A flexible, image-based, high-throughput platform encompassing in-depth cell profiling to identify broad-spectrum coronavirus antivirals with limited off-target effects.

The recent pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) posed a major threat to global health. Although the World Health Organization ended the public health emergency status, antiviral drugs are needed to address new variants of SARS-CoV-2 and future pandemics. To identify novel broad-spectrum coronavirus drugs, we developed a high-content imaging platform compatible with high-throughput screening. The platform is broadly applicable as it can be adapted to include various cell types, viruses, antibodies, and dyes. We demonstrated that the antiviral activity of compounds against SARS-CoV-2 variants (Omicron BA.5 and Omicron XBB.1.5), SARS-CoV, and human coronavirus 229E could easily be assessed. The inclusion of cellular dyes and immunostaining in combination with in-depth image analysis enabled us to identify compounds that induced undesirable phenotypes in host cells, such as changes in cell morphology or in lysosomal activity. With the platform, we screened ∼900K compounds and triaged hits, thereby identifying potential candidate compounds carrying broad-spectrum activity with limited off-target effects. The flexibility and early-stage identification of compounds with limited host cell effects provided by this high-content imaging platform can facilitate coronavirus drug discovery. We anticipate that its rapid deployability and fast turnaround can also be applied to combat future pandemics.

Adaptive quantization of local field potentials for wireless implants in freely moving animals: an open-source neural recording device.

OBJECTIVE: Modern neuroscience research requires electrophysiological recording of local field potentials (LFPs) in moving animals. Wireless transmission has the advantage of removing the wires between the animal and the recording equipment but is hampered by the large number of data to be sent at a relatively high rate. APPROACH: To reduce transmission bandwidth, we propose an encoder/decoder scheme based on adaptive non-uniform quantization. Our algorithm uses the current transmitted codeword to adapt the quantization intervals to changing statistics in LFP signals. It is thus backward adaptive and does not require the sending of side information. The computational complexity is low and similar at the encoder and decoder sides. These features allow for real-time signal recovery and facilitate hardware implementation with low-cost commercial microcontrollers. MAIN RESULTS: As proof-of-concept, we developed an open-source neural recording device called NeRD. The NeRD prototype digitally transmits eight channels encoded at 10 kHz with 2 bits per sample. It occupies a volume of 2 × 2 × 2 cm3 and weighs 8 g with a small battery allowing for 2 h 40 min of autonomy. The power dissipation is 59.4 mW for a communication range of 8 m and transmission losses below 0.1%. The small weight and low power consumption offer the possibility of mounting the entire device on the head of a rodent without resorting to a separate head-stage and battery backpack. The NeRD prototype is validated in recording LFPs in freely moving rats at 2 bits per sample while maintaining an acceptable signal-to-noise ratio (>30 dB) over a range of noisy channels. SIGNIFICANCE: Adaptive quantization in neural implants allows for lower transmission bandwidths while retaining high signal fidelity and preserving fundamental frequencies in LFPs.

Study of the scale formation mechanism on gold modified with an alkanethiol monolayer.

Scaling is a problem in many industrial processes. To control and minimize it, it is important to understand the dynamics of the scale formation. In this paper, the scale formation was examined on two kinds of gold surfaces. One was a pure metallic gold surface, and the other was a gold surface modified with an alkanethiol self-assembled monolayer. A series of surface characterization experiments were performed to ensure a good understanding of the gold-thiol bond stability in a caustic solution.

Adsorption enthalpy determination on silica-supported metallic nanoparticles.

A new specific method to measure adsorption enthalpy on supported metallic nanoparticles has been developed. This method is based on gas chromatography measurements, and it allows the calculation of adsorption enthalpies on metallic nanoparticles while neglecting the effect of the supporting particle. In this paper, we discuss the specific case of the adsorption of benzene on the surface of silica-supported gold nanoparticles. The results show a good correlation with similar values found in the literature.

Determination of the surface area of Pd and nanometric Au aggregates supported on a micrometric solid support by thiol adsorption and GC-MS.

A new sensitive and specific method to measure gold and palladium surface areas using alkanethiol adsorption coupled with analysis by gas chromatography with mass spectrometry detection has been developed. The effectiveness of the method was tested with metallic samples having a known surface area. The results have also been compared with BET specific surface area measurements. The results obtained with both methods show a good correlation.