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Considering the trans-cleavage capabilities, high-specificity and programmability, the CRISPR-Cas system has been recognized as a valuable platform to develop the next-generation diagnostic biosensors. However, due to the natural interaction with nucleic acids, current CRISPR-Cas-based detection mostly applies in nucleic acid analysis rather than non-nucleic acid analysis. By virtue of spherical nucleic acids (SNAs) with programmability and specificity, the Y-shaped DNA nanostructures assembled-SNAs (Y-SNAs) were rationally designed as target converters to achieve the quantitative activation of CRISPR-Cas12a, enabling a highly specific and sensitive electrochemiluminescence (ECL) determination of alpha-methylacyl-CoA racemase (AMACR), a high specific protein biomarker of prostate cancer. Significantly, the Y-shaped DNA nanostructures comprised of assisted DNA (A1), AMACR aptamer and DNA activator of CRISPR-Cas12a were loaded on Au nanoparticles modified Fe 3 O 4 magnetic beads (Au@Fe 3 O 4 MBs) to construct the robust Y-SNAs. In the presence of the target AMACR, the Y-SNAs as target converters could achieve quantitative activation of CRISPR-Cas12a by outputting the DNA activators with a linear relationship to the target. The amplified ECL signals were triggered by the release of the ferrocene-labeled quenching probes (QPs) on the electrode surface due to the trans-cleavage activity of CRISPR-Cas12a, thereby realizing the sensitive ECL determination of AMACR from 10 ng/mL to 100 μg/mL with the detection limit of 1.25 ng/mL. In general, this approach provides novel perspectives on how to design a universal ECL platform of the CRISPR-Cas system to detect the non-nucleic acid targets beyond the traditional methods., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Congenital central hypoventilation syndrome (CCHS) represents a rare genetic disorder usually caused by mutations in the homeodomain transcription factor PHOX2B. Some CCHS patients suffer mainly from deficiencies in CO 2 and/or O 2 respiratory chemoreflex, whereas other patients present with full apnea shortly after birth. Our goal was to identify the neuropathological mechanisms of apneic presentations in CCHS. In the developing murine neuroepithelium, Phox2b is expressed in three discrete progenitor domains across the dorsal-ventral axis, with different domains responsible for producing unique autonomic or visceral motor neurons. Restricting the expression of mutant Phox2b to the ventral visceral motor neuron domain induces marked newborn apnea together with a significant loss of visceral motor neurons, RTN ablation, and preBötzinger complex dysfunction. This finding suggests that the observed apnea develops through non-cell autonomous developmental mechanisms. Mutant Phox2b expression in dorsal rhombencephalic neurons did not generate significant respiratory dysfunction, but did result in subtle metabolic thermoregulatory deficiencies. We confirm the expression of a novel murine Phox2b splice variant which shares exons 1 and 2 with the more widely studied Phox2b splice variant, but which differs in exon 3 where most CCHS mutations occur. We also show that mutant Phox2b expression in the visceral motor neuron progenitor domain increases cell proliferation at the expense of visceral motor neuron development. We propose that visceral motor neurons may function as organizers of brainstem respiratory neuron development, and that disruptions in their development result in secondary/non-cell autonomous maldevelopment of key brainstem respiratory neurons., (© 2020 International Society of Neuropathology.)

The emergence of systems neuroscience tools requires parallel generation of objective analytical workflows for experimental neuropathology. We developed an objective analytical workflow that we used to determine how specific autonomic neural lineages change during postnatal development. While a wealth of knowledge exists regarding postnatal alterations in respiratory neural function, how these neural circuits change and develop in the weeks following birth remains less clear. In this study, we developed our workflow by combining genetic mouse modeling and quantitative immunofluorescent confocal microscopy and used this to examine the postnatal development of neural circuits derived from the transcription factors NKX2.2 and OLIG3 into three medullary respiratory nuclei. Our automated FIJI-based image analysis workflow rapidly and objectively quantified synaptic puncta in user-defined anatomic regions. Using our objective workflow, we found that the density and estimated total number of Nkx2.2-derived afferents into the pre-Bötzinger Complex significantly decreased with postnatal age during the first three weeks of postnatal life. These data indicate that Nkx2.2-derived structures differentially influence pre-Bötzinger Complex respiratory oscillations at different stages of postnatal development., (© 2018 Wiley Periodicals, Inc.)

To investigate the effect of mifepristone on gene expression of human chorionic villi in early pregnancy, nine women were recruited into a randomised controlled trial. All subjects were healthy women who had regular menstrual cycles and sought termination of pregnancy up to 40 days gestational age. In the test group, gestational sacs were taken by vacuum aspiration of the uterus 24 h after a single dose of 150 mg mifepristone was administered. Chorionic villi were collected and frozen in liquid nitrogen. The control samples were collected using the same method from the women without administration of mifepristone. The gene expressions of villus were monitored by human cDNA microarrays. It is found that the expressions of 262 transcripts were significantly altered in the test group. Gene ontology and pathways analyses were conducted to further analyse these genes. Many of these genes are known to play potentially an important role in the placentation and the molecular regulation of maternal-fetal interface. Therefore, it is suggested that the placental development and microenvironment of the maternal-fetal interface were interfered by administration of mifepristone. These data provide insight into the molecular mechanism about medical abortion induced by mifepristone.