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211.
Dear Editor, A series of studies had focused on the ecological stability of human microbiome (Lozupone et al.,2012;Faith et al.,2013;Moya and Ferrer,2016).Despite the continuous perturbation and the highly personalized composition within the human microbiome (Human Microbiome Project,2012),healthy adults stably maintain their microbial communities in terms of space and time (Faith et al.,2013;Moya and Ferrer,2016;Oh et al.,2016).This stability is proved to be critical for the well-being of human body (Lozupone et al.,2012).On the contrary,major shifts in microbial community composition are often related to diseases (Lynch and Pedersen,2016).  相似文献   
212.
增温对高寒草甸生态系统碳氮循环耦合关系的影响 陆地生态系统碳吸收受土壤氮素可用性的调节。然而,全球变化背景下的不同生态系统组分的碳氮比及其所反映的碳氮循环耦合关系尚不十分清楚。本文运用数据同化的方法,将一个高寒草甸增温试验的14组数据同化到草地生态系统模型中,从而评估了增温如何影响陆地生态系统的碳氮循环耦合关系。研究结果表明,增温提高了土壤氮素的有效性,降低了土壤活性碳库的碳氮比,导致植物对土壤氮的吸收增加。但是由于植物叶片吸收的碳比吸收的氮增加更多,使得叶片中碳氮比增加,而根部的碳输入增加则低于氮的增加,导致根部的碳氮比减少。同时,增温降低了凋落物碳氮比,可能是在土壤高氮有效性的条件下,凋落物氮的固定得到增强;而且增温加速了凋落物的分解。同时增温还增加了慢速土壤有机质的碳氮比,使得该土壤碳库的碳固存潜力增大。由于大多数模型在不同的环境中通常使用相对固定的碳氮比,本研究所发现的气候变暖条件下碳氮比的差异变化可为模型参数化提供一个有效的参考,有利于模型对未来气候变化背景下生态系统碳氮耦合关系响应的预测。  相似文献   
213.
Wilted black poplar, Populus nigra ‘Italica’ L., leaves are very attractive to a vast number of noctuid moth species. This provides an opportunity for the development of effective trapping methods for the integrated management of pest species, such as Helicoverpa armigera, a major global and economically important insect pest.In the present study, we investigated the (1) nocturnal attraction patterns of H. armigera males and females to wilted P. nigra leaves; (2) effects of P. nigra volatiles on the mate-searching behavior of males through laboratory serial-chamber bioassays and field trapping; and (3) effects of P. nigra volatiles on the ovipositional choice and reproductive performance of females. Females and males, when tested alone, could be attracted by wilted P. nigra leaves, and the time periods of the first two attraction peaks were largely overlapped between sexes. Streams consisting of wilted P. nigra leaves and virgin females were not more attractive than virgin females alone, regardless of the stream sequence in a serial chamber. However, a stream of virgin females passed through wilted P. nigra leaves was more attractive than wilted P. nigra leaves alone. The addition of P. nigra extracts and its major aromatic components to the sex lure of H. armigera did not attract more moths than the sex lure alone. The volatiles from wilted P. nigra leaves were significantly more attractive to ovipositing females than those from cotton, tomato, and corn leaves, but equally attractive to tobacco leaves. Females exposed to volatiles from different leaves (P. nigra, cotton, and tobacco) showed similar fecundities. In summary, the attraction of moths to wilted P. nigra leaves may be attributable to multiple mechanisms, including the adsorption of sex pheromones, ovipostional attraction, and possible feeding attraction.  相似文献   
214.
Moderately to well-preserved radiolarians have been extracted from nine greyish green and purplish-red bedded cherts in the mud-matrix mélange of the eastern Yarlung-Zangbo Suture Zone (YZSZ) at Jinlang Section, Zedong, southern Xizang (Tibet). Forty-two species belonging to 27 genera, including Middle Jurassic characteristic species such as Laxtorum (?) jurassicum Isozaki and Matsuda, Laxtorum (?) hichisoense Isozaki and Matsuda, Stichocapsa japonica Yao, Stichocapsa robusta Matsuoka, Parahsuum (?) magnum Takemura, Sella chrafatensis (El Kadiri), and Unuma typicus Ichikawa and Yao are recognized and three assemblages, Laxtorum (?) jurassicum Assemblage (Aalenian), Quarticella ovalis Assemblage (late Bajocian), and Stichocapsa robusta Assemblage (middle Bathonian) are established in ascending order. These assemblages can be well correlated to the Middle Jurassic Unitary Association (UA) Zones (Baumgartner et al., 1995) in west Tethys and coeval biozones in Japan and provide reliable age information for the Middle Jurassic stratigraphic correlation of the pelagic sediments along the YZSZ.  相似文献   
215.
Emerging evidence suggests that a high-fat diet (HFD) can influence endoplasmic reticulum (ER) stress and gut microbiota. Crataegi Fructus is a traditional Chinese herb widely used in formulas for dyspepsia, with Dashanzha Pill composed of raw Crataegi Fructus (DR) being a representative drug. Processing products of Crataegi Fructus, however, have a stronger pro-digestive effect, and we hypothesized that Dashanzha Pill composed of charred Crataegi Fructus (DC) is more effective. We found that the contents of glucose 1-phosphate and luteolin in DR and DC were substantially different via ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry. DC outperformed DR in improving histopathological changes, increasing gastrin and motilin, and decreasing vasoactive intestinal peptides in rats with HFD induced dyspepsia. Fecal microbiota analysis revealed that DC could restore the disturbed intestinal microbiota composition, including that of Bacteroides, Akkermansia, and Intestinimonas to normal levels. Furthermore, DC significantly reduced the mRNA and protein levels of glucose-regulated protein 78, protein kinase R-like ER kinase, and eukaryotic initiation factor 2α. Taken together, DC outperformed DR in relieving dyspepsia by regulating gut microbiota and alleviating ER stress.  相似文献   
216.
This study aims to construct a robust prognostic model for adult adrenocortical carcinoma (ACC) by large-scale multiomics analysis and real-world data. The RPPA data, gene expression profiles and clinical information of adult ACC patients were obtained from The Cancer Proteome Atlas (TCPA), Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Integrated prognosis-related proteins (IPRPs) model was constructed. Immunohistochemistry was used to validate the prognostic value of the IPRPs model in Fudan University Shanghai Cancer Center (FUSCC) cohort. 76 ACC cases from TCGA and 22 ACC cases from GSE10927 in NCBI’s GEO database with full data for clinical information and gene expression were utilized to validate the effectiveness of the IPRPs model. Higher FASN (P = .039), FIBRONECTIN (P < .001), TFRC (P < .001), TSC1 (P < .001) expression indicated significantly worse overall survival for adult ACC patients. Risk assessment suggested significantly a strong predictive capacity of IPRPs model for poor overall survival (P < .05). IPRPs model showed a little stronger ability for predicting prognosis than Ki-67 protein in FUSCC cohort (P = .003, HR = 3.947; P = .005, HR = 3.787). In external validation of IPRPs model using gene expression data, IPRPs model showed strong ability for predicting prognosis in TCGA cohort (P = .005, HR = 3.061) and it exhibited best ability for predicting prognosis in GSE10927 cohort (P = .0898, HR = 2.318). This research constructed IPRPs model for predicting adult ACC patients’ prognosis using proteomic data, gene expression data and real-world data and this prognostic model showed stronger predictive value than other biomarkers (Ki-67, Beta-catenin, etc) in multi-cohorts.  相似文献   
217.
The use of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) is limited in drug discovery and cardiac disease mechanism studies due to cell immaturity. Micro-scaled grooves can promote the maturation of cardiomyocytes by aligning them in order, but the mechanism of cardiomyocytes alignment has not been studied. From the level of calcium activity, gene expression and cell morphology, we verified that the W20H5 grooves can effectively promote the maturation of cardiomyocytes. The transient receptor potential channels (TRP channels) also play an important role in the maturation and development of cardiomyocytes. These findings support the engineered hPSC-CMs as a powerful model to study cardiac disease mechanism and partly mimic the myocardial morphological development. The important role of the TRP channels in the maturation and development of myocardium is first revealed.  相似文献   
218.
219.
The genetically modified cotton holding Bt proteins, is noxious to bollworms larvae but very little is known about its impact on population of non-target spiders within the field. Studies conducted with the aim to identify spiders along with their abundance, prevalence pattern, preying habit on insect pests in Bt cotton (L280, Cry2Ab4) and commonness of symbiotic bacteria in these spiders. Spiders collections were made via vial tapping/jarring, from May to end of October (2018). In total, 13,342 spiders were recorded during the entire cropping season. Least relative abundance was in May (0.28%), highest in August (30.39%) while ahead decline was observed, reached to 12% in October. The 27 species were verified, least richness was in May (3 species), high in August (19 species), later in the end, reduced to 7 species. High abundance was of Hylyphantes graminicola (68.56%) and Neoscona theisi (19.98%). Existence of H. graminicola and Pardosa astrigera observed during the whole cropping season. Presence of seven guilds among spiders had a diverse nature of hunting insect pests and on number of species existed in the crop, maximum was from direct hunting habit. Composition and community structure of microbiota varied as of spider species. Proteobacteria was the most abundant bacterial phylum and topmost genus was Wolbachia in observed spiders. Five groups of bacteria distinguished across 4 clusters of spiders depending on core community of symbiotic bacterial genera. This effort is an initial step to get knowhow about spiders in Bt cotton, which will facilitate future research studies concerning spiders.  相似文献   
220.
Rhizoremediation is a potential technique for polycyclic aromatic hydrocarbon (PAH) remediation; however, the catabolic pathways of in situ rhizosphere PAH degraders and the main factors driving PAH rhizoremediation remain unclear. To address these issues, stable-isotope-probing coupled with metagenomics and molecular ecological network analyses were first used to investigate the phenanthrene rhizoremediation by three different prairie grasses in this study. All rhizospheres exhibited a significant increase in phenanthrene removal and markedly modified the diversity of phenanthrene degraders by increasing their populations and interactions with other microbes. Of all the active phenanthrene degraders, Marinobacter and Enterobacteriaceae dominated in the bare and switchgrass rhizosphere respectively; Achromobacter was markedly enriched in ryegrass and tall fescue rhizospheres. Metagenomes of 13C-DNA illustrated several complete pathways of phenanthrene degradation for each rhizosphere, which clearly explained their unique rhizoremediation mechanisms. Additionally, propanoate and inositol phosphate of carbohydrates were identified as the dominant factors that drove PAH rhizoremediation by strengthening the ecological networks of soil microbial communities. This was verified by the results of rhizospheric and non-rhizospheric treatments supplemented with these two substances, further confirming their key roles in PAH removal and in situ PAH rhizoremediation. Our study offers novel insights into the mechanisms of in situ rhizoremediation at PAH-contaminated sites.  相似文献   
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