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1 Cadmium is an extremely toxic metal commonly found in industrial workplaces, a food contaminant and a major component of cigarette smoke. Cadmium can severely damage several organs, including the brain. In this work, we have studied both the cadmium toxicity on rat cortical neurons in culture and the possible protective eect of serum. 2 Our results indicate that: (1) cadmium is taken up by the neurons in a dose and serum dependent way; (2) cadmium, at concentrations from 1 mM or 10 mM (depending on the absence or the presence of serum) up to 100 mM, decreases the metabolic capacity, which was evaluated by the XTT (tetrazolium salt) test; (3) cadmium induces apoptosis and LDH (lactate dehydrogenase) release in a dose dependent way; (4) in a serum-free medium, the cadmium-induced apoptosis is accompanied by caspase-3 activation; (5) both the caspase-3 activation and the cadmium-induced apoptosis are reversed by N-acethyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO), a selective caspase-3 inhibitor, indicating that the caspase-3 pathway is involved in cadmium-induced apoptosis in cortical neurons; and (6) the cadmium concentrations which produce caspase-3 activation do not modify the intracellular ATP levels; however, higher cadmium concentrations lead to both intracellular ATP depletion and ATP release, but do not increase the caspase-3 activity, indicating that cadmium also produces cellular death by necrosis. 3 These results suggest that cadmium induces either apoptosis or necrosis in rat cortical neurons, depending on the cadmium concentration.

Headline: Inhibition of pathogenic microbiota SUMMARYThe concrete nature of the probiotic effects that the presence of microorganisms (especially lactic acid bacteria: LAB) exercise on larval cultures of fish, it is not well defined, being been able to attribute to different factors or action mechanisms. In fact, the production of diverse antibacterial metabolites (bacteriocins in particular) by many LAB forms are able to constitute the basis of these probiotic effects, as repeatedly described in the literature. Accordingly, the inhibition of fish pathogenic species by extracts of LAB constitutes a rapid method for detecting potential probiotics. By studying the response of four common pathogens of turbot (Scophthalmus maximus) to nine potential probiotics, the diversity and mechanisms of effectors in the probiotics were demonstrated to present complex profiles dose-response and non-treatable with conventional models. Proposed modifications allow satisfactory fits and the calculation of useful parameters in the comparison of activities. The results showed that lactic and acetic acid, and not the bacteriocins, are responsible for effects (inhibitory or stimulatory depending on the concentrations considered) in all the cases studied.

We report the synthesis, theoretical calculations, the antioxidant, anti-inflammatory, and neuroprotective properties, and the ability to cross the blood–brain barrier (BBB) of (Z)-α-aryl and heteroaryl-N-alkyl nitrones as potential agents for stroke treatment. The majority of nitrones compete with DMSO for hydroxyl radicals, and most of them are potent lipoxygenase inhibitors. Cell viability-related (MTT assay) studies clearly showed that nitrones 1–3 and 10 give rise to significant neuroprotection. When compounds 1–11 were tested for necrotic cell death (LDH release test) nitrones 1–3, 6, 7, and 9 proved to be neuroprotective agents. In vitro evaluation of the BBB penetration of selected nitrones 1, 2, 10, and 11 using the PAMPA-BBB assay showed that all of them cross the BBB. Permeable quinoline nitrones 2 and 3 show potent combined antioxidant and neuroprotective properties and, therefore, can be considered as new lead compounds for further development in specific tests for potential stroke treatment.

A vortex lattice ratchet effect has been investigated in Nb films grown on arrays of nanometric Ni triangles, which induce periodic asymmetric pinning potentials. The vortex lattice motion yields a net dc voltage when an ac driving current is applied to the sample and the vortex lattice moves through the field of asymmetric potentials. This ratchet effect is studied taking into account the array geometry, the temperature, the number of vortices per unit cell of the array, and the applied ac currents. DOI: 10.1103/PhysRevB.71.024519 PACS number͑s͒: 74.78.Ϫw, 05.60.Ϫk, 74.40.ϩk Feynman used, in his Lectures on Physics, 1 a ratchet to show how anisotropy never could lead to net motion in an equilibrium system. Since then, asymmetric sawtooth potentials are called ratchet potentials and, in general, a device with broken inversion symmetry is called a ratchet device. The ratchet effect occurs when asymmetric potentials induce outward particle flow under external fluctuations in the lack of any driving direct outward forces. The ratchet effect changes an ac source in a dc one. Ratchet effect spans from Nature phenomena to laboratory fabricated devices. In a ratchet, the energy necessary for net motion is provided by raising and lowering the barriers and wells, either via an external time-dependent modulation, for example an ac current injected in a superconducting film with asymmetric pinning centers, 2 or by energy input from a nonequilibrium source, such as a chemical reaction, as for instance in biological motors. 3 During the past years, ratchet effect has called the attention of many researchers. A state of the art on the related topics Brownian motion and ratchet potential could be found in Ref. 4.The use of ratchetlike pinning potentials in superconductors has been the subject of theoretical approaches which deal with very different topics, for instance, to remove flux trapped in superconducting devices, 5 fluxon optic, 6 logic devices, 7 etc. From the experimental point of view, some progress has been reported related to superconducting circuits, [8][9][10] and very recently vortex motion ratchet effect has been reported in superconducting films with artificially fabricated arrays of asymmetric pinning centers. 2 In the present paper, we will address some of the properties of this superconducting ratchet effect. We will explore the dependence of the ratchet with the applied alternating current, the array shape, the temperature, and the number of vortices per array unit cell. We will show that periodic asymmetric potentials are crucial to produce the ratchet behavior, that the effect is enhanced decreasing the temperature, and finally, that the effect decreases when the applied magnetic field ͑number of vortices per unit cell of the array͒ increases. The paper is organized as follows: First, we will summarize some results on the behavior of vortex lattice on artificially induced pinning potentials. After this, we will present the fabrication method and main characteristics of the films. Finally, the experim...