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Antennal sensilla and their nerve innervation in first‐instar nymphs of Porphyrophora sophorae Arch. (Hemiptera: Coccomorpha: Margarodidae) 下载免费PDF全文
ABSTRACT Porphyrophora (Hemiptera: Coccomorpha: Margarodidae) is a genus of soil‐inhabiting scale insects. The antennal sensilla and their innervation in the first‐instar nymphs of Porphyrophora sophorae were studied using light microscopy and scanning and transmission electron microscopy to understand the function of these sensilla and determine the sensillar innervation feature on these small antennae. The results show that the six‐segmented antennae of these nymphs have 20–23 sensilla which can be morphologically classified into seven types, for example, one Böhm's bristle (Bb), one campaniform sensillum (Ca), one Johnston's organ (Jo), 13–16 aporous sensilla trichodea (St), two coeloconic sensilla (Co), one straight multiporous peg (Mp1), and one curvy multiporous peg (Mp2). According to their function, these sensilla can be categorized into three categories: mechanoreceptors, that is, Bb, Ca, Jo, and St; thermo/hygroreceptors, that is, Co only; and chemoreceptors, that is, Mp1 and Mp2. The dendrites that innervate the Mp1, Mp2, and Co sensilla combine to form a large nerve tract (NT1) in the antennal lumen. Because NT1 extends through and out of the antenna, the somata of these neurons are present in the lymph cavity of the insect's head. The dendrites that innervate the mechanoreceptors form another nerve tract (NT2). The somata of these neurons are located inside the scape and pedicel. J. Morphol. 277:1631–1647, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
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Jiaohong Zhao Fudan Gao Jingsong Zhang Teruo Ogawa Weimin Ma 《The Journal of biological chemistry》2014,289(39):26669-26676
Two mutants that grew faster than the wild-type (WT) strain under high light conditions were isolated from Synechocystis sp. strain PCC 6803 transformed with a transposon-bearing library. Both mutants had a tag in ssl1690 encoding NdhO. Deletion of ndhO increased the activity of NADPH dehydrogenase (NDH-1)-dependent cyclic electron transport around photosystem I (NDH-CET), while overexpression decreased the activity. Although deletion and overexpression of ndhO did not have significant effects on the amount of other subunits such as NdhH, NdhI, NdhK, and NdhM in the cells, the amount of these subunits in the medium size NDH-1 (NDH-1M) complex was higher in the ndhO-deletion mutant and much lower in the overexpression strain than in the WT. NdhO strongly interacts with NdhI and NdhK but not with other subunits. NdhI interacts with NdhK and the interaction was blocked by NdhO. The blocking may destabilize the NDH-1M complex and repress the NDH-CET activity. When cells were transferred from growth light to high light, the amounts of NdhI and NdhK increased without significant change in the amount of NdhO, thus decreasing the relative amount of NdhO. This might have decreased the blocking, thereby stabilizing the NDH-1M complex and increasing the NDH-CET activity under high light conditions. 相似文献
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Weimin Zhou Min Zhu Ming Gui Lihua Huang Zhi Long Li Wang Hui Chen Yinghao Yin Xianzhen Jiang Yingbo Dai Yuxin Tang Leye He Kuangbiao Zhong 《PloS one》2014,9(10)
Alterations of mitochondrial DNA (mtDNA) have been associated with the risk of a number of human cancers; however, the relationship between mtDNA copy number in peripheral blood leukocytes (PBLs) and the risk of prostate cancer (PCa) has not been investigated. In a case-control study of 196 PCa patients and 196 age-paired healthy controls in a Chinese Han population, the association between mtDNA copy number in PBLs and PCa risk was evaluated. The relative mtDNA copy number was measured using quantitative real-time PCR; samples from three cases and two controls could not be assayed, leaving 193 cases and 194 controls for analysis. PCa patients had significantly higher mtDNA copy numbers than controls (medians 0.91 and 0.82, respectively; P<0.001). Dichotomized at the median value of mtDNA copy number in the controls, high mtDNA copy number was significantly associated with an increased risk of PCa (adjusted odds ratio = 1.85, 95% confidence interval: 1.21–2.83). A significant dose-response relationship was observed between mtDNA copy number and risk of PCa in quartile analysis (P
trend = 0.011). Clinicopathological analysis showed that high mtDNA copy numbers in PCa patients were significantly associated with high Gleason score and advanced tumor stage, but not serum prostate-specific antigen level (P = 0.002, 0.012 and 0.544, respectively). These findings of the present study indicate that increased mtDNA copy number in PBLs is significantly associated with an increased risk of PCa and may be a reflection of tumor burden. 相似文献
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Enzong Xiao Jinli Cui Weimin Sun Shiming Jiang Mengyan Huang Deguan Kong Qihang Wu Tangfu Xiao Xiaoxu Sun Zengping Ning 《Environmental microbiology》2021,23(4):1959-1971
The assemblage of root-associated microorganisms plays important roles in improving their capability to adapt to environmental stress. Metal(loid) hyperaccumulators exhibit disparate adaptive capability compared to that of non-hyperaccumulators when faced with elevated contents of metal(loid)s. However, knowledge of the assemblage of root microbes of hyperaccumulators and their ecological roles in plant growth is still scarce. The present study used Pteris vittata as a model plant to study the microbial assemblage and its beneficial role in plant growth. We demonstrated that the assemblage of microbes from the associated bulk soil to the root compartment was based on their lifestyles. We used metagenomic analysis and identified that the assembled microbes were primarily involved in root–microbe interactions in P. vittata root. Notably, we identified that the assembled root microbiome played an important role in As requisition, which promoted the fitness and growth of P. vittata. This study provides new insights into the root microbiome and potential valuable knowledge to understand how the root microbiome contributes to the fitness of its host. 相似文献
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Hyojung Cha George Fish Joel Luke Ahmad Alraddadi Hyun Hwi Lee Weimin Zhang Yifan Dong Saurav Limbu Andrew Wadsworth Iuliana P. Maria Laia Francs Hou Lon Sou Tian Du Ji‐Seon Kim Martyn A. McLachlan Iain McCulloch James R. Durrant 《Liver Transplantation》2019,9(27)
Here, it is investigated whether an energetic cascade between mixed and pure regions assists in suppressing recombination losses in non‐fullerene acceptor (NFA)‐based organic solar cells. The impact of polymer‐NFA blend composition upon morphology, energetics, charge carrier recombination kinetics, and photocurrent properties are studied. By changing film composition, morphological structures are varied from consisting of highly intermixed polymer‐NFA phases to consisting of both intermixed and pure phase. Cyclic voltammetry is employed to investigate the impact of blend morphology upon NFA lowest unoccupied molecular orbital (LUMO) level energetics. Transient absorption spectroscopy reveals the importance of an energetic cascade between mixed and pure phases in the electron–hole dynamics in order to well separate spatially localized electron–hole pairs. Raman spectroscopy is used to investigate the origin of energetic shift of NFA LUMO levels. It appears that the increase in NFA electron affinity in pure phases relative to mixed phases is correlated with a transition from a relatively planar backbone structure of NFA in pure, aggregated phases, to a more twisted structure in molecularly mixed phases. The studies focus on addressing whether aggregation‐dependent acceptor LUMO level energetics are a general design requirement for both fullerene and NFAs, and quantifying the magnitude, origin, and impact of such energetic shifts upon device performance. 相似文献
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Jingsi Yi Jiahua Chen Zheng Yang Yang Dai Weimin Li Jiang Cui Francesco Ciucci Ziheng Lu Chunlei Yang 《Liver Transplantation》2019,9(38)
A facile and scalable approach is reported to stabilize the lithium‐metal anode by regulating the Li nucleation and deposition kinetics with laser‐induced graphene (LIG). By processing polyimide (PI) films on copper foils with a laser, a 3D‐hierarchical composite material is constructed, consisting of a highly conductive copper substrate, a pillared array of flexible PI, and most importantly, porous LIG on the walls of the PI pillars. The high number of defects and heteroatoms present in LIG significantly lowers the Li nucleation barrier compared to the copper foil. An overpotential‐free Li nucleation process is identified at current densities lower than 0.2 mA cm?2. Theoretical computations reveal that the defects serve as nucleation centers during the heterogeneous nucleation of lithium. By adopting such composites, ultrastable lithium‐metal anodes are obtained with high Coulombic efficiencies of ≈99%. Full lithium‐metal cells based on LiFePO4 cathodes with a material loading of ≈15 mg cm?2 and a negative/positive ratio of 5/1 could be cycled over 250 times with a capacity loss of less than 10%. The current work highlights the importance of nucleation kinetics on the stability of metallic anodes and demonstrates a practical method toward long lasting Li‐metal batteries. 相似文献
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为探讨杜仲-山茱萸治疗糖尿病的作用机制。研究利用网络药理学的方法,首先通过中药系统药理学数据库筛选出杜仲和山茱萸的活性成分和相关靶点,再利用DisGeNET、DrugBank等数据库筛选出糖尿病的潜在靶点。以STRING数据库对活性靶点构建蛋白互作网络(PPI)分析,采用Cytoscape3.7.0软件绘制其“成分-靶点-通路”的相互作用网络,通过CludterProfiler对靶蛋白进行生物过程、细胞组分及分子功能分析;京都基因与基因组(KEGG)的代谢通路分析。实验结果筛选得到杜仲-山茱萸有效成分30个,其中槲皮素、山奈酚、β-谷甾醇等成分对PTGS2、DPP4、ADRB2、PPARG等相关靶点通过IL-17信号通路、钙信号通路、脂肪细胞脂解的调控等参与氮化合物代谢过程、血液循环、脂肪细胞分化和血压调节等过程。综上,杜仲-山茱萸配伍治疗糖尿病存在多成分和多重药理作用机制,为进一步研究其治疗糖尿病药理实验提供了参考,也为其他中药的相关研究提供借鉴和参考。 相似文献