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Surface modification of medical implants is often required to improve their biocompatibility or, through bioactive properties of the surface material, facilitate its intergrowth with the living tissue. Bioactive-glass coatings can serve that purpose for the bone implants. We report a successful preparation of silicate-phosphate bioactive-glass coating on titanium substrate using the pulsed laser deposition method and present the coating characterization in terms of bonding configuration and chemical activity. The former was studied with high-resolution Raman microspectroscopy and revealed the presence of structural units responsible for the material's bioactivity. The bioactivity was also tested directly, in vitro, by soaking the samples in the simulated body fluid and examining the result with the Raman spectroscopy. The Raman spectrum, typical of hydroxyapatite was observed proving that the bone-like-material formed on the coating's surface. [ABSTRACT FROM AUTHOR]

Abstract: In this study a typical grey-brown podzolic soil was amended with different doses of a brown coal-based preparation called Rekulter (R) largely used in Poland. After seven years, soils were analyzed and humic acids (HAs) were extracted both from the control soil and from the amended soils. All HAs were characterized by Fourier transform infrared spectroscopy and fluorescence spectroscopy both in emission, excitation and synchronous-scan mode and as Excitation–Emission-Matrix (EEM) contour maps. A higher carbon content was observed in the amended soils whereas significant differences were highlighted between the unamended and the amended soil HAs. HAs from amended soils showed a higher content of carboxyl groups and a more aromatic character, particularly HA extracted from the soil amended with the highest dose of R. [Copyright &y& Elsevier]

Modeling stroke in animals is essential for testing efficacy of new treatments; however, previous neuroprotective therapies, based on systemic delivery in rodents failed, exposing the need for model with improved clinical relevance. The purpose of this study was to develop endovascular approach for inducing ischemia in swine. To achieve that goal, we used intra-arterial administration of thrombin mixed with gadolinium and visualized the occlusion with real-time MRI. Placement of the microcatheter proximally to rete allowed trans-catheter perfusion of the ipsilateral hemisphere as visualized by contrast-enhanced perfusion MR scans. Dynamic T2*w MRI facilitated visualization of thrombin + Gd solution transiting through cerebral vasculature and persistent hyperintensities indicated occlusion. Area of trans-catheter perfusion dynamically quantified on representative slice before and after thrombin administration (22.20 ± 6.31 cm2 vs. 13.28 ± 4.71 cm2 respectively) indicated significantly reduced perfusion. ADC mapping showed evidence of ischemia as early as 27 min and follow-up T2w scans confirmed ischemic lesion (3.14 ± 1.41 cm2). Animals developed contralateral neurological deficits but were ambulatory. Our study has overcome long lasting challenge of inducing endovascular stroke model in pig. We were able to induce stroke using minimally invasive endovascular approach and observe in real-time formation of the thrombus, blockage of cerebral perfusion and eventually stroke lesion. [ABSTRACT FROM AUTHOR]

Cyclophosphamide (CPX) is an anticancer drug with immunosuppressive properties. Its adverse effects are partly connected to the induction of oxidative stress. Some studies indicate that water-soluble derivative of morin—morin-5′-sulfonic acid sodium salt (NaMSA) exhibits strong antioxidant activity. The aim of present study was to evaluate the effect of NaMSA on CPX-induced changes in oxido-redox state in rat. Experiment was carried out on Wistar rats divided in three experimental groups (N = 12) receiving: 0.9% saline, CPX (15 mg/kg) or CPX (15 mg/kg) + NaMSA (100 mg/kg), respectively, and were given intragastrically for 10 days. Malondialdehyde (MDA) and glutathione (GSH) concentrations and superoxide dismutase (SOD) activity were determined in liver and kidneys. Catalase (CAT) activity was assessed only in liver. Treatment with CPX resulted in significant decrease in MDA level in both tissues, which was completely reversed by NaMSA treatment only in liver. In comparison to the control group significant decrease in SOD activity were observed in both tissues of CPX receiving group. In kidneys this parameter was fully restored by NaMSA administration. CPX evoked significant decrease in GSH concentration in kidneys, which was completely reversed by NaMSA treatment. No significant changes were seen in GSH levels and CAT activity between all groups in liver. Results of our study suggest that CPX may exert significant impact on oxido-redox state in both organs. NaMSA fully reversed the CPX-induced changes, especially MDA level in liver, SOD activity and GSH concentration in kidneys and it may be done by enhancement of activity/concentration of endogenous antioxidants. [ABSTRACT FROM AUTHOR]

Protective oxide coating of p-n junctions in HPGe detectors is investigated. Owing to this coating, HPGe detectors can be used, in particular, in liquid nitrogen environment without capsulation. A simple and practically feasible method for forming the protective layer by processing detectors in methanol is described. It is shown that this layer reliably protects p-n junctions of HPGe detectors from environmental impact. The characteristics of the protective oxide film are investigated using the Raman scattering method. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the effect of the prolonged intake of three β-blocking drugs (propranolol, metoprolol and nebivolol) on the sexual behavior and penile microcirculation of rabbits. Drugs were administered p.o. for 9 weeks and every three weeks in each group (n=13) one subgroup (n=7) performed behavioral tests, whereas in the second subgroup (n=6) penile microcirculation was measured with a laser Doppler flowmeter. The copulation studies revealed significant impairment of sexual function only in the propranolol treated group. The measured behavioral parameters suggest that at a given dose propranolol affects more performance rather than arousal aspects of rabbits' sexual behavior. In the course of the whole study no significant difference was observed among groups in penile blood flow. The data indicate that among the β-blockers given only propranolol interferes with sexual behavior, and that β-blockers do not appear to have a negative effect on penile microcirculation.International Journal of Impotence Research (2007) 19, 49–54. doi:10.1038/sj.ijir.3901485; published online 11 May 2006 [ABSTRACT FROM AUTHOR]

A reconstruction technique based on the solution of the Radon transform in terms of Jacobi polynomials is used to obtain the 3D electron momentum density, ϱ(p), from nine high-resolution Compton profiles (CPs) for a Cu[sub 0.9] Al[sub 0.1] disordered alloy single crystal. The method was also applied to theoretical CPs computed within the Korringa–Kohn–Rostoker coherent potential approximation (KKR-CPA) first-principles scheme for the same nine orientations of the crystal. The experimental ϱ(p) is in satisfactory agreement with the theoretical ϱ(p), shows most details of the Fermi surface (FS) and exhibits electron correlation effects. We comment on the map of the FS obtained by folding the reconstructed ϱ(p) into the first Brillouin zone, which yields the occupation number density, ϱ(k). A test of the validity of data via a consistency condition (within our reconstruction algorithm) as well as the propagation of experimental noise in the reconstruction of both ϱ(p) and ϱ(k) are investigated. [ABSTRACT FROM AUTHOR]