Clinical Application of Epithelial Sodium Channel (ENaC) as a Biomarker for Arterial Hypertension.

Arterial hypertension (HTN) is a global public health concern and an important risk factor for cardiovascular diseases and renal failure. We previously reported overexpression of ENaC on the plasma membrane of human platelets is a hallmark of HTN. In this double-blinded study of an open population (n = 167), we evaluated the sensitivity and specificity of a diagnostic assay based on gold nanoparticles (AuNPs) conjugated to an antibody against epithelial sodium channel (ENaC) expressed on platelets, which is detected using a fluorescent anti-ENaC secondary antibody and spectrofluorometry. Using the cutoff value for the AuNP-anti-ENaC assay, we confirmed the diagnosis for 62.1% of patients with clinical HTN and detected 59.7% of patients had previously undiagnosed HTN. Although some shortcomings in terms of accurately discriminating healthy individuals and patients with HTN still need to be resolved, we propose this AuNP-anti-ENaC assay could be used for initial screening and early diagnosis to critically improve opportune clinical management of HTN.

Oral Silica Nanoparticles Lack of Neurotoxic Effects in a Parkinson's Disease Model: A Possible Nanocarrier?

Silica nanoparticles (SiO2-NP) are an option as drug carriers due to their biodegradability, biocompatibility, and capacity to bind themselves to other compounds. However, until now, the effect of these particles on the brain when neurodegeneration occurs is unknown. Hence, this work focused on the in vivo evaluation of the neurotoxic effects of SiO2-NP when oxidative and inflammation are present during the development of Parkinson's disease. To determine whether SiO2-NP may act as a non-neurotoxic carrier we evaluated if the intragastric administration (ig) of SiO2-NP of 150 nm (25, 50 and 100 mg/kg administered for five consecutive days) increased neuronal damage induced with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration. SiO2-NP administration did not further decrease cell viability assessed by MTT reduction, nor increased lipid peroxidation measured by TBARS or TNF α levels in the striatum and the substantia nigra in the MPTP model. Furthermore, we observed no additional reduction in striatal dopamine levels. The present results suggest that SiO2-NP of 150 nm are suitable nanocarrier for Parkinson's disease drugs without generating any additional damage.

The Influence of the External Signal Modulation Waveform and Frequency on the Performance of a Photonic Forced Oscillator.

Photonic crystals have been an object of interest because of their properties to inhibit certain wavelengths and allow the transmission of others. Using these properties, we designed a photonic structure known as photodyne formed by two porous silicon one-dimensional photonic crystals with an air defect between them. When the photodyne is illuminated with appropriate light, it allows us to generate electromagnetic forces within the structure that can be maximized if the light becomes localized inside the defect region. These electromagnetic forces allow the microcavity to oscillate mechanically. In the experiment, a chopper was driven by a signal generator to modulate the laser light that was used. The driven frequency and the signal modulation waveform (rectangular, sinusoidal or triangular) were changed with the idea to find optimal conditions for the structure to oscillate. The microcavity displacement amplitude, velocity amplitude and Fourier spectrum of the latter and its frequency were measured by means of a vibrometer. The mechanical oscillations are modeled and compared with the experimental results and show good agreement. For external frequency values of 5 Hz and 10 Hz, the best option was a sinusoidal waveform, which gave higher photodyne displacements and velocity amplitudes. Nonetheless, for an external frequency of 15 Hz, the best option was the rectangular waveform.