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181.
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为了更好地分离珠江口未/难培养的浮游细菌,本研究以珠江河口三个样点的水体为研究对象,同时采用了纯培养和免培养的方法,对不同培养基的分离效果进行了探索。在纯培养实验中,本研究选择了7种不同的分离培养基,共分离获得153株菌;同时,将扩增子分析结果作为分离效果的参考,所有环境样品中共包含3 553个操作分类单元(operational taxonomic units,OTUs)。对三个样点微生物类群的多样性进行比较,纯培养结果显示珠江口下游珠海样点多样性最高,其次为中大和虎门样点;免培养则显示虎门样点多样性最高;对比7种不同的分离培养基,Z7(R2A)培养基的分离效果最好,分离菌株数和分离类群的α多样性最高,Z1(改良ISP 2)次之;主坐标分析结合韦恩图的结果表明相比其余的培养基,Z1和Z7培养基分离获得的菌群兼具普遍性和特异性,进一步证明了这两种培养基的分离效果较佳;冗余分析结果表明K2HPO4、酵母粉、可溶性淀粉、MgSO4·7H2O、麦芽膏和葡萄糖与特定类群的分离有相关关系,其中K2HPO4的影响最为显著(P<0.05)。本文通过7种不同培养基对河口微生物分离效果的探究,有助于我们在研究未知微生物的营养特性时,选择成分和组成更合理的培养基来提升河口微生物纯培养的分离效率。 相似文献
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Arbuscular mycorrhizal fungi (AMF) can improve plant tolerance to several abiotic stresses, including heavy
metals, drought or salinity exposure. However, the role of AMF in alleviation of soil cadmium (Cd)-induced toxicity to plants is still largely unknown. In this study, Cd speciation in soil and subcellular distribution of Cd were
used to characterize the roles of application AM fungi in the alleviation of Cd toxicity in alfalfa plants. Our results
showed that the addition of Glomus mosseae in Cd contaminated soil (10 mg/Kg) significantly increased soil pH,
cation exchange capacity (CEC) and organic matter in rhizosphere soil with Medicago truncatula L., and then
account for significantly decreased contents of exchangeable and carbonate-bounded Cd speciation in rhizosphere
soil, indicating alleviation of plant toxicity by reduction of bioavailable fractions of Cd. Although there is no significant difference found in Cd accumulation by roots and shoots respectively between Cd and AM-Cd treatments, more portion of Cd was recorded compartmentalization in cell wall fraction of both root and shoot in
treatment of Cd with AM application, indicating alleviation of Cd toxicity to plant cell. Herein, application of
AM fungi in Cd treatments performed to inhibit the appearance of Cd toxicity symptoms, including the improvement of leaf electrolyte leakage, root elongation, seedling growth and biomass. This information provides a clearer
understanding of detoxification strategy of AM fungi on Cd behavior with development and stabilization of soil
structure and subcellular distribution of plant. 相似文献
185.
Ligustrazine inhibits the proliferation and migration of ovarian cancer cells via regulating miR-211
Ovarian cancer (OC) is a commonly diagnosed female cancer. Ligustrazine (LSZ), a natural compound, has been reported to exert anti-cancer activity, although the mechanisms underlying the anti-cancer effects are not clear. The present study investigated the impact of LSZ on cell proliferation and migration by regulating microRNA-211 (miR-211) expression using the human ovarian cancer SK-OV-3 and OVCAR-3 cell lines. OC cells were treated with 0, 0.5, 1, and 2 mM LSZ, and quantitative real-time PCR was utilized to measure miR-211 levels in SK-OV-3 and OVCAR-3 cells with different treatment. Moreover, to further confirm the roles of miR-211 in LSZ induced anti-tumor effects, miR-211 expression was inhibited by transfection of miR-211 inhibitors in SK-OV-3 cells. Cell proliferation of transfected cells was evaluated using the CCK-8 and colony formation assay. The scratch assay was employed to assess cell migration and transwell assay was performed for evaluating the cell invasion. Protein levels of epithelial–mesenchymal transition (EMT) markers were determined by Western blotting. We found that LSZ inhibited the viability, proliferation, migration and invasion ability of SK-OV-3 and OVCAR-3 cells in a dose-dependent manner; moreover, LSZ could significantly increase the expression of miR-211 in both SK-OV-3 and OVCAR-3, and knockdown of miR-211 in SK-OV-3 cells partially abrogated the anti-tumor behavior of LSZ by promoting the viability, proliferation, migration, invasion and EMT of SK-OV-3 cells. Thus, we found that LSZ can inhibit the proliferation and migration of OC cells via regulating miR-211. Our study suggests that LSZ might be a potential and effective treatment for OC. 相似文献
186.
Yuhua Chen Hao Zhou Zhendong Wang Zhanghao Huang Jinjie Wang Miaosen Zheng Xuejun Ni Lei Liu 《Bioscience reports》2021,41(5)
Background: Esophageal cancer (ESCA) is one of the most commonly diagnosed cancers in the world. Tumor immune microenvironment is closely related to tumor prognosis. The present study aimed at analyzing the competing endogenous RNA (ceRNA) network and tumor-infiltrating immune cells in ESCA.Methods: The expression profiles of mRNAs, lncRNAs, and miRNAs were downloaded from the Cancer Genome Atlas database. A ceRNA network was established based on the differentially expressed RNAs by Cytoscape. CIBERSORT was applied to estimate the proportion of immune cells in ESCA. Prognosis-associated genes and immune cells were applied to establish prognostic models basing on Lasso and multivariate Cox analyses. The survival curves were constructed with Kaplan–Meier method. The predictive efficacy of the prognostic models was evaluated by the receiver operating characteristic (ROC) curves.Results: The differentially expressed mRNAs, lncRNAs, and miRNAs were identified. We constructed the ceRNA network including 23 lncRNAs, 19 miRNAs, and 147 mRNAs. Five key molecules (HMGB3, HOXC8, HSPA1B, KLHL15, and RUNX3) were identified from the ceRNA network and five significant immune cells (plasma cells, T cells follicular helper, monocytes, dendritic cells activated, and neutrophils) were selected via CIBERSORT. The ROC curves based on key genes and significant immune cells all showed good sensitivity (AUC of 3-year survival: 0.739, AUC of 5-year survival: 0.899, AUC of 3-year survival: 0.824, AUC of 5-year survival: 0.876). There was certain correlation between five immune cells and five key molecules.Conclusion: The present study provides an effective bioinformatics basis for exploring the potential biomarkers of ESCA and predicting its prognosis. 相似文献
187.
Lei Lei Yang Luomiao Cui Bowen Liu HuaLong Wang Jingguo Zheng Hongliang Xin Wei Zou Detang 《Plant Growth Regulation》2021,95(1):97-110
Plant Growth Regulation - β-ketoacyl-CoA synthase is a key enzyme in the biosynthesis of over-long-chain fattty acids; thus, it plays a crucial role in plant resistance to stress. Herein, 33... 相似文献
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Length-to-weight and length-to-length ratios were estimated for six cavefishes including Yunnanilus longibarbatus, Yunnanilus bailianensis, Yunnanilus jinxiensis, Oreonectes polystigmus, Paranemachilus pingguoensis, and Paranemachilus genilepis from the upper reaches of the Pearl River, Guangxi Province, China (between 106.26E, 23.14N and 111.42E, 24.85N). The fish were captured between May and October in 2018 and 2019 using trap nets (mesh size 7 mm) set in front of selected caves at 6:30–7:30 p.m. and were hauled out at 6:30–7:30 a.m. the next day. After removal, the fish were measured and weighed immediately to the nearest 0.1 cm and 0.1 g, respectively. The regression parameter r2 was between .95 and .98. The total length-to-standard length ratios were also calculated with r2 ≥ .98. This study should provide a useful reference for biological studies and biodiversity conservation of cavefish. 相似文献