Variable-Volume Engine

A description is given of an engine using the expansion-contraction of bodies subjected to controlled thermal variations and making use of free natural heat sources

Antiretroviral effect of lovastatin on HIV-1-infected individuals without highly active antiretroviral therapy (The LIVE study): a phase-II randomized clinical trial

<p>Abstract</p> <p>Background</p> <p>Highly active antiretroviral therapy produces a significant decrease in HIV-1 replication and allows an increase in the CD4 T-cell count, leading to a decrease in the incidence of opportunistic infections and mortality. However, the cost, side effects and complexity of antiretroviral regimens have underscored the immediate need for additional therapeutic approaches. Statins exert pleiotropic effects through a variety of mechanisms, among which there are several immunoregulatory effects, related and unrelated to their cholesterol-lowering activity that can be useful to control HIV-1 infection.</p> <p>Methods/design</p> <p>Randomized, double-blinded, placebo controlled, single-center, phase-II clinical trial. One hundred and ten chronically HIV-1-infected patients, older than 18 years and naïve for antirretroviral therapy (i.e., without prior or current management with antiretroviral drugs) will be enrolled at the outpatient services from the most important centres for health insurance care in Medellin-Colombia. The interventions will be lovastatin (40 mg/day, orally, for 12 months; 55 patients) or placebo (55 patients). Our primary aim will be to determine the effect of lovastatin on viral replication. The secondary aim will be to determine the effect of lovastatin on CD4+ T-cell count in peripheral blood. As tertiary aims we will explore differences in CD8+ T-cell count, expression of activation markers (CD38 and HLA-DR) on CD4 and CD8 T cells, cholesterol metabolism, LFA-1/ICAM-1 function, Rho GTPases function and clinical evolution between treated and not treated HIV-1-infected individuals.</p> <p>Discussion</p> <p>Preliminary descriptive studies have suggested that statins (lovastatin) may have anti HIV-1 activity and that their administration is safe, with the potential effect of controlling HIV-1 replication in chronically infected individuals who had not received antiretroviral medications. Considering that there is limited clinical data available on this topic, all these findings warrant further evaluation to determine if long-term administration of statins may benefit the virological and immunological evolution in HIV-1-infected individuals before the use of antiretroviral therapy is required.</p> <p>Trial registration</p> <p>Registration number NCT00721305.</p

Pneumatic evoked potential. Sensory or auditive potential?

International audienceIn this study, evoked potentials (EPs) to a pneumatic, innocuous, and calibrated stimulation of the skin were recorded in 22 volunteers. A reproducible EP was recorded in 18 out of 22 subjects (82% of cases) with a mean latency of about 120-130 ms, and maximal amplitude at Cz. This EP actually consisted of two components, an auditory and a somatosensory one. Indeed, it was significantly decreased in amplitude, but did not disappear, when the noise generated by the air-puff was masked. We also verified that a stimulation close to the skin but not perceived by the subject was not associated with any EP. Conduction velocity between hand and shoulder was calculated around 25 m/s. This preliminary study demonstrates that pneumatic EPs can be recorded in normal volunteers

The morphology of tin cluster assembled films and the effect of nitrogen

Thin films produced by depositing tin clusters with sizes between 5 and 10 nm onto silicon nitride substrates were found to be highly coalesced resulting in grains with sizes ~30 nm. Exposing the clusters to nitrogen before they were deposited significantly reduced the coalescence between them and resulted in granular films where the clusters mostly retained their shape. This is due to a small amount of tin nitride forming in the clusters. The coalesced and granular films were used to fabricate tin oxide gas sensors. This was done by depositing the two types of films onto silicon nitride chips and then oxidising them by baking at 250 °C for 24 h. It was found that the sensors composed of uncoalesced clusters were much more sensitive to hydrogen. This was attributed to the smaller grain size and the larger surface area of the granular films