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Ubiquitous Water-Soluble Molecules in Aquatic Plant Exudates Determine Specific Insect Attraction 下载免费PDF全文
Julien Srandour Stphane Reynaud John Willison Joëlle Patouraux Thierry Gaude Patrick Ravanel Guy Lemprire Muriel Raveton 《PLoS Clinical Trials》2008,3(10)
Plants produce semio-chemicals that directly influence insect attraction and/or repulsion. Generally, this attraction is closely associated with herbivory and has been studied mainly under atmospheric conditions. On the other hand, the relationship between aquatic plants and insects has been little studied. To determine whether the roots of aquatic macrophytes release attractive chemical mixtures into the water, we studied the behaviour of mosquito larvae using olfactory experiments with root exudates. After testing the attraction on Culex and Aedes mosquito larvae, we chose to work with Coquillettidia species, which have a complex behaviour in nature and need to be attached to plant roots in order to obtain oxygen. This relationship is non-destructive and can be described as commensal behaviour. Commonly found compounds seemed to be involved in insect attraction since root exudates from different plants were all attractive. Moreover, chemical analysis allowed us to identify a certain number of commonly found, highly water-soluble, low-molecular-weight compounds, several of which (glycerol, uracil, thymine, uridine, thymidine) were able to induce attraction when tested individually but at concentrations substantially higher than those found in nature. However, our principal findings demonstrated that these compounds appeared to act synergistically, since a mixture of these five compounds attracted larvae at natural concentrations (0.7 nM glycerol, <0.5 nM uracil, 0.6 nM thymine, 2.8 nM uridine, 86 nM thymidine), much lower than those found for each compound tested individually. These results provide strong evidence that a mixture of polyols (glycerol), pyrimidines (uracil, thymine), and nucleosides (uridine, thymidine) functions as an efficient attractive signal in nature for Coquillettidia larvae. We therefore show for the first time, that such commonly found compounds may play an important role in plant-insect relationships in aquatic eco-systems. 相似文献
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P‐R Burgel I Fajac D Hubert D Grenet N Stremler M Roussey D Siret J Languepin L Mely A Fanton A Labbé P Domblides P Vic M Dagorne M Reynaud‐Gaubert F Counil F Varaigne T Bienvenu G Bellis D Dusser 《Clinical genetics》2010,77(4):355-364
Burgel P‐R, Fajac I, Hubert D, Grenet D, Stremler N, Roussey M, Siret D, Languepin J, Mely L, Fanton A, Labbé A, Domblides P, Vic P, Dagorne M, Reynaud‐Gaubert M, Counil F, Varaigne F, Bienvenu T, Bellis G, Dusser D. Non‐classic cystic fibrosis associated with D1152H CFTR mutation. Background: Limited knowledge exists on phenotypes associated with the D1152H cystic fibrosis transmembrane conductance regulator (CFTR) mutation. Methods: Subjects with a D1152H allele in trans with another CFTR mutation were identified using the French Cystic Fibrosis Registry. Phenotypic characteristics were compared with those of pancreatic insufficient (PI) and pancreatic sufficient (PS) cystic fibrosis (CF) subjects in the Registry (CF cohort). Results: Forty‐two subjects with D1152H alleles were identified. Features leading to diagnosis included chronic sinopulmonary disease (n = 25), congenital absence of the vas deferens (n = 11), systematic neonatal screening (n = 4), and genetic counseling (n = 2). Median age at diagnosis was 33 [interquartile range (IQR, 24–41)] years in D1152H subjects. Median sweat chloride concentrations were 43.5 (39–63) mmol/l in D1152H subjects and were markedly lower than in PI and PS CF subjects (p < 0.05). Bronchiectasis was present in 67% of D1152H subjects, but Pseudomonas aeruginosa colonization and pancreatic insufficiency were present in <30% of subjects. Estimated rates of decline in forced expiratory volume in 1 s (FEV1) were lower in D1152H subjects vs PI CF subjects (p < 0.05). None of the D1152H subjects identified since 1999 had died or required lung transplantation. Conclusions: When present in trans with a CF‐causing mutation, D1152H causes significant pulmonary disease, but all subjects had prolonged survival. 相似文献
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CA Tan D. del Gaudio M.A. Dempsey K. Arndt S. Botes A. Reeder S. Das 《Clinical genetics》2014,85(4):353-358
Primary Autosomal Recessive Microcephaly (MCPH) is characterized by congenital microcephaly usually without additional clinical findings. The most common gene implicated in MCPH is ASPM and a large percentage of mutations described have been homozygous and in consanguineous families primarily of East Asian and Middle Eastern origin. ASPM sequencing was performed on 400 patients between the years 2009 and 2012. Seventy of the patient samples were also analyzed for copy number changes in the ASPM gene. Forty protein truncating mutations, including 29 novel mutations, were identified in 39 patients with MCPH. Approximately one third of patients were compound heterozygotes, indicative of non‐consanguinity in these patients. In addition, 46 non‐synonymous variants were identified and interpreted as variants of uncertain significance. No deletion/duplication in ASPM was identified in the patients analyzed. A wide ethnic distribution was observed, including the first reported patients with ASPM‐related MCPH of Hispanic descent. Clinical information was collected for 26 of the ASPM‐positive patients and 41 of the ASPM‐negative patients. As more individuals are identified with MCPH, we anticipate that we will continue to identify ASPM mutation‐positive patients from all ethnic origins supporting the occurrence of this genetic condition beyond that of consanguineous families of certain ethnic populations. 相似文献
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目的 白细胞介素 1 3(IL 1 3)是新近发现的一种抗炎性细胞因子 ,其在肾小球肾炎中的作用尚不清楚 ,该研究探讨脂多糖 (LPS)对体外培养的人肾小球系膜细胞 (HMC)表达IL 1 3作用以及IL 1 3对HMC促炎性细胞因子、趋化因子和促纤维化因子基因表达的影响。方法 体外培养HMC ,加入不同浓度的LPS和 (或 )IL 1 3后 ,用逆转录 -聚合酶链反应和ELISA检测HMCIL 1 3mRNA表达和细胞培养上清液中IL 1 3蛋白含量 ;应用核酸酶保护法检测HMC肿瘤坏死因子 α(TNF α)、白介素 - 1α(IL 1α)、白介素 - 1 β(IL 1 β)、单核细胞趋化蛋白 1(MCP 1 )、白介素 8(IL 8)、转化生长因子 - β1 (TGF β1 )mRNA的表达。 结果 未予LPS刺激的HMC不表达IL 1 3mRNA和蛋白 ;LPS呈剂量依赖性和时间依赖性诱导HMC表达IL 1 3mRNA和分泌IL 1 3蛋白。HMC受LPS刺激后 1 2h即可表达IL 1 3mRNA ,4 8h达高峰 ,72h仍维持在较高的水平。HMC受LPS刺激后 2 4h ,其培养上清液中检测到IL 1 3蛋白 ,4 8h和 72h进一步增加。外源性IL 1 3呈剂量依赖性地抑制LPS诱导的系膜细胞TNF α ,IL 1α ,IL 1 β ,MCP 1 ,IL 8,TGF β1mRNA的表达。应用抗IL 1 3抗体中和内源性IL 1 3后 ,上述炎症因子表达增强。结论 IL 1 3是HMC自分泌因子。IL 1 3可抑制LPS诱导 相似文献
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目的 探讨病毒性心肌炎患儿心率变异性(HRV)与心率减速力(DC)各项指标变化的临床意义.方法 对56例病毒性心肌炎患儿与58例正常对照儿童进行24h动态心电图检查,应用美国DMS公司的动态心电分析系统软件,对HRV及DC各项参数进行分析对比;并分析DC与其他各项指标之间的相关性.结果 与正常对照儿童比较,病毒性心肌炎患儿时域分析的各项参数包括正常窦性RR间期的标准差(SDNN)、每5 min时段内平均正常窦性RR间期的标准差(SDANN)、全程RR间期差的均方根(RMSSD)及频域分析的低频功率(LF)的差异均无统计学意义(P>0.05),而高频功率(HF)显著减低,差异有统计学意义(P<0.05),且DC显著减低,差异有统计学意义(P<0.01).相关性分析中,DC与SDNN、LF、HF均成正相关,其中与HF的相关性最强(r=0.51,P<0.01).结论病毒性心肌炎患儿存在迷走神经功能受损,心率变异性中的HF与DC反映迷走神经功能的指标均显著降低,且两者具有很大相关性. 相似文献
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