Endothelial function assessment in atherosclerosis: Comparison of brachial artery flow‑mediated vasodilation and peripheral arterial tonometry

INTRODUCTION Endothelial dysfunction, characterized by the loss of nitric oxide bioavailability, is a key element in the pathogenesis of atherosclerosis and an important prognostic factor in cardiovascular diseases. Therefore, the development of reliable, safe, and noninvasive methods of endothelial function assessment is important for their use in cardiovascular risk stratification. Brachial artery flow‑mediated dilation (FMD) is widely used in research but technical difficulties and problems with calibration between laboratories limit its clinical use. Reactive hyperemia–peripheral artery tonometry (RH‑PAT, EndoPAT) has been developed as a simpler, cheaper, and potentially more reproducible method. OBJECTIVES We aimed to investigate associations between RH‑PAT and FMD in relation to atherosclerotic risk factor profile. PATIENTS AND METHODS The study involved 80 subjects (52 men, 28 women) aged 43.6 ±14.8 years, with moderate‑to‑low cardiovascular risk (mean SCORE, 2.2% ±2%), in whom FMD, RH‑PAT, and intima–media thickness (IMT) were determined. RESULTS The reactive hyperemia index (RHI) measured by RH‑PAT correlated with FMD (r = 0.35, P <0.01). However, no significant correlation was observed between RHI and IMT, SCORE, or the number of classical atherosclerotic risk factors (hypertension, smoking, diabetes, hypercholesterolemia), while FMD was significantly correlated with IMT (r = –0.53, P <0.001), risk factors (r = –0.55, P <0.05), and SCORE (r = –0.4, P <0.05). CONCLUSIONS Despite its technical requirements, FMD is a more sensitive method than RH‑PAT in evaluating the effect of classical atherosclerotic risk factors on vascular endothelial function. Microvasculature response during RH‑PAT needs to be further studied, including the assessment of nonendothelial factors that may affect the measurements, before RH‑PAT becomes the universal tool for the evaluation of the endothelial cells

Denture-related stomatitis is associated with endothelial dysfunction

Oral inflammation, such as periodontitis, can lead to endothelial dysfunction, accelerated atherosclerosis, and vascular dysfunction. The relationship between vascular dysfunction and other common forms of oral infections such as denture-related stomatitis (DRS) is unknown. Similar risk factors predispose to both conditions including smoking, diabetes, age, and obesity. Accordingly, we aimed to investigate endothelial function and major vascular disease risk factors in 44 consecutive patients with dentures with clinical and microbiological features of DRS (n = 20) and without DRS (n = 24). While there was a tendency for higher occurrence of diabetes and smoking, groups did not differ significantly in respect to major vascular disease risk factors. Groups did not differ in main ambulatory blood pressure, total cholesterol, or even CRP. Importantly, flow mediated dilatation (FMD) was significantly lower in DRS than in non-DRS subjects, while nitroglycerin induced vasorelaxation (NMD) or intima-media thickness (IMT) was similar. Interestingly, while triglyceride levels were normal in both groups, they were higher in DRS subjects, although they did not correlate with either FMD or NMD. Conclusions. Denture related stomatitis is associated with endothelial dysfunction in elderly patients with dentures. This is in part related to the fact that diabetes and smoking increase risk of both DRS and cardiovascular disease

Novel lines of Pax6-/- embryonic stem cells exhibit reduced neurogenic capacity without loss of viability

<p>Abstract</p> <p>Background</p> <p>Embryonic stem (ES) cells can differentiate into all cell types and have been used extensively to study factors affecting neuronal differentiation. ES cells containing mutations in known genes have the potential to provide useful in vitro models for the study of gene function during neuronal differentiation. Recently, mouse ES cell lines lacking the neurogenic transcription factor Pax6 were reported; neurons derived from these <it>Pax6</it>^-/-ES cells died rapidly after neuronal differentiation in vitro.</p> <p>Results</p> <p>Here we report the derivation of new lines of <it>Pax6</it>^-/-ES cells and the assessment of their ability to survive and differentiate both in vitro and in vivo. Neurons derived from our new <it>Pax6</it>^-/-lines were viable and continued to elaborate processes in culture under conditions that resulted in the death of neurons derived from previously reported <it>Pax6</it>^-/-ES cell lines. The new lines of <it>Pax6</it>^-/-ES cells showed reduced neurogenic potential, mimicking the effects of loss of Pax6 in vivo. We used our new lines to generate <it>Pax6</it>^-/-↔ <it>Pax6</it>^+/+chimeras in which the mutant cells survived and displayed the same phenotypes as <it>Pax6</it>^-/-cells in <it>Pax6</it>^-/-↔ <it>Pax6</it>^+/+chimeras made by embryo aggregation.</p> <p>Conclusions</p> <p>We suggest that loss of Pax6 from ES cells reduces their neurogenic capacity but does not necessarily result in the death of derived neurons. We offer these new lines as additional tools for those interested in the generation of chimeras and the analysis of in vitro ES cell models of Pax6 function during neuronal differentiation, embryonic and postnatal development.</p

Automated four-dimensional long term imaging enables single cell tracking within organotypic brain slices to study neurodevelopment and degeneration.

Current approaches for dynamic profiling of single cells rely on dissociated cultures, which lack important biological features existing in tissues. Organotypic slice cultures preserve aspects of structural and synaptic organisation within the brain and are amenable to microscopy, but established techniques are not well adapted for high throughput or longitudinal single cell analysis. Here we developed a custom-built, automated confocal imaging platform, with improved organotypic slice culture and maintenance. The approach enables fully automated image acquisition and four-dimensional tracking of morphological changes within individual cells in organotypic cultures from rodent and human primary tissues for at least 3 weeks. To validate this system, we analysed neurons expressing a disease-associated version of huntingtin (HTT586Q138-EGFP), and observed that they displayed hallmarks of Huntington's disease and died sooner than controls. By facilitating longitudinal single-cell analyses of neuronal physiology, our system bridges scales necessary to attain statistical power to detect developmental and disease phenotypes

Dissecting cellular diversity of cortical GABAergic cells across multiple modalities: A turning point in neuronal taxonomy

Decoding the complexity of the brain requires an understanding of the architecture, function, and development of its neuronal circuits. Neuronal classifications that group neurons based on specific features/behaviors have become essential to further analyze the different subtypes in a systematic and reproducible way. A comprehensive taxonomic framework, accounting for multiple defining and quantitative features, will provide the reference to infer generalized rules for cells ascribed to the same neuronal type, and eventually predict cellular behaviors, even in the absence of experimental measures. Technologies that enable cell-type classification in the nervous system are rapidly evolving in scalability and resolution. While these approaches depict astonishing diversity in neuronal morphology, electrophysiology, and gene expression, a robust metric of the coherence between different profiling modalities leading to a unified classification is still largely missing. Focusing on GABAergic neurons of the cerebral cortex, Gouwens et al.1 pioneered the first integrated cell-type classification based on the simultaneous analysis of the transcriptional networks, the recording of intrinsic electrophysiological properties, and the reconstruction of 3D morphologies of the same cell. Their comprehensive and high-quality data provide a new framework to shed light on what may be considered a "neuronal cell type.

Single-cell analysis of long non-coding RNAs in the developing human neocortex

Single cell transcriptomics of lncRNA expression in K562 cell cultures. A Distributions of median lncRNA expression to median mRNA expression ratios (lncRNA:mRNA) in populations, in silico merged single cells, and single cells from K562 cultures. B Proportion of K562 cells that expressed each lncRNA (blue) and mRNA (red), separated by maximum expression in single cells. C Same as in (B) but grouped by maximum expression quantile. D Distributions of non-zero lncRNA (blue) and mRNA (red) expression in 46 single K562 cells. Green squares, housekeeping genes; black triangles, ERCC Spike-In Controls. (PDF 454 kb

Winter Bird Assemblages in Rural and Urban Environments: A National Survey

Urban development has a marked effect on the ecological and behavioural traits of many living organisms, including birds. In this paper, we analysed differences in the numbers of wintering birds between rural and urban areas in Poland. We also analysed species richness and abundance in relation to longitude, latitude, human population size, and landscape structure. All these parameters were analysed using modern statistical techniques incorporating species detectability. We counted birds in 156 squares (0.25 km2 each) in December 2012 and again in January 2013 in locations in and around 26 urban areas across Poland (in each urban area we surveyed 3 squares and 3 squares in nearby rural areas). The influence of twelve potential environmental variables on species abundance and richness was assessed with Generalized Linear Mixed Models, Principal Components and Detrended Correspondence Analyses. Totals of 72 bird species and 89,710 individual birds were recorded in this study. On average (±SE) 13.3 ± 0.3 species and 288 ± 14 individuals were recorded in each square in each survey. A formal comparison of rural and urban areas revealed that 27 species had a significant preference; 17 to rural areas and 10 to urban areas. Moreover, overall abundance in urban areas was more than double that of rural areas. There was almost a complete separation of rural and urban bird communities. Significantly more birds and more bird species were recorded in January compared to December. We conclude that differences between rural and urban areas in terms of winter conditions and the availability of resources are reflected in different bird communities in the two environments

Neuroserpin expression during human brain development and in adult brain revealed by immunohistochemistry and single cell RNA sequencing

Neuroserpin is a serine‐protease inhibitor mainly expressed in the CNS and involved in the inhibition of the proteolytic cascade. Animal models confirmed its neuroprotective role in perinatal hypoxia‐ischaemia and adult stroke. Although neuroserpin may be a potential therapeutic target in the treatment of the aforementioned conditions, there is still no information in the literature on its distribution during human brain development. The present study provides a detailed description of the changing spatiotemporal patterns of neuroserpin focusing on physiological human brain development. Five stages were distinguished within our examined age range which spanned from the 7th gestational week until adulthood. In particular, subplate and deep cortical plate neurons were identified as the main sources of neuroserpin production between the 25th gestational week and the first postnatal month. Our immunohistochemical findings were substantiated by single cell RNA sequencing data showing specific neuronal and glial cell types expressing neuroserpin. The characterization of neuroserpin expression during physiological human brain development is essential for forthcoming studies which will explore its involvement in pathological conditions, such as perinatal hypoxia‐ischaemia and adult stroke in human