体外与非体外循环冠状动脉旁路移植术再血管化率的系统评价

目的:系统评价采用体外循环与非体外循环下冠状动脉旁路移植术比较,治疗冠状动脉粥样硬化性心脏病的再血管化率。方法:计算机检索MEDLINE(1966～2010.3)、EMbase(1984～2010.3)、Cochrane临床对照试验资料库(2010年第2期)和中国生物医学文献数据库(1979～2010.3),同时手工检索所有纳入试验的参考文献,质量评价后用RevMan 5.0软件进行Meta分析。结果:共纳入2个随机对照试验,包括2276例患者。Meta分析结果显示:体外循环组的再血管化率高于单用非体外循环组,其差异有统计学意义P<0.00001[OR=1.78,95%C(I1.40,2.26)]。结论:当前的证据表明,体外循环下冠状动脉旁路移植术在治疗冠心病时,再血管化率比非体外循环高;评价患者长期预后有一定指导意义。由于纳入研究随访时间较短,上述结论尚需要高质量、大样本、长时间的随机双盲对照试验进一步证实。     

基于二元水循环效率提升的城市湿地修复策略

城市湿地对人地系统的水循环调节起着关键作用。随着城市的发展,水资源短缺问题日益突出,探讨湿地在缓解城市水资源危机中的作用具有重要意义。基于“自然-社会”二元水循环理论,综合分析了我国城市用水量在全国总用水量占比急剧增加的现状,以及城市水循环效率低下的重点问题;基于城市水循环途径的取水、输水、用水、排水和回水五个阶段,系统提出湿地的保护恢复有助于改善城市水资源利用状况,增强城市湿地空间优化配置和水资源可持续利用的协同效应;充分考虑城市生态空间整体优化及湿地布局,全面阐释在城市国土空间规划指导下,通过增加城市水循环中社会水回归容量和缩短社会水回归距离,提升城市水循环效率,充分发挥湿地生态工程对城市水循环优化的调控作用;最后,兼顾城市中长期规划发展的协调性、适应性,探讨了湿地保护修复以提升水循环效率的策略,包括多功能水源地建设、缩短汇水距离、多级净水、营建小微湿地以及构建自循环理念的再生系统等具体措施,为城市湿地资源空间规划的整体布局提供重要依据,对促进城市水资源可持续利用和建设人与自然和谐共生的韧性城市具有重要意义。     

Sensitivity analysis of the tree distribution model Phenofit to climatic input characteristics: implications for climate impact assessment

Species distributions are already affected by climate change. Forecasting their long‐term evolution requires models with thoroughly assessed validation. Our aim here is to demonstrate that the sensitivity of such models to climate input characteristics may complicate their validation and introduce uncertainties in their predictions. In this study, we conducted a sensitivity analysis of a process‐based tree distribution model Phenofit to climate input characteristics. This analysis was conducted for two North American trees which differ greatly in their distribution and eight different types of climate input for the historic period which differ in their spatial (local or gridded data) and temporal (daily vs. monthly) resolution as well as their type (locally recorded, extrapolated or simulated by General Circulation Models). We show that the climate data resolution (spatial and temporal) and their type, highly affect the model predictions. The sensitivity analysis also revealed, the importance, for global climate change impact assessment, of (i) the daily variability of temperatures in modeling the biological processes shaping species distribution, (ii) climate data at high latitudes and elevations and (iii) climate data with high spatial resolution.     

Occurrence of Rotifera in the field user natural and intentionally-changed conditions. II. Lake Numasawa

Seasonal and vertical occurrences of representative rotifer species were recorded together with such taxa as Cyanophycea, Phytomastigophorea, Bacillariophycea, Protozoa, Rotifera and Crustacea, from 1982 to 1986 at two sites S1 (natural) and S2 (nearby water circulated since 1952). 1) The following species were observed from S1: K. hiemalis, C. ovalis, N. labis, L. patella and Anuraeopsis sp., from S2: B. urceolaris and A. ecaudis, 2) P. hudsoni appeared in 1984 as a successor to P. truncatum, 3) K. longispina was negatively associated with P. t. vulgaris, 4) Synchaeta spp suddenly appeared at both sites in 1985, 5) K. cochlearis, B. calyciflorus, Proalides sp., Diurella sp., N. labis, B. urceolaris and bdelloids did not appear until 1986, 6) The following species decreased or disappeared: A. p. herricki and Collotheca sp. since 1982, C. coenobasis, C. hippocrepis and K. hiemalis since 1984, 7) A complicated relation was observed between rotifer population density and other plankton. 8) Occurrence of Rotifera seemed to be affected by circulation of an electric power plant.     

Morphological arrangement of the coronary vasculature in a shark (Squalus sucklei) and a teleost (Oncorhynchus mykiss)

The coronary circulation is of great importance in maintaining cardiovascular function and consequently it has been extensively studied in many mammalian species. However, much less attention has been paid to the coronary circulation in other vertebrates. For example, while elasmobranch fishes are of special interest as they are the most ancient lineage of vertebrates to possess a coronary circulation, only qualitative studies exist on their coronary circulation and most concern the architecture of the large arteries. Our study tested the prediction that the coronary circulation of sharks is better developed than previously thought. However, to test this idea, a methodology was needed to quantify vascularity, vessel morphology and oxygen diffusion distances in a heart with predominantly spongy myocardium. Here, we describe this methodology using dogfish and rainbow trout and suggest that the dogfish spongy myocardium appears to rely predominantly on the coronary circulation for its oxygen supply, an arrangement that contrasts with the spongy myocardial tissue of rainbow trout. In support of this suggestion, the density of the microvasculature of the spongy myocardial tissue of dogfish exceeded that of their compact tissue. Although vascularity in the compact myocardium of dogfish was significantly lower than trout, intervascular distances were similar on account of a significantly larger vessel diameter in dogfish, which corresponds to a larger red blood cell size of the dogfish when compared to trout. J. Morphol. 277:896–905, 2016. © 2016 Wiley Periodicals, Inc.     

Evolution of substrate specificity for the bile salt transporter ASBT (SLC10A2)

The apical Na(+)-dependent bile salt transporter (ASBT/SLC10A2) is essential for maintaining the enterohepatic circulation of bile salts. It is not known when Slc10a2 evolved as a bile salt transporter or how it adapted to substantial changes in bile salt structure during evolution. We characterized ASBT orthologs from two primitive vertebrates, the lamprey that utilizes early 5α-bile alcohols and the skate that utilizes structurally different 5β-bile alcohols, and compared substrate specificity with ASBT from humans who utilize modern 5β-bile acids. Everted gut sacs of skate but not the more primitive lamprey transported (3)H-taurocholic acid (TCA), a modern 5β-bile acid. However, molecular cloning identified ASBT orthologs from both species. Cell-based assays using recombinant ASBT/Asbt's indicate that lamprey Asbt has high affinity for 5α-bile alcohols, low affinity for 5β-bile alcohols, and lacks affinity for TCA, whereas skate Asbt showed high affinity for 5α- and 5β-bile alcohols but low affinity for TCA. In contrast, human ASBT demonstrated high affinity for all three bile salt types. These findings suggest that ASBT evolved from the earliest vertebrates by gaining affinity for modern bile salts while retaining affinity for older bile salts. Also, our results indicate that the bile salt enterohepatic circulation is conserved throughout vertebrate evolution.     

Cellular senescence in normal and adverse pregnancy

Cellular senescence (CS) is defined as a state of terminal proliferation arrest accompanied by morphological alterations, pro-inflammatory phenotype, and metabolic changes. In recent years, the implications of senescence in numerous physiological and pathological conditions such as development, tissue repair, aging, or cancer have been evident. Some inductors of senescence are tissue repair pathways, telomere shortening, DNA damage, degenerative disorders, and wound healing. Lately, it has been demonstrated that CS plays a decisive role in the development and progression of healthy pregnancy and labor. Premature maternal-fetal tissues senescence (placenta, choriamniotic membranes, and endothelium) is implicated in many adverse pregnancy outcomes, including fetal growth restriction, preeclampsia, preterm birth, and intrauterine fetal death. Here we discuss cellular senescence and its association with normal pregnancy development and adverse pregnancy outcomes. Current evidence allows us to establish the relevance of CS in processes associated with the appropriate development of placentation, the progression of pregnancy, and the onset of labor; likewise, it allows us to understand the undeniable participation of CS deregulation in pathological processes associated with pregnancy.     

Experimental quantification of the fluid dynamics in blood-processing devices through 4D-flow imaging: A pilot study on a real oxygenator/heat-exchanger module

The performance of blood-processing devices largely depends on the associated fluid dynamics, which hence represents a key aspect in their design and optimization. To this aim, two approaches are currently adopted: computational fluid-dynamics, which yields highly resolved three-dimensional data but relies on simplifying assumptions, and in vitro experiments, which typically involve the direct video-acquisition of the flow field and provide 2D data only. We propose a novel method that exploits space- and time-resolved magnetic resonance imaging (4D-flow) to quantify the complex 3D flow field in blood-processing devices and to overcome these limitations.We tested our method on a real device that integrates an oxygenator and a heat exchanger. A dedicated mock loop was implemented, and novel 4D-flow sequences with sub-millimetric spatial resolution and region-dependent velocity encodings were defined. Automated in house software was developed to quantify the complex 3D flow field within the different regions of the device: region-dependent flow rates, pressure drops, paths of the working fluid and wall shear stresses were computed.Our analysis highlighted the effects of fine geometrical features of the device on the local fluid-dynamics, which would be unlikely observed by current in vitro approaches. Also, the effects of non-idealities on the flow field distribution were captured, thanks to the absence of the simplifying assumptions that typically characterize numerical models.To the best of our knowledge, our approach is the first of its kind and could be extended to the analysis of a broad range of clinically relevant devices.     

Causes of slowing‐down seasonal CO2 amplitude at Mauna Loa

Changing amplitude of the seasonal cycle of atmospheric CO₂ (SCA) in the northern hemisphere is an emerging carbon cycle property. Mauna Loa (MLO) station (20°N, 156°W), which has the longest continuous northern hemisphere CO₂ record, shows an increasing SCA before the 1980s (p < .01), followed by no significant change thereafter. We analyzed the potential driving factors of SCA slowing‐down, with an ensemble of dynamic global vegetation models (DGVMs) coupled with an atmospheric transport model. We found that slowing‐down of SCA at MLO is primarily explained by response of net biome productivity (NBP) to climate change, and by changes in atmospheric circulations. Through NBP, climate change increases SCA at MLO before the 1980s and decreases it afterwards. The effect of climate change on the slowing‐down of SCA at MLO is mainly exerted by intensified drought stress acting to offset the acceleration driven by CO₂ fertilization. This challenges the view that CO₂ fertilization is the dominant cause of emergent SCA trends at northern sites south of 40°N. The contribution of agricultural intensification on the deceleration of SCA at MLO was elusive according to land–atmosphere CO₂ flux estimated by DGVMs and atmospheric inversions. Our results also show the necessity to adequately account for changing circulation patterns in understanding carbon cycle dynamics observed from atmospheric observations and in using these observations to benchmark DGVMs.