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排序方式: 共有1160条查询结果,搜索用时 46 毫秒
231.
Daniel H. Mendelsohn Katja Schnabel Andreas Mamilos Samuel Sossalla Steffen Pabel Georg Daniel Duerr Karsten Keller Volker H. Schmitt Friedrich Barsch Nike Walter Ronald Man Yeung Wong Thaqif El Khassawna Tanja Niedermair Volker Alt Markus Rupp Christoph Brochhausen 《International journal of molecular sciences》2022,23(9)
Mitochondria play a crucial role in cell physiology and pathophysiology. In this context, mitochondrial dynamics and, subsequently, mitochondrial ultrastructure have increasingly become hot topics in modern research, with a focus on mitochondrial fission and fusion. Thus, the dynamics of mitochondria in several diseases have been intensively investigated, especially with a view to developing new promising treatment options. However, the majority of recent studies are performed in highly energy-dependent tissues, such as cardiac, hepatic, and neuronal tissues. In contrast, publications on mitochondrial dynamics from the orthopedic or trauma fields are quite rare, even if there are common cellular mechanisms in cardiovascular and bone tissue, especially regarding bone infection. The present report summarizes the spectrum of mitochondrial alterations in the cardiovascular system and compares it to the state of knowledge in the musculoskeletal system. The present paper summarizes recent knowledge regarding mitochondrial dynamics and gives a short, but not exhaustive, overview of its regulation via fission and fusion. Furthermore, the article highlights hypoxia and its accompanying increased mitochondrial fission as a possible link between cardiac ischemia and inflammatory diseases of the bone, such as osteomyelitis. This opens new innovative perspectives not only for the understanding of cellular pathomechanisms in osteomyelitis but also for potential new treatment options. 相似文献
232.
233.
Genetic Dissection of Light-Regulated Adventitious Root Induction in Arabidopsis thaliana Hypocotyls
Yinwei Zeng Sebastien Schotte Hoang Khai Trinh Inge Verstraeten Jing Li Ellen Van de Velde Steffen Vanneste Danny Geelen 《International journal of molecular sciences》2022,23(10)
Photomorphogenic responses of etiolated seedlings include the inhibition of hypocotyl elongation and opening of the apical hook. In addition, dark-grown seedlings respond to light by the formation of adventitious roots (AR) on the hypocotyl. How light signaling controls adventitious rooting is less well understood. Hereto, we analyzed adventitious rooting under different light conditions in wild type and photomorphogenesis mutants in Arabidopsis thaliana. Etiolation was not essential for AR formation but raised the competence to form AR under white and blue light. The blue light receptors CRY1 and PHOT1/PHOT2 are key elements contributing to the induction of AR formation in response to light. Furthermore, etiolation-controlled competence for AR formation depended on the COP9 signalosome, E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC (COP1), the COP1 interacting SUPPRESSOR OF PHYA-105 (SPA) kinase family members (SPA1,2 and 3) and Phytochrome-Interacting Factors (PIF). In contrast, ELONGATED HYPOCOTYL5 (HY5), suppressed AR formation. These findings provide a genetic framework that explains the high and low AR competence of Arabidopsis thaliana hypocotyls that were treated with dark, and light, respectively. We propose that light-induced auxin signal dissipation generates a transient auxin maximum that explains AR induction by a dark to light switch. 相似文献
234.
Philipp Kasper Jaco Selle Christina Vohlen Rebecca Wilke Celien Kuiper-Makris Oleksiy Klymenko Inga Bae-Gartz Charlotte Schmig Alexander Quaas Bjrn Schumacher Münevver Demir Martin Bürger Sonja Lang Anna Martin Hans-Michael Steffen Tobias Goeser Jrg Dtsch Miguel A. Alejandre Alcazar 《International journal of molecular sciences》2022,23(10)
Maternal obesity predisposes for hepato-metabolic disorders early in life. However, the underlying mechanisms causing early onset dysfunction of the liver and metabolism remain elusive. Since obesity is associated with subacute chronic inflammation and accelerated aging, we test the hypothesis whether maternal obesity induces aging processes in the developing liver and determines thereby hepatic growth. To this end, maternal obesity was induced with high-fat diet (HFD) in C57BL/6N mice and male offspring were studied at the end of the lactation [postnatal day 21 (P21)]. Maternal obesity induced an obese body composition with metabolic inflammation and a marked hepatic growth restriction in the male offspring at P21. Proteomic and molecular analyses revealed three interrelated mechanisms that might account for the impaired hepatic growth pattern, indicating prematurely induced aging processes: (1) Increased DNA damage response (γH2AX), (2) significant upregulation of hepatocellular senescence markers (Cdnk1a, Cdkn2a); and (3) inhibition of hepatic insulin/insulin-like growth factor (IGF)-1-AKT-p38-FoxO1 signaling with an insufficient proliferative growth response. In conclusion, our murine data demonstrate that perinatal obesity induces an obese body composition in male offspring with hepatic growth restriction through a possible premature hepatic aging that is indicated by a pathologic sequence of inflammation, DNA damage, senescence, and signs of a possibly insufficient regenerative capacity. 相似文献
235.
236.
In language learning, strong relationships between Gold-style models and query models have recently been observed: in some quite general setting Gold-style learners can be replaced by query learners and vice versa, without loss of learning capabilities. These ‘equalities’ hold in the context of learning indexable classes of recursive languages. 相似文献
237.
河流景观是人类需求与自然基底相互作用形成的复
杂、多尺度嵌套的社会生态和水文地貌系统。基于水文地貌学
原理的“河流样式框架”为理解河流“形式与过程”之间的关
系提供了一个成熟的分析工具。系统梳理河流样式框架的基本
原则、具体步骤与核心内容,提出多尺度的空间层级划分、河
流样式与地貌单元的分类体系是该框架解释河流特征与河流行
为的核心方法。进而在流域尺度依据地貌状况与修复潜力评估
结果确定各个河段修复管理的优先次序,在河段尺度通过河流
演变轨迹分析预测河流的变化趋势。以期为“基于过程”的河
流景观修复设计与行动计划提供理论支持。 相似文献
238.
Prerna Arora Lu Zhang Cheila Rocha Luise Graichen Inga Nehlmeier Amy Kempf Anne Cossmann Gema Morillas Ramos Eva Baier Bjrn Tampe Onnen Moerer Steffen Dickel Martin S. Winkler Georg M. N. Behrens Stefan Phlmann Markus Hoffmann 《International journal of molecular sciences》2022,23(22)
Recently, a recombinant SARS-CoV-2 lineage, XD, emerged that harbors a spike gene that is largely derived from the Omicron variant BA.1 in the genetic background of the Delta variant. This finding raised concerns that the recombinant virus might exhibit altered biological properties as compared to the parental viruses and might pose an elevated threat to human health. Here, using pseudotyped particles, we show that ACE2 binding and cell tropism of XD mimics that of BA.1. Further, XD and BA.1 displayed comparable sensitivity to neutralization by antibodies induced upon vaccination with BNT162b2/Comirnaty (BNT) or BNT vaccination followed by breakthrough infection. Our findings reveal important biological commonalities between XD and Omicron BA.1 host cell entry and its inhibition by antibodies. 相似文献
239.
Joseila Maldaner Gerusa Pauli Kist Steffen Evandro Luiz Missio Cleber Witt Saldanha Rosana Matos De Morais Ricardo Bemfica Steffen 《The International journal of environmental studies》2020,77(2):255-263
ABSTRACTLovegrass (Eragrostis plana) is the most important invasive plant in pastures of southern Brazil. The research evaluated the potential of Ruta graveolens (rue) and Schinus terebinthifolius (Brazilian peppertree) essential oils (EOs) to inhibit germination and initial development of lovegrass. The in vitro treatments tested were control (distilled water), alcohol control, 0.001, 0.005, 0.01, 0.05 and 0.1% (v/v) of both EOs. Higher concentrations of these EOs were applied to germinated plants under greenhouse conditions. The EOs of both species were effective in reducing lovegrass germination, with emphasis on rue. Height and shoot dry mass, at greenhouse conditions, were significantly reduced by both EOs, especially when applied at a concentration of 1%. The results point to the potential of rue and Brazilian peppertree EOs for the formulation of natural herbicides. 相似文献
240.
For slender fixed beds, the void fraction and flow properties are complex topics. Different factors can influence the local bed structure. For statistical analysis, 2800 fixed beds have been generated and the impact of friction factor and reactor-to-particle diameter ratio on the distribution has been shown. With particle-resolved computational fluid dynamics, all local structure effects are taken into account for the flow simulations. Pressure drop measurements and simulations showed that these effects can lead to areas with low flow resistance, leading to overestimated pressure drop by typical correlations up to 85 %. 相似文献