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The effects of β adrenergic receptors (β‐ARs) and p38 mitogen‐activated protein kinases (MAPK) pathways on cardiosphere‐derived cells (CDCs) are largely unknown. This study aimed to investigate the roles of β‐ARs and p38MAPK pathways on the proliferation, apoptosis, and differentiation capacity of CDCs. The CDCs were treated with β1‐AR blocker (Met group), β2‐AR antagonist (ICI group), and p38MAPK inhibitor (SB group), non‐selective β‐AR blocker (PRO group), and β‐AR agonist (ISO group). The viability, apoptotic rate and differentiation status of CDCs were determined by MST‐1 assay, flow cytometery, and Western blot, respectively. The CDCs viability significantly reduced in ICI group (all P < 0.05), and SB group had a significant high viability after 48 h treatment (P < 0.05). Compared with control group, all treated groups had a low apoptotic rate. After treatment for 72 h, ISO treatment elevated the expression of Nkx2.5, and could partially or fully attenuate the inhibitory effects of β‐AR antagonists and/or p38MAPK inhibitor. A similar overall trend of protein expression levels among all groups could be observed between protein pairs of cTnT and β1‐AR as well as c‐Kit and β2‐AR, respectively. These results suggested that β‐ARs and p38MAPK signaling pathways play crucial roles in the proliferation and differentiation of CDCs. Our findings should be helpful for better understanding the molecular mechanism underlying the physiological processes of CDCs.  相似文献   
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Yunnanopilia longistaminea (W.Z. Li) C.Y. Wu & D.Z. Li, which is a controversial species in Opiliaceae, is treated as a variety of Champereia manillana (Blume) Merrill in the Flora of China and morphological analysis has produced conflicting results regarding its affinity to Melientha and Champereia. To determine the systematic position of Yunnanopilia in Opiliaceae, we selected two nuclear regions (internal transcribed spacer [ITS4‐ITS5] and 18S rDNA) and four chloroplast regions (rbcL, matK, psbAtrnH, and trnStrnG) to test the phylogenetics of the family Opiliaceae using maximum likelihood and Bayesian inference analysis. Morphological characteristics were also examined to clarify the similarities and differences among Y. longistaminea and two closely related species. Agonandra was located at the basal position in the family Opiliaceae; in the large clade including other remaining genera, two main clades were clearly identified and correlated with inflorescence morphological characteristics. All samples of Y. longistaminea formed a clade. Yunnanopilia, Melientha, and Champereia were more closely related than other genera of Opiliaceae. Yunnanopilia longistaminea was sister to M. suavis Pierre and was more closely related to M. suavis than to C. manillana. Morphological analysis also showed that differences in the inflorescences and flowers between Y. longistaminea and M. suavis were substantial enough to warrant the retention of Y. longistaminea in its current genus. Thus, we suggest that the monotypic Yunnanopilia be treated as a distinct genus and that the name Y. longistaminea should be adopted.  相似文献   
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SECTR is a novel multimodal imaging platform for combined volumetric optical coherence tomography (OCT) and en face spectrally encoded reflectometry (SER). The authors demonstrate three‐dimensional motion‐tracking with millisecond temporal and micron spatial resolution using complementary data from OCT and SER, and preliminary algorithms and results showing real‐time image aiming and multi‐volumetric mosaicking for reconstruction of wide‐field composites. The image shows a noninvasively imaged nine‐field mosaic of in vivo human retina and depth‐resolved visualization of tissue microstructures. Further details can be found in the article by Mohamed T. El‐Haddad, Ivan Bozic, and Yuankai K. Tao ( e201700268 )

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The extent of the effect of projected changes in climate on trees remains unclear. This study investigated the effect of climatic variation on morphological traits of balsam fir [Abies balsamea (L.) Mill.] provenances sourced from locations spanning latitudes from 44° to 51°N and longitudes from 53° to 102°W across North America, growing in a common garden in eastern Canada. Lower latitude provenances performed significantly better than higher latitude provenances (p < .05) with regard to diameter at breast height (DBH), height (H), and crown width (CW), a distinction indicative of genotypic control of these traits. There was, however, no significant difference among provenances in terms of survival (> .05), an indication of a resource allocation strategy directed at survival relative to productivity in higher latitude provenances as seen in their lower DBH, H, and CW compared to the lower latitude provenances. Temperature had a stronger relationship with DBH, H, and CW than precipitation, a reflection of adaptation to local conditions in populations of the species along latitudinal gradients. Both climatic variables had some effect on tree survival. These results suggest that the response of balsam fir to climatic variation will likely not be uniform in the species, but differ based on genetic characteristics between populations located in the northern and southern parts of the species’ range. Population differences in response to climatic variation may be evident earlier in growth traits, compared to survival in balsam fir. The findings of this study will facilitate modeling in the species that is reflective of genetic variation in response to climatic conditions, and guide provenance selection for utilization in terms of productivity or resilience as well as breeding programs directed at obtaining species that possibly combine both traits.  相似文献   
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Expansion of oil palm agriculture is currently one of the main drivers of habitat modification in Southeast Asia. Habitat modification can have significant effects on biodiversity, ecosystem function, and interactions between species by altering species abundances or the available resources in an ecosystem. Increasing complexity within modified habitats has the potential to maintain biodiversity and preserve species interactions. We investigated trophic interactions between Argyrodes miniaceus, a cleptoparasitic spider, and its Nephila spp. spider hosts in mature oil palm plantations in Sumatra, Indonesia. A. miniaceus co‐occupy the webs of Nephila spp. females and survive by stealing prey items caught in the web. We examined the effects of experimentally manipulated understory vegetation complexity on the density and abundance of A. miniaceus in Nephila spp. webs. Experimental understory treatments included enhanced complexity, standard complexity, and reduced complexity understory vegetation, which had been established as part of the ongoing Biodiversity and Ecosystem Function in Tropical Agriculture (BEFTA) Project. A. miniaceus density ranged from 14.4 to 31.4 spiders per square meter of web, with significantly lower densities found in reduced vegetation complexity treatments compared with both enhanced and standard treatment plots. A. miniaceus abundance per plot was also significantly lower in reduced complexity than in standard and enhanced complexity plots. Synthesis and applications: Maintenance of understory vegetation complexity contributes to the preservation of spider host–cleptoparasite relationships in oil palm plantations. Understory structural complexity in these simplified agroecosystems therefore helps to support abundant spider populations, a functionally important taxon in agricultural landscapes. In addition, management for more structurally complex agricultural habitats can support more complex trophic interactions in tropical agroecosystems.  相似文献   
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