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摘要： Aerobic respiration is essential to almost all eukaryotes and sensing oxygen is a key determinant of survival. Analogous but mechanistically different oxygen-sensing pathways were adopted in plants and metazoan animals, and include ubiquitin-mediated degradation of transcription factors and direct sensing via non-heme iron(Fe2+)-dependent-dioxygenases. Key roles for oxygen sensing have been identified in both groups, with downstream signalling focussed on regulating gene transcription and chromatin modification to control development and stress responses. Components of sensing systems are promising targets for human therapeutic intervention and developing stress-resilient crops. Here, we review current knowledge about the origins, commonalities and differences between oxygen sensing in plants and animals.

关键词： Epigenetics   Genomic sequence   Hyperspectral autofluorescence   Organizer   Embryology   Metabolism   Cell death   Cytochrome P450   Steroid biology  

摘要： Background Progesterone receptor membrane component 1 (PGRMC1) is often elevated in cancers, and exists in alternative states of phosphorylation. A motif centered on PGRMC1 Y180 was evolutionarily acquired concurrently with the embryological gastrulation organizer that orchestrates vertebrate tissue differentiation. Results Here, we show that mutagenic manipulation of PGRMC1 phosphorylation alters cell metabolism, genomic stability, and CpG methylation. Each of several mutants elicited distinct patterns of genomic CpG methylation. Mutation of S57A/Y180/S181A led to increased net hypermethylation, reminiscent of embryonic stem cells. Pathways enrichment analysis suggested modulation of processes related to animal cell differentiation status and tissue identity, as well as cell cycle control and ATM/ATR DNA damage repair regulation. We detected different genomic mutation rates in culture. Conclusions A companion manuscript shows that these cell states dramatically affect protein abundances, cell and mitochondrial morphology, and glycolytic metabolism. We propose that PGRMC1 phosphorylation status modulates cellular plasticity mechanisms relevant to early embryological tissue differentiation.

关键词： 乳酸菌   分离鉴定   系统进化树   酸耐受性   胆盐耐受性   生长特性  

摘要： 为了筛选性状良好的动物源乳酸菌为微生态制剂的制备提供候选菌株,试验对鸡、雏鸭、甲鱼和小鼠的肠道内容物进行细菌分离鉴定,并对鉴定的乳酸菌进行耐酸、耐胆盐和生长特性研究。结果表明:从鸡、雏鸭、甲鱼和小鼠肠道内容物中各分离出了一株乳酸菌;相比其他三株乳酸菌,分离自甲鱼肠道的类肠膜魏斯氏菌生长性能优良,具备较强的耐酸、耐胆盐能力,且在pH值为7和pH值为4.5的条件下均具有较快的生长速度。说明分离自甲鱼的乳酸菌能够作为微生态制剂制备的候选菌株。

关键词： FMEA   image-guided small animal irradiators   radiation biology  

摘要： Purpose Image-guided small animal irradiators (IGSAI) are increasingly being adopted in radiation biology research. These animal irradiators, designed to deliver radiation with submillimeter accuracy, exhibit complexity similar to that of clinical radiation delivery systems, including image guidance, robotic stage motion, and treatment planning systems. However, physics expertise and resources are scarcer in radiation biology, which makes implementation of conventional prescriptive QA infeasible. In this study, we apply the failure modes and effect analysis (FMEA) popularized by the AAPM task group 100 (TG-100) report to IGSAI and radiation biological research. Methods Radiation biological research requires a change in paradigm where small errors to large populations of animals are more severe than grievous errors that only affect individuals. To this end, we created a new adverse effects severity table adapted to radiation biology research based on the original AAPM TG-100 severity table. We also produced a process tree which outlines the main components of radiation biology studies performed on an IGSAI, adapted from the original clinical IMRT process tree from TG-100. Using this process tree, we created and distributed a preliminary survey to eight expert IGSAI operators in four institutions. Operators rated proposed failure modes for occurrence, severity, and lack of detectability, and were invited to share their own experienced failure modes. Risk probability numbers (RPN) were calculated and used to identify the failure modes which most urgently require intervention. Results Surveyed operators indicated a number of high (RPN >125) failure modes specific to small animal irradiators. Errors due to equipment breakdown, such as loss of anesthesia or thermal control, received relatively low RPN (12-48) while errors related to the delivery of radiation dose received relatively high RPN (72-360). Errors identified could either be improved by manufacturer intervention

关键词： cis-regulatory   eye development   gene regulatory networks   retina differentiation   single-cell   transcriptome  

摘要： The ontogeny of the vertebrate retina has been a topic of interest to developmental biologists and human geneticists for many decades. Understanding the unfolding of the genetic program that transforms a field of progenitors cells into a functionally complex and multi-layered sensory organ is a formidable challenge. Although classical genetic studies succeeded in identifying the key regulators of retina specification, understanding the architecture of their gene network and predicting their behavior are still a distant hope. The emergence of next-generation sequencing platforms revolutionized the field unlocking the access to genome-wide datasets. Emerging techniques such as RNA-seq, ChIP-seq, ATAC-seq, or single cell RNA-seq are used to characterize eye developmental programs. These studies provide valuable information on the transcriptional and cis-regulatory profiles of precursors and differentiated cells, outlining the trajectories that connect each intermediate state. Here, recent systems biology efforts are reviewed to understand the genetic programs shaping the vertebrate retina.

关键词： Calcium isotopes   Vertebrate biology   Palaeobiology   Bioarchaeology   Biomedical research   Bone loss  

摘要： Beyond their established uses in Earth and Planetary sciences, calcium (Ca) isotopes have a promising future in the study of the biology of present and past vertebrates, including humans. Early work paved the way to the ongoing research on the potential of Ca isotopes as relevant tools to disciplines other than geology, including palaeobiology, bioarchaeology and biomedical research. In this article, we first review the rationale behind the cycling of Ca isotopes in vertebrate organisms. We then summarize and discuss the use of Ca isotopes as dietary tracers from trophic reconstructions in past vertebrate ecosystems to the tracking of early life dietary transitions. Next, we review and examine the research outcomes on the potential of Ca isotopes as biomarkers of bone loss in physiological and pathological conditions such as bone cancers and osteoporosis. While emphasizing the needs of future research in each of these applications, we suggest new potential uses of Ca isotopes in vertebrate biology. Finally, we identify challenges and barriers faced when developing such interdisciplinary projects and suggest how these can be overcome.

关键词： 吡咯喹啉醌   生物学功能   安全性   饲料添加剂  

摘要： 吡咯喹啉醌(PQQ)是一种具有高度水溶性和稳定性的芳香族三环邻醌化合物,在微生物、植物、动物中广泛存在。PQQ作为一种类维生素辅酶,具有促进线粒体发生、改善能量代谢、抗氧化、促进生长和繁殖、免疫调控和抗炎、抗应激、神经保护等生物学功能。PQQ在营养和健康方面具有积极作用,目前美国和欧盟已批准其作为膳食补充剂。本文综述了PQQ的生物学功能、安全性评价及其在动物营养方面的研究进展,以期为PQQ作为新饲料添加剂的开发及在动物生产上的应用提供参考。

关键词： 微量元素   生物学功能   反刍动物   补充方法  

摘要： 微量元素是动物体内必需的营养物质,在生命活动中有着重要的生物学功能,摄入过量、不足或不平衡都会降低动物的生长、生产、发育和繁育性能。微量元素添加剂预混料是反刍动物补饲精料的重要组成成分,本文着重介绍了反刍动物补充微量元素的主要方法。

关键词： 酵母壁多糖   生物学功能   反刍动物   肠道免疫   生产性能  

摘要： 冬春换季和断奶应激常会导致反刍动物胃肠道功能紊乱、机体免疫力低下、腹泻脱水甚至死亡的情况。酵母壁多糖作为一种绿色、安全、有效的功能性多糖,不仅能提高动物生产性能、调节肠道菌群平衡、提高免疫力以及降低机体应激反应,还能减少饲料中的抗生素用量,减少药品在畜禽产品中的残留。另外酵母壁多糖化学性质稳定,无药物残留及无耐药性,对发展无抗养殖具有重要意义。文章主要介绍了酵母壁多糖的结构、生物学功能及其对反刍动物的影响,为酵母壁多糖产品的开发和应用提供参考。

关键词： Newspeak   Michurinism   Lysenkoism   New biology   Zoology   Polish biology  

摘要： The "New Biology" that arose in the Eastern Block during Stalinist times was based on the idea of the heritability of acquired characteristics. In rejecting the paradigm of Mendelian chromosome genetics as well as science-based farming, the New Biology led to a deterioration of scientific life and the free exchange of ideas. In imposing Lysenko's ideas onto zoology, the New Biology adopted the totalitarian language of Newspeak, which dominated public discourse in communist countries. Newspeak had several defining elements: a limited dictionary, strong valuations, binary oppositions, the magical function of language, militarization, and ritualization of language. In this study, the concept of Newspeak is used to analyze primary sources (publications, speeches, and conference discussions) in Polish zoology in the period between 1948 and 1956. Once the practice of Newspeak began to wane, so did the New Biology that had been founded on this specific ritualistic language.