found a weak but significant effect of reading picture books to children on their general measurement performance. However, this effect was only found for K1 children on the component of holistic visual recognition.     

A quantitative chemiluminescent assay for analysis of peroxide-based explosives

A quantitative chemiluminescent method, enabling indirect identification of the peroxide-based explosives TATP (triacetone triperoxide) and HMTD (hexamethylene triperoxide diamine) has been developed. Treatment of these compounds with acidic solutions produced peroxides, which were transformed into radical derivatives by horseradish peroxidase (HRP) and then quantified by measuring the light emitted during their oxidation of luminol. The method was first developed in the microplate format and later optimized for a portable luminometer, to enable rapid application of the assay directly on site. When the portable luminometer was used each analysis took only 5–10 min. The method had good selectivity, sensitivity, and reproducibility; in the microplate format the limits of detection (LOD) and quantification (LOQ) were 40 and 50 ng mL⁻¹, respectively, for both TATP and HMTD. When the portable luminometer was used the LOD and LOQ were 50 and 100 ng mL⁻¹, respectively, for both compounds. Introduction of light emission-enhancing compounds did not improve the analytical performance of the assay. Imprecision (CV values) was always below 10%. Recovery varied rapidly with time, with an average value of 78% after 5 min. No false-positive result was detected on measurement of a variety of samples; this is an important feature for analysis on site. The method was applied both to contaminated materials and to fortified soil samples, simulating operational conditions.     

A kinetic study of the interaction of DNA with gold nanoparticles: mechanistic aspects of the interaction

A kinetic study of the interaction of gold nanoparticles capped with N-(2-mercaptopropionyl)glycine with double stranded DNA was carried out in water and in salt (NaCl) solutions. The kinetic curves are biexponential and reveal the presence of three kinetic steps. The dependence of the reciprocal fast and slow relaxation time, on the DNA concentration, is a curve and tends to a plateau at high DNA concentrations. The simplest mechanism consistent with the kinetic results involves a simple three-step series mechanism reaction scheme. The first step corresponds to a very fast step that is related to a diffusion controlled formation of an external precursor complex (DNA, AuNPs); the second step involves the formation of a (DNA/AuNPs)(I) complex, as a result of the binding affinity between hydrophilic groups of the tiopronin and the DNA grooves. Finally, the third step has been interpreted as a consequence of a conformational change of the (DNA/AuNPs)(I) complex formed in the second step, to a more compacted form (DNA/AuNPs)(II). The values of the rate constants of each step decrease as NaCl concentration increases. The results have been discussed in terms of solvation of the species and changes in the viscosity of the solution.     

Design of an NO photoinduced releaser xerogel based on the controlled nitric oxide donor trans-[Ru(NO)Cl(cyclam)](PF6)2 (cyclam=1,4,8,11-tetraazacyclotetradecane)

The immobilization and properties of the nitric oxide donor trans-[Ru(NO)Cl(cyclam)](PF(6))(2), RuNO, entrapped in a silica matrix by the sol-gel process is reported herein. The entrapped nitrosyl complex was characterized by spectroscopic (UV-vis, infrared (IR), X-ray photoelectron, and (13)C and (29)Si MAS NMR) and electrochemical techniques. The entrapped species exhibit one characteristic absorption band in the UV-vis region of the electronic spectrum at 354 nm and one IR nu(NO) stretching band at 1865 cm(-1), as does the RuNO species in aqueous solution. Our results show that trans-[Ru(NO)Cl(cyclam)](PF(6))(2) can be entrapped in a SiO(2) matrix with preservation of the molecular structure. However, in a SiO(2)/SiNH(2) matrix, the complex undergoes a nucleophilic attack by the amine group at the nitrosonium. Irradiation of the complex, entrapped in the SiO(2) matrix, with light of 334 nm, resulted in NO release. The material was regenerated to its initial nitrosyl form by reaction with nitric oxide.     

Technology of production of red figure pottery from Attic and southern Italian workshops

Samples from Greek figure vases were investigated by scanning electron microscopy coupled with energy dispersive X-ray analysis, X-ray diffraction, thermomechanical analysis and reflectance spectroscopy to achieve a technological characterisation. The vases, dating from the end of the sixth to the fourth century BC, had been excavated at Locri Epizephiri (Calabria, Italy) and attributed to Attic or local workshops, respectively. Information on the morphology of black slip areas and firing temperatures was compared with that previously obtained for Attic and local black gloss pottery from the same site; results show that the peculiar technique required for the production of black slips was mastered by both Attic and local potters and employed for monochrome and figured products. The black coating is usually well vitrified and 15- to 20-m thick; the evaluated maximum firing temperature is around 900°C, while a temperature lower than 800°C is generally estimated for ceramic body re-oxidation.     

Weak stereospecific interactions in water. Excess enthalpies of aqueous solutions containing aldopyranosides at 25°C

The heats of dilution in water of methyl--D-galacto-, gluco-, and xylopyranosides and the heats of mixing with the respective -isomers were determined calorimetrically at 25°C. The excess enthalpies, expressed as virial expansions as a function of the molalities, lead to the evaluation of the self- and cross-interaction coefficients. As for other saccharide derivatives, the pairwise interaction coefficients are positive and larger than those for the parent monosacharides. The cross coefficients, in turn, are smaller than the homogeneous coefficients resulting in a favorable contribution to the free energy of mixing. This indicates the existence of a weak, water-mediated, but still stereospecific recognition between pairs of solute molecules.