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Europe can capture the US brain drain — if it acts fast
Bioinformatics prediction of function of T-cell exhaustion related genes in ischemic stroke
Mid-infrared acetone gas sensors using substrate-integrated hollow waveguides augmented by advanced preconcentrators
Abstract The identification of volatile organic compounds (VOC) such as acetone, a relevant biomarker for diabetes mellitus in exhaled human breath has become essential for early disease diagnostics, prognosis, and monitoring of metabolic responses to pharmacological interventions. Gas chromatography coupled with mass spectrometry (GC–MS) is considered as the gold standard for breath analysis. However, its inability to offer point-of-care monitoring limits its applicability in clinical environments. Optical techniques based on absorption in the mid-infrared range (2.5 to 25 μm) appear as promising alternatives due to their inherent selectivity, potential for miniaturization, portability, and direct analysis with rapid response. Relevant biomarkers present in exhaled breath, are usually observed in the ppb to ppm (v/v) concentration regime. For sensitivity enhancement of optical sensing techniques, appropriate preconcentration schemes are required prior to the optical detection. The present study describes a method combining a multi-channel substrate-integrated preconcentration module (a.k.a., muciPRECON) for enhancing and optimizing the detection of acetone via a mid-infrared photonic sensing system. The sensor system comprises a compact Fourier Transform Infrared (FTIR) spectrometer, a technique that enables detailed infrared spectral analysis, coupled to a substrate-integrated hollow waveguide (iHWG) simultaneously acting as a gas cell and as a photon conduit. Preconcentation experiments were from acetone/nitrogen gas mixtures in the concentration range of 5–100 ppm at − 10 °C followed by desorption at a temperature of 100 °C and direct injection into the IR sensing system Thus obtained acetone spectra were quantified evaluating a molecule-specific vibrational absorption peak area in the spectral window 1260–1170 cm−1. After extensive screening, Tenax was identified as superior sorbent material providing an enrichment factor of up to 153-times, a limit of detection (LOD) of 0.118 ppm, and a limit of quantification (LOQ) of 0.393 ppm. These results are indeed promising for practical applications, especially since acetone concentrations usually vary between 0.3 and 0.9 ppmv within the exhaled breath of healthy individuals, and in individuals with diabetes, acetone concentrations are typically around 1.7 to 3.0 ppmv. Consequently, the developed systems have the necessary sensitivity and accuracy to detect acetone levels that are in the relevant physiological range indicating their potential use in future real-world scenarios.
Advanced modeling of salt-inducible kinase (SIK) inhibitors incorporating protein flexibility through molecular dynamics and cross-docking
Multi-zonal liver organoids from human pluripotent stem cells
Changes in the distribution of elements in the liver and various brain regions in suicides from southeastern Poland
Abstract The anthropogenic environment and diet are sources of chemical elements, both essential and toxic. Many of them play a key role in the proper functioning of the brain by controlling oxidative metabolism, neurotransmission and the production of neurotransmitters. Disturbances in element homeostasis are associated with the development of depression and many neurodegenerative diseases. The study examined the content of several elements in liver and brain samples taken from autopsies of residents of south-eastern Poland (n = 40). In order to determine the differences in the elemental composition of tissues collected from suicide victims compared to the control group who died from another cause, the Mann-Whitney U test was performed. There was a significant difference in the correlation patterns between the two groups for both brain (χ² = 1490.19, df = 1378, p < 7e-122, z = 3.72) and liver χ² = 2998.7, df = 1378, p < 0.018, z = 126.71). Two-way non-parametric Spearman rank correlation matrices showed different numbers and strengths of correlations for most brain regions in the compared groups, especially for the head of the caudate nucleus (Latin: caput nuclei caudati), superior longitudinal fasciculus (Latin: fasciculus longitudinalis superior cerebri), and hippocampus (Latin: hippocampus). Differences between groups reached statistical significance in the case of higher lanthanide content in the liver of suicides and lower Ca content in the basal ganglia (head of the caudate nucleus, nucleus accumbens septum), dorsal thalamus and insula. Brain samples from different regions of suicide victims were characterized by higher levels of, among others: Ag, P, Fe and Cu. Our findings suggest clear differences in trace metal content and inter-correlations in the brain and liver tissues of suicide victims compared to controls.