N-Cadherin-Expressing Bone and Marrow Stromal Progenitor Cells Maintain Reserve Hematopoietic Stem Cells

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鄂西南三个自然保护区蚁科昆虫的区系调查

星斗山自然保护区、木林子自然保护区和坪坝营自然保护区地处湖北省西南山区,地形地貌复杂,属大陆性中亚热带季风湿润气候,昆虫资源十分丰富,作者首次报道这3个自然保护区蚂蚁的种类和分布。结果表明3个自然保护区共有蚂蚁53种,隶属于5亚科,22属。在区系组成上,东洋界种类25种,占全部种类的47.1%,东洋界和古北界均有分布的种类22种,占41.5%,古北种和特有种各有3种,分别占5.6%。说明3个自然保护区的蚂蚁以东洋界为主。并分析了3个自然保护区蚂蚁的分布特征。     

气候变化对亚热带常绿阔叶林优势类群樟属植物的影响及保护评估

常绿阔叶林的优势类群由于其个体数量多、盖度大、生物量高、生存能力强, 对维持相应生态系统的稳定起着主导作用。樟属(Cinnamomum)植物为亚热带常绿阔叶林的优势类群, 通过对其过去、当前和未来潜在分布区的研究可以了解该类群的变迁历史, 为理解亚热带常绿阔叶林动态变化提供帮助, 有助于亚热带常绿阔叶林保育策略的制定。本研究利用最大熵(MaxEnt)模型模拟了我国樟属47种植物在5个时期(末次间冰期、末次盛冰期、全新世中期、当前和未来)的潜在分布区及物种丰富度热点区域。此外, 根据樟属植物的物种丰富度热点区域与自然保护区相叠加, 对当前自然保护区的保护状态进行了评估, 尤其是为保护亚热带常绿阔叶林而设立的自然保护区。结果表明: 樟属物种的潜在分布区在5个时期变化均不大, 仅在亚热带-温带交界处的各大山脉和平原之间出现局部收缩和扩张; 值得注意的是, 物种丰富度热点区域在5个时期变化明显, 末次盛冰期面积最大, 相较于末次间冰期、全新世中期和当前分别多96%、88%和37%; 未来(~2080年)两种不同温室气体排放典型浓度途径(representative concentration pathways, RCP) (RCP2.6和RCP8.5)下, 樟属物种丰富度热点区域面积将分别比当前收缩8.4%和10.0%, 并且随着温室气体排放的增加, 物种热点区域收缩趋势会更加明显。此外, 本研究发现樟属物种丰富度热点区域主要位于我国四川东南部、贵州南部、广西和广东, 然而仅7.5%位于现有自然保护区内, 未来自然保护区、国家公园等自然保护地的扩建、选址和规划应优先考虑四川东南部和华南地区。     

Coronary physiology before and after chronic total occlusion treatment: what does it tell us?

Studies performed in the last two decades demonstrate that after successful percutaneous coronary intervention (PCI) of a chronically occluded coronary artery, the physiology of the chronic total occlusion (CTO) vessel and dependent microvasculature does not normalise immediately but improves significantly over time. Generally, there is an increase in fractional flow reserve (FFR) in the CTO artery, a decrease in collateral blood supply and an increase in FFR in the donor artery accompanied by an increase in blood flow and decrease in microvascular resistance in the myocardium supplied by the CTO vessel. Analogous to these physiological changes, positive remodelling of the distal CTO artery also occurs over time, and intravascular imaging can be helpful for analysing distal vessel parameters. Follow-up coronary angiography with physiological measurements after several weeks to months can be helpful and informative in a subset of patients in order to decide upon the necessity for treatment of residual coronary artery stenosis in the vessel distal to the CTO or in the contralateral donor artery, as well as in deciding whether stent optimisation is indicated. We suggest that such physiological guidance of CTO procedures avoids unnecessary overtreatment during the initial procedure, guides interventions at follow-up, and improves our understanding of what PCI in CTO means.

     

Integrating scientific guidance into marine spatial planning

Marine spatial planning (MSP), whereby areas of the ocean are zoned for different uses, has great potential to reduce or eliminate conflicts between competing management goals, but only if strategically applied. The recent literature overwhelmingly agrees that including stakeholders in these planning processes is critical to success; but, given the countless alternative ways even simple spatial regulations can be configured, how likely is it that a stakeholder-driven process will generate plans that deliver on the promise of MSP? Here, we use a spatially explicit, dynamic bioeconomic model to show that stakeholder-generated plans are doomed to fail in the absence of strong scientific guidance. While strategically placed spatial regulations can improve outcomes remarkably, the vast majority of possible plans fail to achieve this potential. Surprisingly, existing scientific rules of thumb do little to improve outcomes. Here, we develop an alternative approach in which models are used to identify efficient plans, which are then modified by stakeholders. Even if stakeholders alter these initial proposals considerably, results hugely outperform plans guided by scientific rules of thumb. Our results underscore the importance of spatially explicit dynamic models for the management of marine resources and illustrate how such models can be harmoniously integrated into a stakeholder-driven MSP process.     

The severity of coronary artery disease and reversible ischemia revealed by N-terminal pro-brain natriuretic peptide in patients with unstable angina and preserved left ventricular function

The association between the levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) and the severity of coronary artery disease (CAD) diagnosed by coronary angiography and other approaches has been investigated. The clinical application of NT-proBNP is restricted by the drawbacks of these techniques now available in screening out patients who need intensive or conservative treatment. Fractional flow reserve (FFR) is superior to coronary angiography and other functional indicators. Accordingly, we designed to investigate the association between NT-proBNP and myocardial ischemia from the perspective of anatomy and physiology in patients with unstable angina and preserved left ventricular function. Plasma samples were collected from 110 patients and NT-proBNP levels were measured by radioimmunoassay. The severity of coronary artery stenosis in patients was measured by coronary angiography and FFR. Stenosis ≥50% in the left main artery or stenosis of 70%, and fractional flow reserve (FFR) ≤0.80 in one or more coronary branches with diameter ≥2 mm were defined as “positive”, which require revascularization. NT-proBNP levels increased progressively between patients with negative and positive angiographic results (p < 0.05), and between FFR-negative and FFR-positive patients (p < 0.05). A significant correlation was observed between log NT-proBNP and log GS (GS = Gensini score, p < 0.001). NT-proBNP level serves as a predictor of positive results of angiographic stenosis and FFR, with the area under the receiver operating characteristic curve being 0.697 and 0.787, respectively. NT-proBNP levels are correlated with the severity of anatomic coronary obstruction and inducible myocardial ischemia, but NT-proBNP per se is insufficient to identify clinically significant angiographic and physiological stenoses.     

Main plant communities and characteristics of Kalamaili Ungulate Nature Reserve in east Junggar Basin

The main vegetation types of Kalamaili Nature Reserve in east Junggar Basin were investigated in this paper, and based on the data from 54 plot samples, the characteristics of the main desert plant communities from the main vegetation types were quantitatively described. And the results showed that, the vegetation in this reserve can be divided in to 9 major desert plant community types were recognized: Form. Haloxylon ammodendron, Form. Krascheninnikovia ceratoides, Form. Atraphaxis spinosa, Form. Reaumuria songarica, Form. Artemisia songarica, Form. Convolvulus tragacanthoides, Form. Anabasis salsa, Form. Stipa glareosa and Form. Seriphidium terrae-albae, and then, 16 associations were divided from these 9 major community types.     

Biodiversity monitoring by community‐based restoration groups in New Zealand

In recent decades, community groups have transformed habitat restoration, pest control and species translocations in New Zealand. Large areas of wild New Zealand benefit hugely from ongoing management by community‐based restoration groups. Areas near cities and towns have especially good access to pools of keen volunteers. Community groups are involved in monitoring progress with their work, as well as monitoring biodiversity changes in general at their project sites. New tools powered by modern technologies are creating the opportunity for New Zealand's community volunteers to play a transformative role in biodiversity monitoring for either purpose. These tools are reducing the resources and expertise required for species detection and identification. Smartphones with cameras, GPS, audio recorders and data apps make it easier than ever to record species observations. Crowd‐sourced identification of species in photographs and sounds loaded onto NatureWatch NZ allow volunteers to make observations of a much wider range of taxa than just common birds and trees. Realising this potential requires community groups, scientists and their institutions to collaborate in building and maintaining simple, accessible monitoring systems that (i) require and promote standard monitoring methods, (ii) provide efficient data entry in standard formats, (iii) generate automated results of use to community groups and (iv) facilitate public sharing of data to contribute to regional, national and global biodiversity monitoring. Some New Zealand monitoring systems developed recently to assist community‐based restoration groups with monitoring mammalian predator control are good examples of this approach. Making this happen at a large scale across many community groups and taxa requires increased and coordinated long‐term institutional support for monitoring systems and training.     

Cheater or mutualist? Novel florivory interaction between nectar‐rich Crotalaria cunninghamii and small mammals

Animals visit flowers to access resources and by moving pollen to conspecific individuals act as pollinators. While biotic pollinators can increase the seed set of plants, other flower visitors can reduce seed set directly by damaging vital reproductive organs and indirectly by affecting the way the plant interacts with subsequent flower visitors. It is, therefore, vital to understand the varied effects of all visitors and not only pollinators on plant fitness, including those visitors that are temporally or spatially rare. We document the first known case of flower visitation by small mammals to Crotalaria cunninghamii (Fabaceae), a plant species morphologically suited to bird pollination. During a rain‐driven resource pulse in the Simpson Desert in 2011, the rodents Mus musculus (Muridae) and Pseudomys hermannsburgensis (Muridae) visited flowers to remove nectar by puncturing the calyx. We investigated the effects of this novel interaction on the reproductive output of C. cunninghamii. Compared with another recent resource pulse in 2007, plants flowering during mammal visitation had five times as many inflorescences per plant, 90% more flowers per inflorescence, and two to three times more nectar per flower, but this nectar was 30% less sugar rich. Concurrently, rodent plagues were up to three times larger during this rain‐driven resource pulse than during a previous pulse in 2007. Up to 75% of flowers had evidence of small mammal florivory, but this was not necessarily destructive, as up to 90% of fruit had the remains of florivory. Through a series of exclusion experiments, we found that small mammal florivory did not directly reduce seed set. We conclude that rain‐driven resource pulses led to a unique combination of events that facilitated the novel florivory interaction. Our findings emphasize the dynamic nature of biotic interactions and the importance of testing the role of all visitors to pollination services.     

Menin expression modulates mesenchymal cell commitment to the myogenic and osteogenic lineages

Menin plays an established role in the differentiation of mesenchymal cells to the osteogenic lineage. Conversely, whether Menin influences the commitment of mesenschymal cells to the myogenic lineage, despite expression in the developing somite was previously unclear. We observed that Menin is down-regulated in C2C12 and C3H10T1/2 mesenchymal cells when muscle differentiation is induced. Moreover, maintenance of Menin expression by constitutive ectopic expression inhibited muscle cell differentiation. Reduction of Menin expression by siRNA technology results in precocious muscle differentiation and concomitantly attenuates BMP-2 induced osteogenesis. Reduced Menin expression antagonizes BMP-2 and TGF-β1 mediated inhibition of myogenesis. Furthermore, Menin was found to directly interact with and potentiate the transactivation properties of Smad3 in response to TGF-β1. Finally in concert with these observations, tissue-specific inactivation of Men1 in Pax3-expressing somite precursor cells leads to a patterning defect of rib formation and increased muscle mass in the intercostal region. These data invoke a pivotal role for Menin in the competence of mesenchymal cells to respond to TGF-β1 and BMP-2 signals. Thus, by modulating cytokine responsiveness Menin functions to alter the balance of multipotent mesenchymal cell commitment to the osteogenic or myogenic lineages.