An Intersectional Exploration of Outness, Encountered Discrimination and Violence, and Non-Suicidal Self-Injury among Asexual Youth across Gender Identities.

Current research on asexual youth is limited, especially in understanding the impact of their outness and the intersection of sexual orientation with gender minority identities. This study investigates the influence of outness on experiences of harassment, discrimination, violence, and the risk of non-suicidal self-injury (NSSI) among asexual youth, with a focus on those with transgender and non-binary identities. Data for this study were obtained from the 2021 Ace Community Survey, an international online survey designed to assess the needs and health status of the Ace community, targeting respondents aged 13 and older. The analysis involved a subsample of 5574 respondents aged 13 to 24 (mean age = 19.28), including 2361 cisgender (mean age = 19.65), 1,195 transgender (mean age = 18.80), and 2,018 non-binary individuals (mean age = 19.13). The results revealed that experienceds of sexual violence, verbal aggression, and physical harassment and bullying not only correlated with but also completely mediated the relationship between outness and NSSI. Asexual transgender youth experienced heightened levels of discrimination and NSSI but demonstrated notable resilience against the negative effects of identity disclosure, highlighting complex dynamics of vulnerability and protection within these communities.

Regulating Lars2 in mitochondria: A potential Alzheimer's therapy by inhibiting tau phosphorylation.

Driven by the scarcity of effective treatment options in clinical settings, the present study aimed to identify a new potential target for Alzheimer's disease (AD) treatment. We focused on Lars2, an enzyme synthesizing mitochondrial leucyl-tRNA, and its role in maintaining mitochondrial function. Bioinformatics analysis of human brain transcriptome data revealed downregulation of Lars2 in AD patients compared to healthy controls. During in vitro experiments, the knockdown of Lars2 in mouse neuroblastoma cells (neuro-2a cells) and primary cortical neurons led to morphological changes and decreased density in mouse hippocampal neurons. To explore the underlying mechanisms, we investigated how downregulated Lars2 expression could impede the phosphatidylinositol 3-kinase/protein kinase B (PI3K-AKT) pathway, thereby mitigating AKT's inhibitory effect on glycogen synthase kinase 3 beta (GSK3ß). This led to the activation of GSK3ß, causing excessive phosphorylation of Tau protein and subsequent neuronal degeneration. During in vivo experiments, knockout of lars2 in hippocampal neurons confirmed cognitive impairment through the Barnes maze test, the novel object recognition test, and nest-building experiments. Additionally, immunofluorescence assays indicated an increase in p-tau, atrophy in the hippocampal region, and a decrease in neurons following Lars2 knockout. Taken together, our findings indicate that Lars2 represents a promising therapeutic target for AD.

Lung regeneration: diverse cell types and the therapeutic potential.

Lung tissue has a certain regenerative ability and triggers repair procedures after injury. Under controllable conditions, lung tissue can restore normal structure and function. Disruptions in this process can lead to respiratory system failure and even death, causing substantial medical burden. The main types of respiratory diseases are chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and acute respiratory distress syndrome (ARDS). Multiple cells, such as lung epithelial cells, endothelial cells, fibroblasts, and immune cells, are involved in regulating the repair process after lung injury. Although the mechanism that regulates the process of lung repair has not been fully elucidated, clinical trials targeting different cells and signaling pathways have achieved some therapeutic effects in different respiratory diseases. In this review, we provide an overview of the cell type involved in the process of lung regeneration and repair, research models, and summarize molecular mechanisms involved in the regulation of lung regeneration and fibrosis. Moreover, we discuss the current clinical trials of stem cell therapy and pharmacological strategies for COPD, IPF, and ARDS treatment. This review provides a reference for further research on the molecular and cellular mechanisms of lung regeneration, drug development, and clinical trials.

New dammarane-type triterpenoids from the whole plant of Euphorbia hypericifolia.

Euphorhypenoids A (1) and B (2), two new dammarane-type triterpenoids, along with four known tetracyclic triterpenoids (3-6), were isolated from the whole plant of Euphorbia hypericifolia. The structures of new compounds were mainly elucidated by a series of extensive spectroscopic methods, including HR-ESI-MS, NMR, IR, and UV. Compound 1 exhibited significant inhibitory effect on platelet aggregation at concentrations of 10 - 200 µM.

Single-cell transcriptome analysis reveals tumoral microenvironment heterogenicity and hypervascularization in human carotid body tumor.

Carotid body tumor (CBT) is a rare neck tumor located at the adventitia of the common carotid artery bifurcation. The prominent pathological features of CBT are high vascularization and abnormal proliferation. However, single-cell transcriptome analysis of the microenvironment composition and molecular complexity in CBT has yet to be performed. In this study, we performed single-cell RNA sequencing (scRNA-seq) analysis on human CBT to define the cells that contribute to hypervascularization and chronic hyperplasia. Unbiased clustering analysis of transcriptional profiles identified 16 distinct cell populations including endothelial cells (ECs), smooth muscle cells (SMCs), neuron cells, macrophage cells, neutrophil cells, and T cells. Within the ECs population, we defined subsets with angiogenic capacity plus clear signs of later endothelial progenitor cells (EPCs) to normal ECs. Two populations of macrophages were detectable in CBT, macrophage1 showed enrichment in hypoxia-inducible factor-1 (HIF-1) and as well as an early EPCs cell-like population expressing CD14 and vascular endothelial growth factor. In addition to HIF-1-related transcriptional protein expression, macrophages1 also display a neovasculogenesis-promoting phenotype. SMCs included three populations showing platelet-derived growth factor receptor beta and vimentin expression, indicative of a cancer-associated fibroblast phenotype. Finally, we identified three types of neuronal cells, including chief cells and sustentacular cells, and elucidated their distinct roles in the pathogenesis of CBT and abnormal proliferation of tumors. Overall, our study provided the first comprehensive characterization of the transcriptional landscape of CBT at scRNA-seq profiles, providing novel insights into the mechanisms underlying its formation.

Mitochondrial Regulation of Macrophages in Innate Immunity and Diverse Roles of Macrophages During Cochlear Inflammation.

Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation. Mitochondria regulate macrophage activation and innate immune responses in various inflammatory diseases, including cochlear inflammation. The distribution, number, and morphological characteristics of cochlear macrophages change significantly across different inner ear regions under various pathological conditions, including noise exposure, ototoxicity, and age-related degeneration. However, the exact mechanism underlying the role of mitochondria in macrophages in auditory function remains unclear. Here, we summarize the major factors and mitochondrial signaling pathways (e.g., metabolism, mitochondrial reactive oxygen species, mitochondrial DNA, and the inflammasome) that influence macrophage activation in the innate immune response. In particular, we focus on the properties of cochlear macrophages, activated signaling pathways, and the secretion of inflammatory cytokines after acoustic injury. We hope this review will provide new perspectives and a basis for future research on cochlear inflammation.

The role of cGAS-STING signaling in pulmonary fibrosis and its therapeutic potential.

Pulmonary fibrosis is a progressive and ultimately fatal lung disease, exhibiting the excessive production of extracellular matrix and aberrant activation of fibroblast. While Pirfenidone and Nintedanib are FDA-approved drugs that can slow down the progression of pulmonary fibrosis, they are unable to reverse the disease. Therefore, there is an urgent demand to develop more efficient therapeutic approaches for pulmonary fibrosis. The intracellular DNA sensor called cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) synthase (cGAS) plays a crucial role in detecting DNA and generating cGAMP, a second messenger. Subsequently, cGAMP triggers the activation of stimulator of interferon genes (STING), initiating a signaling cascade that leads to the stimulation of type I interferons and other signaling molecules involved in immune responses. Recent studies have highlighted the involvement of aberrant activation of cGAS-STING contributes to fibrotic lung diseases. This review aims to provide a comprehensive summary of the current knowledge regarding the role of cGAS-STING pathway in pulmonary fibrosis. Moreover, we discuss the potential therapeutic implications of targeting the cGAS-STING pathway, including the utilization of inhibitors of cGAS and STING.

An overview of limonoid synthetic derivatives as promising bioactive molecules.

Limonoids, a class of abundant natural tetracyclic triterpenoids, present diverse biological activity and provide a versatile platform amenable by chemical modifications for clinical use. Among all of the limonoids isolated from natural sources, obacunone, nomilin, and limonin are the primary hub of limonoid-based chemical modification research. To date, more than 800 limonoids analogs have been synthesized, some of which possess promising biological activities. This review not only discusses the synthesis of limonoid derivatives as promising therapeutic candidates and details the pharmacological studies of their underlying mechanisms from 2002 to 2022, but also proposes a preliminary limonoid synthetic structure-activity relationship (SAR) and provides future direction of limonoid derivatization research.

Biomarkers of aging.

Aging biomarkers are a combination of biological parameters to (i) assess age-related changes, (ii) track the physiological aging process, and (iii) predict the transition into a pathological status. Although a broad spectrum of aging biomarkers has been developed, their potential uses and limitations remain poorly characterized. An immediate goal of biomarkers is to help us answer the following three fundamental questions in aging research: How old are we? Why do we get old? And how can we age slower? This review aims to address this need. Here, we summarize our current knowledge of biomarkers developed for cellular, organ, and organismal levels of aging, comprising six pillars: physiological characteristics, medical imaging, histological features, cellular alterations, molecular changes, and secretory factors. To fulfill all these requisites, we propose that aging biomarkers should qualify for being specific, systemic, and clinically relevant.

Comprehensive Review of the Vascular Niche in Regulating Organ Regeneration and Fibrosis.

The vasculature occupies a large area of the body, and none of the physiological activities can be carried out without blood vessels. Blood vessels are not just passive conduits and barriers for delivering blood and nutrients. Meanwhile, endothelial cells covering the vascular lumen establish vascular niches by deploying some growth factors, known as angiocrine factors, and actively participate in the regulation of a variety of physiological processes, such as organ regeneration and fibrosis and the occurrence and development of cancer. After organ injury, vascular endothelial cells regulate the repair process by secreting various angiocrine factors, triggering the proliferation and differentiation process of stem cells. Therefore, analyzing the vascular niche and exploring the factors that maintain vascular homeostasis can provide strong theoretical support for clinical treatment targeting blood vessels. Here we mainly discuss the regulatory mechanisms of the vascular niche in organ regeneration and fibrosis.

DDX18 prevents R-loop-induced DNA damage and genome instability via PARP-1.

R loops occur frequently in genomes and contribute to fundamental biological processes at multiple levels. Consequently, understanding the molecular and cellular biology of R loops has become an emerging area of research. Here, it is shown that poly(ADP-ribose) polymerase-1 (PARP-1) can mediate the association of DDX18, a putative RNA helicase, with R loops thereby modulating R-loop homeostasis in endogenous R-loop-prone and DNA lesion regions. DDX18 depletion results in aberrant endogenous R-loop accumulation, which leads to DNA-replication defects. In addition, DDX18 depletion renders cells more sensitive to DNA-damaging agents and reduces RPA32 and RAD51 foci formation in response to irradiation. Notably, DDX18 depletion leads to γH2AX accumulation and genome instability, and RNase H1 overexpression rescues all the DNA-repair defects caused by DDX18 depletion. Taken together, these studies uncover a function of DDX18 in R-loop-mediated events and suggest a role for PARP-1 in mediating the binding of specific DDX-family proteins with R loops in cells.

Dioxane Bridge Formation during the Biosynthesis of Spectinomycin Involves a Twitch Radical S-Adenosyl Methionine Dehydrogenase That May Have Evolved from an Epimerase.

Spectinomycin is a dioxane-bridged, tricyclic aminoglycoside produced by Streptomyces spectabilis ATCC 27741. While the spe biosynthetic gene cluster for spectinomycin has been reported, the chemistry underlying construction of the dioxane ring is unknown. The twitch radical SAM enzyme SpeY from the spe cluster is shown here to catalyze dehydrogenation of the C2' alcohol of (2'R,3'S)-tetrahydrospectinomycin to yield (3'S)-dihydrospectinomycin as a likely biosynthetic intermediate. This reaction is radical-mediated and initiated via H atom abstraction from C2' of the substrate by the 5'-deoxyadenosyl radical equivalent generated upon reductive cleavage of SAM. Crystallographic analysis of the ternary Michaelis complex places serine-183 adjacent to C2' of the bound substrate opposite C5' of SAM. Mutation of this residue to cysteine converts SpeY to the corresponding C2' epimerase mirroring the opposite phenomenon observed in the homologous twitch radical SAM epimerase HygY from the hygromycin B biosynthetic pathway. Phylogenetic analysis suggests a relatively recent evolutionary branching of putative twitch radical SAM epimerases bearing homologous cysteine residues to generate the SpeY clade of enzymes.

Myocardial Segmentation of Cardiac MRI Sequences With Temporal Consistency for Coronary Artery Disease Diagnosis.

Coronary artery disease (CAD) is the most common cause of death globally, and its diagnosis is usually based on manual myocardial (MYO) segmentation of MRI sequences. As manual segmentation is tedious, time-consuming, and with low replicability, automatic MYO segmentation using machine learning techniques has been widely explored recently. However, almost all the existing methods treat the input MRI sequences independently, which fails to capture the temporal information between sequences, e.g., the shape and location information of the myocardium in sequences along time. In this article, we propose a MYO segmentation framework for sequence of cardiac MRI (CMR) scanning images of the left ventricular (LV) cavity, right ventricular (RV) cavity, and myocardium. Specifically, we propose to combine conventional neural networks and recurrent neural networks to incorporate temporal information between sequences to ensure temporal consistency. We evaluated our framework on the automated cardiac diagnosis challenge (ACDC) dataset. The experiment results demonstrate that our framework can improve the segmentation accuracy by up to 2% in the Dice coefficient.

Dopamine receptor D2 antagonism normalizes profibrotic macrophage-endothelial crosstalk in non-alcoholic steatohepatitis.

BACKGROUND & AIMS: Currently there is no effective treatment for liver fibrosis, which is one of the main histological determinants of non-alcoholic steatohepatitis (NASH). While Hippo/YAP (Yes-associated protein) signaling is essential for liver regeneration, its aberrant activation frequently leads to fibrosis and tumorigenesis. Unravelling "context-specific" contributions of YAP in liver repair might help selectively bypass fibrosis and preserve the pro-regenerative YAP function in hepatic diseases. METHODS: We used murine liver fibrosis and minipig NASH models, and liver biopsies from patients with cirrhosis. Single-cell RNA-sequencing (scRNA-Seq) was performed, and a G-protein-coupled receptor (GPCR) ligand screening system was used to identify cell-selective YAP inhibitors. RESULTS: YAP levels in macrophages are increased in the livers of humans and mice with liver fibrosis. The increase in type I interferon and attenuation of hepatic fibrosis observed in mice specifically lacking Yap1 in myeloid cells provided further evidence for the fibrogenic role of macrophage YAP. ScRNA-Seq further showed that defective YAP pathway signaling in macrophages diminished a fibrogenic vascular endothelial cell subset that exhibited profibrotic molecular signatures such as angiocrine CTGF and VCAM1 expression. To specifically target fibrogenic YAP in macrophages, we utilized a GPCR ligand screening system and identified a dopamine receptor D2 (DRD2) antagonist that selectively blocked YAP in macrophages but not hepatocytes. Genetic and pharmacological targeting of macrophage DRD2 attenuated liver fibrosis. In a large animal (minipig) NASH model recapitulating human pathology, the DRD2 antagonist blocked fibrosis and restored hepatic architecture. CONCLUSIONS: DRD2 antagonism selectively targets YAP-dependent fibrogenic crosstalk between macrophages and CTGF+VCAM1+ vascular niche, promoting liver regeneration over fibrosis in both rodent and large animal models. LAY SUMMARY: Fibrosis in the liver is one of the main histological determinants of non-alcoholic steatohepatitis (NASH), a disease paralleling a worldwide surge in metabolic syndromes. Our study demonstrates that a macrophage-specific deficiency in Yes-associated protein (YAP) attenuates liver fibrosis. Dopamine receptor D2 (DRD2) antagonism selectively blocks YAP in macrophages and thwarts liver fibrosis in both rodent and large animal models, and thus holds potential for the treatment of NASH.

Targeting epigenetically maladapted vascular niche alleviates liver fibrosis in nonalcoholic steatohepatitis.

Chronic hepatic diseases such as nonalcoholic steatohepatitis (NASH) suppress liver regeneration and lead to fibrosis and cirrhosis. Decoding the cellular and molecular network underlying this fibrotic maladaptation might aid in combatting NASH, a growing health challenge with no approved therapies. Here, we used multiomics analysis of human cirrhotic liver, a Western diet­ and carbon tetrachloride (CCl4)­induced minipig NASH model, and genetically modified mice to unravel the landscape of the vascular adaptome at the single-cell level, in which endothelial cells (ECs) and TH17 cells jointly contribute to liver cirrhosis. We found that epigenetics-dependent hepatic vascular maladaptation enriches fibrogenic TH17 cells to promote liver fibrosis in mice, minipigs, and human patients with cirrhosis. Further analysis of humans, minipigs, and mice suggested that cross-talk between histone deacetylase 2 (HDAC2) and DNA methyltransferase 1 (DNMT1) promoted liver EC maladaptation to promote production of angiocrine IGFBP7 and ADAMTS1 in extracellular vesicles, recruiting fibrogenic TH17 cells to the liver. Pharmacological targeting of HDAC2 and DNMT1 alleviated fibrosis in a minipig NASH model. We conclude that epigenetically reprogrammed vascular adaptation contributes to liver fibrosis. Targeting of a vascular adaptation node might block maladaptive vascularization to promote liver regeneration in NASH.

Analysis of A1-type and A2-type ß-casein in Maiwa Yak and Pien-niu milk by HPLC-high-resolution MS and tandem MS.

In this study, a peptide-based method employing ultra high performance liquid chromatography electrostatic field orbitrap high-resolution mass spectrometry and triple quadrupole mass spectrometry was developed for quantification of A1-type and A2-type ß-casein in milk from Yak, cows, and their offspring of crosses, Pien-niu. The specific peptides of A1-type and A2-type ß-casein were screened and confirmed by protein software after analysis of high-resolution mass spectrometry. The multiple reaction monitoring method was established based on the qualitative results, and isotope-label peptides were used as internal standards. The linear correlation coefficients of this method were >0.99. The relative standard deviations of repeatability test were 0.2-3.6%. The recovery rate ranged from 93.3 to 114.4% with relative standard deviations <6% at three different spiking levels. The method was applied to analyze 45 milk samples from different species. The results showed that ß-casein in Yak and Pien-niu milk was about 30% higher than that in cow milk. Furthermore, the ß-casein in the Yak milk only contains A2-type ß-casein. A1-type and A2-type ß-casein coexist in most samples of Pien-niu and cow milk, a few samples contain only one type of ß-casein. These results provide further understanding in nutritional value of milk from Yak and Pien-niu.

Aging Reprograms the Hematopoietic-Vascular Niche to Impede Regeneration and Promote Fibrosis.

Regenerative capacity is frequently impaired in aged organs. Stress to aged organs often causes scar formation (fibrosis) at the expense of regeneration. It remains to be defined how hematopoietic and vascular cells contribute to aging-induced regeneration to fibrotic transition. Here, we find that aging aberrantly reprograms the crosstalk between hematopoietic and vascular cells to impede the regenerative capacity and enhance fibrosis. In aged lung, liver, and kidney, induction of Neuropilin-1/hypoxia-inducible-factor 2α (HIF2α) suppresses anti-thrombotic and anti-inflammatory endothelial protein C receptor (EPCR) pathway, leading to formation of pro-fibrotic platelet-macrophage rosette. Activated platelets via supplying interleukin 1α synergize with endothelial-produced angiocrine chemokine to recruit fibrogenic TIMP1high macrophages. In mouse models, genetic targeting of endothelial Neuropilin-1-HIF2α, platelet interleukin 1α, or macrophage TIMP1 normalized the pro-fibrotic hematopoietic-vascular niche and restored the regenerative capacity of old organs. Targeting of aberrant endothelial node molecules might help propel "regeneration without scarring" in the repair of multiple organs.

Linkage, recombination, and mutation rate analyses of 19 X-chromosomal STR loci in Chinese Southern Han pedigrees.

From Southern Han Chinese samples, we analyzed 19 X-STR markers for linkage, linkage disequilibrium (LD), and mutation rate. The data were collected from two- and three-generation Southern Han Chinese families. These data suggested that both linkage and linkage disequilibrium should be considered while calculating likelihood ratios with X-STR markers in relationship tests. The linkage disequilibrium of these 19 X-STR markers was calculated in our previous research study that was conducted on Southern Han Chinese population. In this study, the recombination fractions between pairs of markers and those obtained from the second-generation Rutgers combined linkage-physical map of the human genome were compared. The observed differences indicated that recombination was not homogeneous along the X chromosome. Therefore, we evaluated the effect on likelihood calculations by referring to haplotype frequencies obtained from allele distributions rather than haplotype counts of Southern Han Chinese population.

Mastering the game of Go without human knowledge.

A long-standing goal of artificial intelligence is an algorithm that learns, tabula rasa, superhuman proficiency in challenging domains. Recently, AlphaGo became the first program to defeat a world champion in the game of Go. The tree search in AlphaGo evaluated positions and selected moves using deep neural networks. These neural networks were trained by supervised learning from human expert moves, and by reinforcement learning from self-play. Here we introduce an algorithm based solely on reinforcement learning, without human data, guidance or domain knowledge beyond game rules. AlphaGo becomes its own teacher: a neural network is trained to predict AlphaGo's own move selections and also the winner of AlphaGo's games. This neural network improves the strength of the tree search, resulting in higher quality move selection and stronger self-play in the next iteration. Starting tabula rasa, our new program AlphaGo Zero achieved superhuman performance, winning 100-0 against the previously published, champion-defeating AlphaGo.

Targeting the vascular and perivascular niches as a regenerative therapy for lung and liver fibrosis.

The regenerative capacity of lung and liver is sometimes impaired by chronic or overwhelming injury. Orthotopic transplantation of parenchymal stem cells to damaged organs might reinstate their self-repair ability. However, parenchymal cell engraftment is frequently hampered by the microenvironment in diseased recipient organs. We show that targeting both the vascular niche and perivascular fibroblasts establishes "hospitable soil" to foster the incorporation of "seed," in this case, the engraftment of parenchymal cells in injured organs. Specifically, ectopic induction of endothelial cell (EC)-expressed paracrine/angiocrine hepatocyte growth factor (HGF) and inhibition of perivascular NOX4 [NADPH (reduced form of nicotinamide adenine dinucleotide phosphate) oxidase 4] synergistically enabled reconstitution of mouse and human parenchymal cells in damaged organs. Reciprocally, genetic knockout of Hgf in mouse ECs (HgfiΔEC/iΔEC) aberrantly up-regulated perivascular NOX4 during liver and lung regeneration. Dysregulated HGF and NOX4 pathways subverted the function of vascular and perivascular cells from an epithelially inductive niche to a microenvironment that inhibited parenchymal reconstitution. Perivascular NOX4 induction in HgfiΔEC/iΔEC mice recapitulated the phenotype of human and mouse liver and lung fibrosis. Consequently, EC-directed HGF and NOX4 inhibitor GKT137831 stimulated regenerative integration of mouse and human parenchymal cells in chronically injured lung and liver. Our data suggest that targeting dysfunctional perivascular and vascular cells in diseased organs can bypass fibrosis and enable reparative cell engraftment to reinstate lung and liver regeneration.