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Chromatin bridges mostly arise from dicentric chromosomes resulting from chromosome end-to-end fusions due to telomere crisis, erroneous DNA repair, and neocentromere formation. Accumulation of interchromosomal linkages also leads to chromatin bridges. Actomyosin contractile forces can break chromatin bridges after they have been stretched to extend. TREX1 is a 3′–5′ exonuclease that has been implicated in processing stretched chromatin bridges after nuclear envelope rupture. TREX1 degrades bridge DNA to generate extensive single-stranded DNA (ssDNA) along the bridges. ANKLE1 is a midbody-tethered endonuclease that cleaves DNA bridges to avoid catastrophic breakage of bridges by actomyosin-mediated mechanical forces. The breakage of chromatin bridges induces micronuclei, the DNA of which is prone to damage. Damaged micronuclei promote chromothripsis. Genetic material is organized in the form of chromosomes, which need to be segregated accurately into two daughter cells in each cell cycle. However, chromosome fusion or the presence of unresolved interchromosomal linkages lead to the formation of chromatin bridges, which can induce DNA lesions and genome instability. Persistent chromatin bridges are trapped in the cleavage furrow and are broken at or after abscission, the final step of cytokinesis. In this review, we focus on recent progress in understanding the mechanism of bridge breakage and resolution. We discuss the molecular machinery and enzymes that have been implicated in the breakage and processing of bridge DNA. In addition, we outline both the immediate outcomes and genomic consequences induced by bridge breakage. [ABSTRACT FROM AUTHOR]

Starting from document research, this paper analyzes the mechanism of the risk spillover effect from developed capital markets to the Chinese capital market. After that, this paper conducts an empirical study on the risk spillover effect of developed capital markets on the Chinese capital market by using the DCC-GARCH model. Then the impact degree of global major stock market fluctuations on the Chinese stock market is measured. The analysis shows that there exists a significant risk spillover effect of developed capital markets on the Chinese capital market, but the effect began to weaken after the financial crisis and the size of the spillover effect can be affected by macro factors such as geographical locations, foreign trade, and foreign investment. [ABSTRACT FROM AUTHOR]

The enhancement of heat transfer caused by longitudinal vortex phenomena has been a widely studied topic for a significant period in fluid mechanics and heat transfer. However, despite extensive efforts, the current understanding of longitudinal vortex flow and the involved physical mechanisms leading to enhanced heat transfer remains qualitative in nature. To unveil the physical mechanisms underlying the enhancement of convective heat transfer by longitudinal vortices, further quantitative research and in-depth discussions are necessary. By performing detailed derivations and proofs of the equations, this study aims to further understand the relationship between local vortex variations and heat transfer performance. The results indicate that the presence of longitudinal vortices alters the gradient of the convective term and ultimately leads to enhanced heat transfer performance. Based on the derived results, corresponding metrics have been proposed to quantitatively analyze the degree of heat transfer enhancement due to longitudinal vortices. This proposed quantitative analysis metric has been applied to evaluate the heat transfer performance of a cross-wavy primary surface heat exchanger, validating the reliability of the metrics. The research content and conclusions provide valuable insights for both theoretical investigations and practical engineering applications in the field of enhanced heat transfer. [ABSTRACT FROM AUTHOR]

Problem: Preeclampsia (PE) is a serious pregnancy complication characterized by inflammation and impaired trophoblast motility. Puerarin (Pue) is a functional compound with anti‐PE potential. The current study aimed to explore the therapeutic effects of Pue on PE as well as the associated mechanism by focusing on the interaction between Pue and microRNAs (miRs). Methods of study: Human villous trophoblast HTR‐8/SVneo cells were treated with TNF‐α and Pue, and a change in miR expression profile was determined. The anti‐PE effects of Pue were validated in rat models by measuring blood pressure, 24‐h proteinuria, and cytokine levels. The mechanism was explored by focusing on miR‐181b‐5p/RBAK axis. Results: The induction of PE increased blood pressure and 24‐h proteinuria, and induced TNF‐α, IL‐1β, and IL‐6 levels, which was reversed by Pue. In in vitro assays, TNF‐α suppressed viability, induced apoptosis and inflammatory response, and inhibited migration in trophoblasts, which was attenuated by Pue. At molecular level, the expression level of miR‐181b‐5p was both induced in vivo and in vitro with the development of PE symptoms, contributing to the inhibited expression of RBAK. The induced expression of miR‐181b‐5p under Pue treatment showed that the reinduction of miR‐181b‐5p counteracted the effects of Pue, indicating the key role of the miR in the protective effects of Pue against PE. Conclusions: The current study verified the anti‐PE function of Pue: the compound suppressed inflammatory response associated with PE, and improved trophoblast motility. The effects depended on the inhibition of miR‐181b‐5p that inhibited the expression of RBAK. [ABSTRACT FROM AUTHOR]

Objective: We studied the reduction of soluble and highly toxic selenite to elemental red selenium, under aerobic condition by Pseudomonas alcaliphila MBR, with organic carbon as electron donor., Results: The strain could grow under pH 6-11 and resist to high concentration of selenite with the minimal inhibitory concentration of 50 mmol/L. After 5 days, the strain used sodium citrate as electron donor, and reduced 2.0 mmol/L selenite to elemental red selenium from the culture fluid, the elemental red selenium was stored outside the cells. The glutathione and nitrate could increase the number of reduction rate., Conclusion: This study implies the application of Pseudomonas alcaliphila MBR to convert selenite to elemental red selenium.