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Pericytes are versatile cells integral to the blood vessel walls of the microcirculation, where they exhibit specific stem cell traits. They are essential in modulating blood flow, ensuring vascular permeability, and maintaining homeostasis and are involved in the tissue repair process. The human endometrium is a unique and complex tissue that serves as a natural scar-free healing model with its cyclical repair and regeneration process every month. The regulation of pericytes has gained increasing attention due to their involvement in various physiological and pathological processes. However, endometrial pericytes are less well studied compared to the pericytes in other organs. This review aims to provide a comprehensive overview of endometrial pericytes, with a focus on elucidating their physiological function and potential implications in uterine disorders. [ABSTRACT FROM AUTHOR]

A novel visible-light-mediated fluoroalkylation/cyclization tandem process for constructing fluoroalkyl-containing 3,4-disubstituted dihydro-1,5-naphthyridin-2(1H)-ones and 7,8-disubstituted dihydropyrido[3,2-d]pyrimidin-6(5H)-ones has been explored. This method is compatible with a wide range of N-arylcinnamamides as well as sodium fluoroalkylsulfonates (RfSO2Na, Rf = CHF2, CF3, C4F9, C6F13) and avoids the need for any external oxidant or photocatalyst. Mechanism studies revealed that the singlet oxygen coexists with the superoxide radical anion through energy transfer and single electron transfer processes during the photoredox reaction. [ABSTRACT FROM AUTHOR]

The dynamic response of soil to vibrations induced by moving trains has been widely studied using in situ measurements. However, few in situ tests have been conducted to measure the resulting vibration of foundation soils, especially for the foundation of high-speed rail (HSR) in a soft area. In this study, a number of field experiments were conducted on Shanghai-Hangzhou HSR in a suburb of Shanghai, China. The testing instruments were installed in foundation soils just beneath the HSR track to measure the vibration induced by trains moving at different speeds. Test results show the frequencies of foundation soil vibration are characterized by the train speed and geometrical features of the trains and slab track. In the frequency domain, the dominant frequency bands for vertical acceleration, velocity, and displacement of foundation soil decrease successively. In the time domain, the magnitudes of vibration levels at different locations in a soil foundation decrease gradually with increasing distance from the track. Furthermore, higher train speed can result in higher vibration level. Based on the field conditions, a three-dimensional dynamic finite-infinite element model is developed in the time domain. It shows the model is capable of capturing the primary characteristics of train-induced vibration in the field. Key words: dynamic response, soft soils, high-speed train, in situ measurement, finite element method (FEM). La reponse dynamique du sol aux vibrations induites par les trains en mouvement a ete largement etudiee par des mesures in situ. Cependant, peu d'essais in situ ont ete menes pour mesurer les vibrations consequentes des sols de fondation, en particulier pour la fondation de ligne a grande vitesse (LGV) dans une zone molle. Dans cet etude, plusieurs experiences sur le terrain ont ete menees sur le train a grande vitesse Shanghai-Hangzhou dans une banlieue de Shanghai, en Chine. Les instruments de test ont ete installes dans les sols de fondation, juste sous la voie de la LGV, afin de mesurer les vibrations induites par les trains circulant a differentes vitesses. Les resultats des tests montrent que les frequences de vibration des sols de fondation sont caracterisees par la vitesse des trains et les caracteristiques geometriques des trains et des voies sur dalles. Dans le domaine des frequences, les bandes de frequences dominantes pour l'acceleration verticale, la vitesse etle deplacement du sol de fondation diminuent successivement. Dans le domaine temporel, l'ampleur des niveaux de vibration a differents endroits de la fondation du sol diminue progressivement avec l'eloignement de la voie. Et la vitesse plus elevee du train peut entrainer un niveau de vibration plus eleve. Sur la base des conditions naturelles, un modele tridimensionnel dynamique d'elements finisinfinis est developpe dans le domaine temporel. Cela montre que le modele est capable de refleter les principales caracteristiques de la vibration induite par le train sur le terrain. [Traduit par la Redaction] Mots-cles : reponse dynamique, sols mous, train a grande vitesse, mesure in situ, methode des elements finis (MEF)., 1. Introduction The first high-speed rail (HSR) in the world, Tokaido Shinkansen of Japan, was built in 1964. Since then, HSRs have expanded to the entire world due to their [...]

The COVID-19 pandemic has had a significant and enduring influence on global health, including maternal and fetal well-being. Evidence suggests that placental dysfunction is a potential consequence of SARS-CoV-2 infection during pregnancy, which may result in adverse outcomes such as preeclampsia and preterm birth. However, the molecular mechanisms underlying this association remain unclear, and it is uncertain whether a mature placenta can protect the fetus from SARS-CoV-2 infection. To address the above gap, we conducted a transcriptome-based study of the placenta in both maternal and fetal compartments. We collected placental samples from 16 women immediately after term delivery, seven of which had SARS-CoV-2 infection confirmed by PCR before parturition. Notably, we did not detect any viral load in either the maternal or fetal compartments of the placenta, regardless of symptomatic status. We separately extracted total RNA from placental tissues from maternal and fetal compartments, constructed cDNA libraries, and sequenced them to assess mRNA. Our analysis revealed 635 differentially expressed genes when a false discovery rate (FDR ≤ 0.05) was applied in the maternal placental tissue, with 518 upregulated and 117 downregulated genes in the SARS-CoV-2-positive women (n = 6) compared with the healthy SARS-CoV-2-negative women (n = 8). In contrast, the fetal compartment did not exhibit any significant changes in gene expression with SARS-CoV-2 infection. We observed a significant downregulation of nine genes belonging to the pregnancy-specific glycoprotein related to the immunoglobulin superfamily in the maternal compartment with active SARS-CoV-2 infection (fold change range from −13.70 to −5.28; FDR ≤ 0.01). Additionally, comparing symptomatic women with healthy women, we identified 1788 DEGs. Furthermore, a signaling pathway enrichment analysis revealed that pathways related to oxidative phosphorylation, insulin secretion, cortisol synthesis, estrogen signaling, oxytocin signaling, antigen processing, and presentation were altered significantly in symptomatic women. Overall, our study sheds light on the molecular mechanisms underlying the reported clinical risks of preeclampsia and preterm delivery in women with SARS-CoV-2 infection. Nonetheless, studies with larger sample sizes are warranted to further deepen our understanding of the molecular mechanisms of the placenta's anti-viral effects in maternal SARS-CoV-2 infection. [ABSTRACT FROM AUTHOR]

Background/Aim: The impact of myocardial stressors such as high-fat diet (HFD) and pressure overload has been extensively studied. Toll-like receptor 4 (TLR4) deficiency has been suggested to have a protective role in response to these stressors, although some conflicting data exist. Furthermore, there is limited information about the role of TLR4 on cardiac remodeling in response to long-term exposure to stressors. This study aims to investigate the effects of TLR4 deficiency on cardiac histology and physiology in response to chronic stressors. Methods: TLR4-deficient (TLR4−/−) and wild-type (WT) mice were subjected to either HFD or a normal diet (ND) for 28 weeks. Another group underwent abdominal aortic constriction (AAC) or a sham procedure and was monitored for 12 weeks. Inflammatory markers, histology, and echocardiography were used to assess the effects of these interventions. Results: TLR4−/− mice exhibited reduced cardiac hypertrophy and fibrosis after long-term HFD exposure compared to ND without affecting cardiac function. On the other hand, TLR4 deficiency worsened cardiac function in response to AAC, leading to decreased ejection fraction (EF%) and increased end-systolic volume (ESV). Conclusions: TLR4 deficiency provided protection against HFD-induced myocardial inflammation but impaired hemodynamic cardiac function under pressure overload conditions. These findings highlight the crucial role of TLR4 and its downstream signaling pathway in maintaining cardiac output during physiologic cardiac hypertrophy in response to pressure overload. [ABSTRACT FROM AUTHOR]