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961.
Recent studies have detected phylogenetic signals in pathogen–host networks for both soil‐borne and leaf‐infecting fungi, suggesting that pathogenic fungi may track or coevolve with their preferred hosts. However, a phylogenetically concordant relationship between multiple hosts and multiple fungi in has rarely been investigated. Using next‐generation high‐throughput DNA sequencing techniques, we analyzed fungal taxa associated with diseased leaves, rotten seeds, and infected seedlings of subtropical trees. We compared the topologies of the phylogenetic trees of the soil and foliar fungi based on the internal transcribed spacer (ITS) region with the phylogeny of host tree species based on matK, rbcL, atpB, and 5.8S genes. We identified 37 foliar and 103 soil pathogenic fungi belonging to the Ascomycota and Basidiomycota phyla and detected significantly nonrandom host–fungus combinations, which clustered on both the fungus phylogeny and the host phylogeny. The explicit evidence of congruent phylogenies between tree hosts and their potential fungal pathogens suggests either diffuse coevolution among the plant–fungal interaction networks or that the distribution of fungal species tracked spatially associated hosts with phylogenetically conserved traits and habitat preferences. Phylogenetic conservatism in plant–fungal interactions within a local community promotes host and parasite specificity, which is integral to the important role of fungi in promoting species coexistence and maintaining biodiversity of forest communities. 相似文献
962.
Massimiliano Carnabuci Giulia Schiavon Michela Bellingeri Fulvio Fossa Chiara Paoli Paolo Vassallo Guido Gnone 《Population Ecology》2016,58(2):249-264
The bottlenose dolphin (Tursiops truncatus Montagu, 1821) is a regularly observed species in the Mediterranean Sea, but its network organization has never been investigated on a large scale. We described the network macrostructure of the bottlenose dolphin (meta)population inhabiting the Pelagos Sanctuary (a wide protected area located in the north-western portion of the Mediterranean basin) and we analysed its connectivity in relation to the landscape traits. We pooled effort and sighting data collected by 13 different research institutions operating within the Pelagos Sanctuary from 1994 to 2011 to examine the distribution of bottlenose dolphins in the Pelagos study area and then we applied a social network analysis, investigating the association patterns of the photo-identified dolphins (806 individuals in 605 sightings). The bottlenose dolphin (meta)population inhabiting the Pelagos Sanctuary is clustered in discrete units whose borders coincide with habitat breakages. This complex structure seems to be shaped by the geo-morphological and ecological features of the landscape, through a mechanism of local specialization of the resident dolphins. Five distinct clusters were identified in the (meta)population and two of them were solid enough to be further investigated and compared. Significant differences were found in the network parameters, suggesting a different social organization of the clusters, possibly as a consequence of the different local specialization. 相似文献
963.
Species roles in ecological networks combine to generate their architecture, which contributes to their stability. Species trait diversity also affects ecosystem functioning and resilience, yet it remains unknown whether species’ contributions to functional diversity relate to their network roles. Here, we use 21 empirical pollen transport networks to characterise this relationship. We found that, apart from a few abundant species, pollinators with original traits either had few interaction partners or interacted most frequently with a subset of these partners. This suggests that narrowing of interactions to a subset of the plant community accompanies pollinator niche specialisation, congruent with our hypothesised trade‐off between having unique traits vs. being able to interact with many mutualist partners. Conversely, these effects were not detected in plants, potentially because key aspects of their flowering traits are conserved at a family level. Relating functional and network roles can provide further insight into mechanisms underlying ecosystem functioning. 相似文献
964.
Juan Pablo Niño‐García Clara Ruiz‐González Paul A. del Giorgio 《Ecology letters》2016,19(12):1506-1515
Aquatic bacterial communities harbour thousands of coexisting taxa. To meet the challenge of discriminating between a ‘core’ and a sporadically occurring ‘random’ component of these communities, we explored the spatial abundance distribution of individual bacterioplankton taxa across 198 boreal lakes and their associated fluvial networks (188 rivers). We found that all taxa could be grouped into four distinct categories based on model statistical distributions (normal like, bimodal, logistic and lognormal). The distribution patterns across lakes and their associated river networks showed that lake communities are composed of a core of taxa whose distribution appears to be linked to in‐lake environmental sorting (normal‐like and bimodal categories), and a large fraction of mostly rare bacteria (94% of all taxa) whose presence appears to be largely random and linked to downstream transport in aquatic networks (logistic and lognormal categories). These rare taxa are thus likely to reflect species sorting at upstream locations, providing a perspective of the conditions prevailing in entire aquatic networks rather than only in lakes. 相似文献
965.
Qize Lv;Ke Liang;ChongXuan Tian;YanHai Zhang;YunZe Li;JinLin Deng;WeiMing Yue;Wei Li; 《Journal of biophotonics》2024,17(11):e202400325
Thymoma, a rare tumor from thymic epithelial cells, presents diagnostic challenges because of the subjective nature of traditional methods, leading to high false-negative rates and long diagnosis times. This study introduces a thymoma classification technique that integrates hyperspectral imaging with deep learning. We initially capture pathological slice images of thymoma using a hyperspectral camera and delineate regions of interest to extract spectral data. This data undergoes reflectance calibration and noise reduction. Subsequently, we transform the spectral data into two-dimensional images via the Gramian Angular Field (GAF) method. A variant residual network is then utilized to extract features and classify these images. Our results demonstrate that this model significantly enhances classification accuracy and efficiency, achieving an average accuracy of 95%. The method proves highly effective in automated thymoma diagnosis, optimizing data utilization, and feature representation learning. 相似文献
966.
Ji Guo Su Xiao Ming Han Xiao Zhang Yan Xue Hou Jian Zhuo Zhu Yi Dong Wu 《Journal of biomolecular structure & dynamics》2016,34(3):560-571
Protein collective motions play a critical role in many biochemical processes. How to predict the functional motions and the related key residue interactions in proteins is important for our understanding in the mechanism of the biochemical processes. Normal mode analysis (NMA) of the elastic network model (ENM) is one of the effective approaches to investigate the structure-encoded motions in proteins. However, the motion modes revealed by the conventional NMA approach do not necessarily correspond to a specific function of protein. In the present work, a new analysis method was proposed to identify the motion modes responsible for a specific function of proteins and then predict the key residue interactions involved in the functional motions by using a perturbation approach. In our method, an internal coordinate that accounts for the specific function was introduced, and the Cartesian coordinate space was transformed into the internal/Cartesian space by using linear approximation, where the introduced internal coordinate serves as one of the axes of the coordinate space. NMA of ENM in this internal/Cartesian space was performed and the function-relevant motion modes were identified according to their contributions to the specific function of proteins. Then the key residue interactions important for the functional motions of the protein were predicted as the interactions whose perturbation largely influences the fluctuation along the internal coordinate. Using our proposed methods, the maltose transporter (MalFGK2) from E. Coli was studied. The functional motions and the key residue interactions that are related to the channel-gating function of this protein were successfully identified. 相似文献
967.
The phosphatase and tensin homolog deleted on chromosome ten (PTEN) gene encodes a tumor suppressor phosphatase that has recently been found to be frequently mutated in patients with endometriosis, endometrial cancer and ovarian cancer. Here, we present the first computational analysis of 13 somatic missense PTEN mutations associated with these phenotypes. We found that a majority of the mutations are associated in conserved positions within the active site and are clustered within the signature motif, which contain residues that play a crucial role in loop conformation and are essential for catalysis. In silico analyses were utilized to identify the putative effects of these mutations. In addition, coarse‐grained models of both wild‐type (WT) PTEN and mutants were constructed using elastic network models to explore the interplay of the structural and global dynamic effects that the mutations have on the relationship between genotype and phenotype. The effects of the mutations reveal that the local structure and interactions affect polarity, protein structure stability, electrostatic surface potential, and global dynamics of the protein. Our results offer new insight into the role in which PTEN missense mutations contribute to the molecular mechanism and genotypic‐phenotypic correlation of endometriosis, endometrial cancer, and ovarian cancer. Proteins 2016; 84:1625–1643. © 2016 Wiley Periodicals, Inc. 相似文献
968.
Oi Omotuyi 《Molecular simulation》2016,42(11):874-881
S100A13 is S100 family of EF-hand-containing calcium-binding protein involved in the secretion of some growth factors and pro-inflammatory cytokines lacking signal peptides. The involvement of S100A13 in cancer progression and inflammatory diseases has been reported. In this study, structures generated during atomistic molecular dynamics simulation were studied. Dynamical network analysis data revealed that native inter-protomer communication network driven principally by vdW interaction (~550 kj/mol) is altered (Receptor for advanced glycation end products (RAGE) C2- and Fibroblast growth factor (FGF)-1-bound S100A13) or completely abolished (interleukin-1 (IL1)-α- and C2A-p40Syt1-bound S100A13) in protein-bound S100A13 homodimer. Bulk water density (weighted atomic density) around exposed S100A13 homodimer surface explored tends to follow the dynamical network lead as S100A13 homodimer appeared densely solvated in C2A-p40Syt1- and IL1)-α-bound states but not in RAGE C2- and FGF-1-bound biosystems. Furthermore, projection of radius of gyration and root mean square deviation (from native structure) variables of the generated structures along the 3D-free energy surface showed anti-parallel β-sheet proximal to Ca2+-binding loops-I/II in most metastable complexes retrieved from energy minima state with strong indications for β-sheet network formation during protein binding. Interaction between S100A13 homodimer and ligand–proteins may be dictated by the strength of vdW and electrostatic interaction with possible involvement of bulk water desolvation in some complexes. All these results strongly suggest that disruption of multiprotein receptor complex can be achieved by designing specific compounds targeting a specific aspect of S100A13/protein interaction; such drugs may have clinical usefulness in blocking angiogenesis, reversing cell proliferation and attenuating inflammatory processes. 相似文献
969.
目的 分析高血压患者在农村医疗服务网络接受协调性和连续性服务的提供状况,为改进患者的整合服务利用提供决策参考。方法 根据国内外文献,以自行编制服务协调性和连续性提供的问卷为工具,调查数据采用描述性统计分析。结果 49.6%的患者伴有1种及以上疾病,约73.0%在乡镇卫生院有就医经历,到过2家及以上机构就医的占51.3%;在乡村两级治疗效果不佳的患者,能够获取村医和乡镇医生推荐转诊机构的比重最大,分别为28.4%和68.7%;上级医生能够根据下级机构相关诊疗信息连续诊疗的不到43.0%,下级医生能够根据前期诊疗信息继续诊疗的比例刚超4成;“上转容易、下转难”现象同样存在。 结论 农村慢性病患者的患病特点增加了在农村纵向医疗机构就诊的几率,但该网络提供连续性和协调性服务的程度却不高,应加强农村三级医疗机构间的全面整合。 相似文献
970.