Sensitive Chemiluminescence Enzyme Immunoassay for Vascular Endothelial Growth Factor/Vascular Permeability Factor in Human Serum

A sandwich chemiluminescence enzyme immunoassay for measuring the level of VEGF /VPF in serum was constructed. The detectability of the assay is very low (1.0pg/ml) and the measurable range of the assay was very wide (1–1000 pg/ml). The assay showed that the average level of VEGF /VPF in human sera from healthy blood donors was approximately 19 pg/ml.     

The method matters: A guide for indicator aggregation in ecological assessments

Ecological assessment requires the integration of many physical, chemical, and/or biological quality elements. The choice of the aggregation method of such partial assessments into an overall assessment can considerably affect the assessment outcome – an issue that has been controversially discussed within the scientific community for the last decade. Current practice often considers only two different aggregation methods, the weighted arithmetic mean (additive aggregation) and the one-out, all-out method (minimum aggregation). However, both have important drawbacks. Additive aggregation compensates a bad status of one quality element by a number of elements featuring good status. Minimum aggregation can lead to overly pessimistic assessment results, since only the quality element in the worst status is considered. Here, we introduce a toolbox containing current and new aggregation methods, demonstrate and discuss their properties with simple, didactical examples, and suggest in which situations best to use them. Then, we illustrate the consequences of selected aggregation schemes for ecological river assessment with the case study of the Swiss Modular Concept of stream assessment (SMC), which we apply to ten river reaches in the Mönchaltdorfer Aa catchment in Switzerland. To be able to do so, we used multi-criteria decision analysis, i.e., multi-attribute value theory, to arrange the SMC quality elements into an objectives hierarchy, and to translate their individual assessments into value functions. Our case study revealed that choosing the most appropriate aggregation method particularly matters, if objectives with significantly different qualities are aggregated. We argue that redundant objectives (i.e., quality elements), often found at the lower levels of the objectives hierarchy, should best be aggregated additively allowing for compensation to increase the statistical significance of the results. Further, we suggest that complementary sub-objectives that often occur at higher levels may be optimally aggregated with a mixture of additive and minimum aggregation. Such a mixed method will allow some compensation, but nevertheless penalize for very bad states. Since here we compare commonly used aggregation methods with some which we believe have never been discussed in an assessment context before, our study concurrently informs ecological assessment in theory and in practice.     

HGT is widespread in insects and contributes to male courtship in lepidopterans

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野生田头菇菌株的驯化及其子实体营养成分分析

采自湖南洞庭湖大通湖区芦苇湿地的野生菌株,经鉴定为田头菇Agrocybe praecox。通过驯化实现人工栽培,栽培原料以芦苇屑为主,使用液体菌种和覆土栽培方式,初潮菇平均生物转化率为45.6%。营养成分分析表明：以芦苇屑为栽培培养基,子实体中矿物元素含量分别为K（2 190mg/kg）、Fe（16.2mg/kg）、Mg（59.7mg/kg）、Ca（33.4mg/kg）,必需氨基酸含量占比高达44.85%,谷氨酸、蛋氨酸、天冬氨酸含量高,是一种高蛋白、低脂肪、高钾低钠的食用菌。     

虎杖象甲培植真菌营养特性及对菌丝附属物形成的影响

虎杖象甲培植共生真菌形成的共生体系是植菌昆虫菌业中的典型代表。共生真菌Penicillium herquei如何向虎杖象甲Euops chinensis提供营养尚未明确。本研究发现共生真菌P. herquei的菌丝表面存在大量瘤状凸起物及由凸起物衍生的附属丝等特化结构,该结构可能为虎杖象甲提供营养;对共生真菌的营养研究表明,共生真菌能高效利用山梨醇、蔗糖、海藻糖、葡萄糖等单糖或双糖,以及酪氨酸、甘氨酸、谷氨酰胺等昆虫非必须氨基酸,同时在高碳和最适碳源条件下有利于菌丝特化附属物的产生。研究结果不仅提供了植菌卷叶象甲菌业中共生真菌在营养方面的适应性进化证据,而且为进一步揭示共生真菌适应卷叶象甲的营养机制奠定了基础。     

持续颅内压监测对大面积脑梗死外科治疗预后的应用价值

目的:探讨持续颅内压(ICP)监测对大面积脑梗死外科治疗预后的应用价值。方法:选取2013年3月至2018年3月期间在我院接受治疗的大面积脑梗死患者100例作为研究对象,所有患者经去骨瓣减压术后行ICP监测和生命体征监测,通过结果分为:低压组62例(2.70kPa≤ICP5.30kPa),高压组38例(ICP≥5.30 kPa)。记录患者ICP监测数值,接收者操作特征(ROC)曲线分析患者预后情况,对患者进行术后3个月内随访,了解患者平常活动能力进行判断预后的状况。观察ICP与预后的相关性。结果:两组患者性别、年龄、室速、室性早搏、糖尿病、高血压病、脑卒中、高脂血症、风心病、冠心病、扩张性心肌病、既往心肌梗死、肥厚性心肌病、甲亢性心脏病等资料比较差异无统计学意义(P0.05)。低压组患者中预后良好的ICP监测值显著低于预后不良者(P0.05),高压组中预后良好的ICP监测值显著低于预后不良者(P0.05)。ICP预测大面积脑梗死外科治疗预后的ROC曲线面积0.704,采用最大约等指数计算得出ICP预测大面积脑梗死外科治疗预后的最大AUC面积相应参数截止值为4.89,其中敏感度为0.435,特异性为0.896。结论:持续ICP监测结果显示ICP值越小,患者的预后就越好,ICP值越高,患者的预后越差。ICP监测对大面积脑梗死外科治疗的预后具有预测价值,对判断和改善预后能起到有效帮助,值得在临床推广应用。     

Early vigour in wheat: Could it lead to more severe terminal drought stress under elevated atmospheric [CO2] and semi‐arid conditions?

Early vigour in wheat is a trait that has received attention for its benefits reducing evaporation from the soil surface early in the season. However, with the growth enhancement common to crops grown under elevated atmospheric CO₂ concentrations (e[CO₂]), there is a risk that too much early growth might deplete soil water and lead to more severe terminal drought stress in environments where production relies on stored soil water content. If this is the case, the incorporation of such a trait in wheat breeding programmes might have unintended negative consequences in the future, especially in dry years. We used selected data from cultivars with proven expression of high and low early vigour from the Australian Grains Free Air CO₂ Enrichment (AGFACE) facility, and complemented this analysis with simulation results from two crop growth models which differ in the modelling of leaf area development and crop water use. Grain yield responses to e[CO₂] were lower in the high early vigour group compared to the low early vigour group, and although these differences were not significant, they were corroborated by simulation model results. However, the simulated lower response with high early vigour lines was not caused by an earlier or greater depletion of soil water under e[CO₂] and the mechanisms responsible appear to be related to an earlier saturation of the radiation intercepted. Whether this is the case in the field needs to be further investigated. In addition, there was some evidence that the timing of the drought stress during crop growth influenced the effect of e[CO₂] regardless of the early vigour trait. There is a need for FACE investigations of the value of traits for drought adaptation to be conducted under more severe drought conditions and variable timing of drought stress, a risky but necessary endeavour.     

The genetics of evolutionary radiations

With the realization that much of the biological diversity on Earth has been generated by discrete evolutionary radiations, there has been a rapid increase in research into the biotic (key innovations) and abiotic (key environments) circumstances in which such radiations took place. Here we focus on the potential importance of population genetic structure and trait genetic architecture in explaining radiations. We propose a verbal model describing the stages of an evolutionary radiation: first invading a suitable adaptive zone and expanding both spatially and ecologically through this zone; secondly, diverging genetically into numerous distinct populations; and, finally, speciating. There are numerous examples of the first stage; the difficulty, however, is explaining how genetic diversification can take place from the establishment of a, presumably, genetically depauperate population in a new adaptive zone. We explore the potential roles of epigenetics and transposable elements (TEs), of neutral process such as genetic drift in combination with trait genetic architecture, of gene flow limitation through isolation by distance (IBD), isolation by ecology and isolation by colonization, the possible role of intra‐specific competition, and that of admixture and hybridization in increasing the genetic diversity of the founding populations. We show that many of the predictions of this model are corroborated. Most radiations occur in complex adaptive zones, which facilitate the establishment of many small populations exposed to genetic drift and divergent selection. We also show that many radiations (especially those resulting from long‐distance dispersal) were established by polyploid lineages, and that many radiating lineages have small genome sizes. However, there are several other predictions which are not (yet) possible to test: that epigenetics has played a role in radiations, that radiations occur more frequently in clades with small gene flow distances, or that the ancestors of radiations had large fundamental niches. At least some of these may be testable in the future as more genome and epigenome data become available. The implication of this model is that many radiations may be hard polytomies because the genetic divergence leading to speciation happens within a very short time, and that the divergence history may be further obscured by hybridization. Furthermore, it suggests that only lineages with the appropriate genetic architecture will be able to radiate, and that such a radiation will happen in a meta‐population environment. Understanding the genetic architecture of a lineage may be an essential part of accounting for why some lineages radiate, and some do not.