Molecular network strategy in multi-omics and mass spectrometry imaging

Human physiological activities and pathological changes arise from the coordinated interactions of multiple molecules. Mass spectrometry (MS)-based multi-omics and MS imaging (MSI)-based spatial omics are powerful methods used to investigate molecular information related to the phenotype of interest from homogenated or sliced samples, including the qualitative, relative quantitative and spatial distributions. Molecular network strategy provides efficient methods to help us understand and mine the biological patterns behind the phenotypic data. It illustrates and combines various relationships between molecules, and further performs the molecule identification and biological interpretation. Here, we describe the recent advances of network-based analysis and its applications for different biological processes, such as, obesity, central nervous system diseases, and environmental toxicology.     

干细胞与再生医学技术发展态势研究

20世纪以来,干细胞与再生医学技术一直是国际生物医学领域的热点前沿之一,它为保障人类生命健康、改善人类生存质量和延长人类寿命发挥不可替代的巨大作用。因此,美国、欧洲国家、日本和中国等科技大国均将该领域纳入了国家科研与产业发展的重点战略中,并通过专项扶持、政策补贴、立法保障等方式激励该领域的创新发展。通过对近年来国际科技战略和科技研发态势的梳理分析,发现该领域的国际战略布局规律,揭示我国在该领域的领先优势与弱点,为我国未来干细胞与再生医学技术发展提出相关参考建议。     

1990年和2019年中国心血管疾病负担及危险因素研究

摘要 目的：分析1990年和2019年中国心血管发病、死亡和疾病负担情况。方法：利用2019年全球疾病负担数据库,分析总人群、不同年龄组间1990年和2019年我国心血管发病、死亡、伤残调整寿命年（DALY）、过早死亡损失寿命年(YLL)和伤残损失寿命年(YLD)。并对心血管进行危险因素归因分析。结果：2019年中国心血管发病人数为1234.1万 ,发病率为867.65/10万,较1990年分别增长了132.82%和93.75% 。2019年死亡人数458.43万 ,死亡率为322.30/10万,较1990年分别上升了89.12%和57.39%。2019年中国心血管DALY、YLD和YLL分别为9193.31万人年、1038.39万人年和8154.93万人年。较1990年分别上升了50.07%、146.82%和45.48%。2019年发病率、死亡率和DALY率最高的年龄组均为＞70年龄组,分别为4646.78/10万、3057.82/10万和52696.68/10万。中国心血管归因于代谢危险导致的死亡人数、DALY和YLL最多,分别为3272924人、67112754人年和59934426人年。结论：我国心血管的疾病负担在1990-2019年间有较大增长,应采取积极的预防措施以减轻心血管的疾病负担。     

Process-induced cell cycle oscillations in CHO cultures: Online monitoring and model-based investigation

The influence of process strategies on the dynamics of cell population heterogeneities in mammalian cell culture is still not well understood. We recently found that the progression of cells through the cell cycle causes metabolic regulations with variable productivities in antibody-producing Chimese hamster ovary (CHO) cells. On the other hand, it is so far unknown how bulk cultivation conditions, for example, variable nutrient concentrations depending on process strategies, can influence cell cycle-derived population dynamics. In this study, process-induced cell cycle synchronization was assessed in repeated-batch and fed-batch cultures. An automated flow cytometry set-up was developed to measure the cell cycle distribution online, using antibody-producing CHO DP-12 cells transduced with the cell cycle-specific fluorescent ubiquitination-based cell cycle indicator (FUCCI) system. On the basis of the population-resolved model, feeding-induced partial self-synchronization was predicted and the results were evaluated experimentally. In the repeated-batch culture, stable cell cycle oscillations were confirmed with an oscillating G1 phase distribution between 41% and 72%. Furthermore, oscillations of the cell cycle distribution were simulated and determined in a (bolus) fed-batch process with up to cells/ml. The cell cycle synchronization arose with pulse feeding only and ceased with continuous feeding. Both simulated and observed oscillations occurred at higher frequencies than those observable based on regular (e.g., daily) sample analysis, thus demonstrating the need for high-frequency online cell cycle analysis. In summary, we showed how experimental methods combined with simulations enable the improved assessment of the effects of process strategies on the dynamics of cell cycle-dependent population heterogeneities. This provides a novel approach to understand cell cycle regulations, control cell population dynamics, avoid inadvertently induced oscillations of cell cycle distributions and thus to improve process stability and efficiency.     

Flight initiation distance and escape behavior in the black redstart (Phoenicurus ochruros)

There are many anti‐predatory escape strategies in animals. A well‐established method to assess escape behavior is the flight initiation distance (FID), which is the distance between prey and predator at which an animal flees. Previous studies in various species throughout the animal kingdom have shown that group size, urbanization, and distance to refuge and body mass affect FID. In most species, FID increases if body mass, group size or distance to refuge decreases. However, how age and sexual dimorphism affect FID is rather unknown. Here, we assess the escape behavior and FID of the black redstart (Phoenicurus ochruros), a small turdid passerine. When approached by a human, males initiated flights later, that is allowing a closer approach than females. Males of this species are more conspicuous, and therefore, may exhibit aposematism to deter potential predators or are less fearful than females. Additionally, juveniles fled at shorter distances and fled to lower heights than adults. Lastly, concerning escape strategy, black redstarts, unless other passerine birds, fled less often into cover, but rather onto open or elevated spots. Black redstarts are especially prone to predation by ambushing predators that might hide in cover. Hence, this species most likely has a higher chance of escaping by fleeing to an open spot rather than to a potentially risky cover.     

Effects of starvation on death‐feigning in adult Eucryptorrhynchus brandti (Coleoptera: Curculionidae)

In insects, death‐feigning is an effective defence strategy. Eucryptorrhynchus brandti, a major borer pest in China, has a weak flight ability and exhibits obvious death‐feigning behaviour when disturbed. Despite a large number of studies of its biological and ecological properties as well as control methods, the death‐feigning behaviour has not been specifically described. In laboratory conditions, we recorded the survival rate under starvation and feeding conditions and evaluated the effect of starvation on the duration and occurrence of death‐feigning. In a continuous experiment, we examined variation in the death‐feigning duration every day over 7 day. Then, we evaluated the effects of starvation for 3, 6 and 9 day in a non‐continuous experiment and further observed variation in the death‐feigning intensity. We found that starvation significantly affected the survival rate. Survival time was significantly longer in the starvation group than in the feeding group, and females had longer survival times than males (female: 14 day, male: 8 day). In the continuous experiment, starved E. brandti had the longest duration of death‐feigning at 2 day, followed by a significant decrease. In the non‐continuous experiment, the duration and proportion of death‐feigning decreased significantly as the duration of starvation increased and were significantly lower than feeding. These observations suggest that starvation is a non‐negligible factor in the death‐feigning behaviour of E. brandti adults, facilitating the interpretation of future ecological and behavioural data of thanatosis.     

广东西樵山细石叶石核的开发策略

长期以来,细石叶技术的发展和传播是更新世末期到全新世初期文化传播、人群迁徙和生态适应研究领域探讨的重要课题。20世纪50年代,发现于广东西樵山石器制造场的大批细石叶技术产品,突破了传统意义上对细石叶技术流行、传播范围的认识。早期研究中不少学者就西樵山细石叶制品的形态特征、分布情况进行了介绍,随后鲜见后续研究,缺乏对技术内涵、石核开发策略的深入解析,亦未开展对其所指示的文化传播与人口迁徙问题的探讨。本文选取收藏于中山大学人类学博物馆的343件细石叶石核,通过对石料、毛坯类型、台面类型和数量、剥片面等多方位观察以及对相关技术数值的测量统计,建构西樵山细石叶石核开发策略的模式。这项工作总结了西樵山细石叶技术的特点,并与其他区域的细石叶技术进行对比,加深了对出现在亚热带地区的细石叶技术的认识,为尝试进一步讨论其可能的技术源流和指示人口迁徙与文化传播提供了基础。     

Evolutionarily stable strategies of migration in heterogeneous environments

By means of a simulation model we are showing that the rates of migration can be related to avoidance of competition between relatives, especially in clonal organisms. This could result in a strong selective pressure for migration, even at a high cost. In addition, if the habitat is fragmented, migration can strongly affect local dynamics and result in a dramatic decrease of the densities in some places. In parthenogenetically reproducing organisms like aphids, the level of relatedness in local populations is expected to be very high and therefore they can serve as a good model group for testing these hypotheses. This revised version was published online in July 2006 with corrections to the Cover Date.     

Molecular cloning and phylogenetic analysis of the small cytoplasmic RNA from Listeria monocytogenes

A molecular cloning strategy has been designed to isolate the gene that encodes the small cytoplasmic RNA (scRNA) component of bacterial signal recognition particles. Using this strategy a putative Listeria monocytogenes scRNA lambda gt11 recombinant clone was isolated. A previously described complementation assay developed to genetically select functional homologues of 4.5S RNA and scRNA of bacteria confirmed that the lambda gt11 recombinant clone isolated encoded for the scRNA from L. monocytogenes. A secondary structure for this scRNA is proposed and a phylogenetic comparison of the 276 base L. monocytogenes scRNA with previously characterised Gram-positive bacterial scRNAs is also presented.