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91.
Scientific evidence associates indoor environment pollutants with respiratory effects (asthma and allergies), and children constitute one of most sensitive groups. Indoor air quality (IAQ) in schools may indeed be a significant health factor for children, with effects on school attendance and performance. Our aim was to characterize IAQ of classrooms in Maia County (north of Portugal) for which there was no information available. The study was conducted in 21 of the 40 primary schools, selected by stratified random sampling. Depending on the dimension, one or two classrooms were tested at each school. Walkthrough surveys of school grounds, buildings, and individual classrooms were done. Continuous measurements were taken of temperature, relative humidity, airborne respirable particles, total volatile organic compounds, and carbon dioxide, whereas bioaerosols were counted on Plate Count Agar during regular school activities. The indoor arithmetic mean for PM10, CO2, TCOV, and bioaerosol concentrations were 0.14 mg/m3, 999 ppm, 0.41 mg/m3, and 4140 UCF/m3, respectively. The values of PM10 and CO2 were close to their acceptable maximum values, but bioaerosols were much higher. This study supports previous studies conducted in school environments and emphasizes the need for proactive indoor air quality audits in school buildings.  相似文献   
92.
Synthesis and evaluation of new combretastatin analogues with varied modifications on the bridge and the aromatic rings, have shown that the 2-naphthyl moiety is a good surrogate for the 3-hydroxy-4-methoxyphenyl (B-ring) of combretastatin A-4. Other bicyclic systems, such as 6(7)-quinolyl and 5-indolyl, can replace the B-ring, but they produce less potent analogues in the cytotoxicity and tubulin polymerization inhibition assays. Other modifications are detrimentral for the potency of the studied analogues. The 2-naphthyl combretastatin 53 and the related 6-quinolyl combretastatin 106 analogues are the most potent among the derivatives of this type, whereas 92 and 95 are the most potent among the naphthalene derivatives with a heterocycle in the bridge. Previous and new results in this family of combretastatin analogues are discussed.  相似文献   
93.
94.
Olive breeding programmes are focused on selecting for traits as short juvenile period, plant architecture suited for mechanical harvest, or oil characteristics, including fatty acid composition, phenolic, and volatile compounds to suit new markets. Understanding the molecular basis of these characteristics and improving the efficiency of such breeding programmes require the development of genomic information and tools. However, despite its economic relevance, genomic information on olive or closely related species is still scarce. We have applied Sanger and 454 pyrosequencing technologies to generate close to 2 million reads from 12 cDNA libraries obtained from the Picual, Arbequina, and Lechin de Sevilla cultivars and seedlings from a segregating progeny of a Picual × Arbequina cross. The libraries include fruit mesocarp and seeds at three relevant developmental stages, young stems and leaves, active juvenile and adult buds as well as dormant buds, and juvenile and adult roots. The reads were assembled by library or tissue and then assembled together into 81 020 unigenes with an average size of 496 bases. Here, we report their assembly and their functional annotation.  相似文献   
95.
Oxalis pes-caprae, a tristylous flowering plant native to South Africa, is described in the western Mediterranean basin as an asexual—only 5x short-styled morph (5x S-morph) invasive weed losing all mating partners after introduction. The objective of this study was to reassess the patterns of floral morph and cytotype distribution and the sexual reproduction ability in this invaded range. For that, floral morph and cytotype composition were evaluated in 39 populations of O. pes-caprae in a methodical sampling. The reproductive success of natural populations was assessed as fruit and seed production and seed germination for all floral morphs and cytotypes detected. Self- and morph-incompatibility were also studied with controlled hand pollinations. A remarkable diversity in floral morph and cytotype composition was observed. Furthermore, we observed successful sexual reproduction in several localities across the surveyed area. The S-morph is still dominant in this invaded area, and although it was mostly 5x, an additional cytotype (4x) was also recorded. Records of both a mid-styled morph (M-morph) and an area with trimorphic populations of this species are reported here for the first time in the invasive range of the Mediterranean basin. The long-styled morph appears to occur randomly across the surveyed area, while the M-morph is concentrated mainly in Estremadura province (Portugal), where a breakdown in the incompatibility system was observed. These distribution patterns may result from events of sexual reproduction after incompatibility breakdown and/or from multiple introduction events from the native area. The ability to reproduce sexually, undetected so far, may have important impacts in the population dynamics and major consequences for the adaptation and selection potential of O. pes-caprae in this invaded area.  相似文献   
96.
The efficacy of soil treatments of three native entomopathogenic nematodes (Steinernema carpocapsae, S. feltiae and Heterorhabditis bacteriophora) against Tuta absoluta larvae, pupae and adults was determined under laboratory conditions. The effect of three insecticides commonly used against T. absoluta, in the survival, infectivity and reproduction of these nematode strains was also evaluated. When dropped into soil to pupate, soil application of nematodes resulted in a high mortality of larvae: 100, 52.3 and 96.7 % efficacy for S. carpocapsae, S. feltiae and H. bacteriophora respectively. No mortality of pupae was observed and mortality of adults emerging from soil was 79.1 % for S. carpocapsae and 0.5 % for S. feltiae. The insecticides tested had a negligible effect on nematode survival, infectivity and reproduction. No sublethal effects were observed. Infective juveniles that survived to insecticide exposition were able to infect Galleria larvae with no significant differences from the control. The Galleria larvae affected by the three insecticides tested served as suitable hosts for the infection and reproduction of the nematodes. These results suggest that larvae of T. absoluta, falling from leaves following insecticide application, could be suitable hosts for nematodes, thereby increasing their concentration and persistence in the soil.  相似文献   
97.
98.
Plant stomata function in innate immunity against bacterial invasion and abscisic acid (ABA) has been suggested to regulate this process. Using genetic, biochemical, and pharmacological approaches, we demonstrate that (i) the Arabidopsis thaliana nine-specific-lipoxygenase encoding gene, LOX1, which is expressed in guard cells, is required to trigger stomatal closure in response to both bacteria and the pathogen-associated molecular pattern flagellin peptide flg22; (ii) LOX1 participates in stomatal defense; (iii) polyunsaturated fatty acids, the LOX substrates, trigger stomatal closure; (iv) the LOX products, fatty acid hydroperoxides, or reactive electrophile oxylipins induce stomatal closure; and (v) the flg22-mediated stomatal closure is conveyed by both LOX1 and the mitogen-activated protein kinases MPK3 and MPK6 and involves salicylic acid whereas the ABA-induced process depends on the protein kinases OST1, MPK9, or MPK12. Finally, we show that the oxylipin and the ABA pathways converge at the level of the anion channel SLAC1 to regulate stomatal closure. Collectively, our results demonstrate that early biotic signaling in guard cells is an ABA-independent process revealing a novel function of LOX1-dependent stomatal pathway in plant immunity.  相似文献   
99.
Animal studies point to an implication of the endocannabinoid system on executive functions. In humans, several studies have suggested an association between acute or chronic use of exogenous cannabinoids (Δ9-tetrahydrocannabinol) and executive impairments. However, to date, no published reports establish the relationship between endocannabinoids, as biomarkers of the cannabinoid neurotransmission system, and executive functioning in humans. The aim of the present study was to explore the association between circulating levels of plasma endocannabinoids N-arachidonoylethanolamine (AEA) and 2-Arachidonoylglycerol (2-AG) and executive functions (decision making, response inhibition and cognitive flexibility) in healthy subjects. One hundred and fifty seven subjects were included and assessed with the Wisconsin Card Sorting Test; Stroop Color and Word Test; and Iowa Gambling Task. All participants were female, aged between 18 and 60 years and spoke Spanish as their first language. Results showed a negative correlation between 2-AG and cognitive flexibility performance (r = −.37; p<.05). A positive correlation was found between AEA concentrations and both cognitive flexibility (r = .59; p<.05) and decision making performance (r = .23; P<.05). There was no significant correlation between either 2-AG (r = −.17) or AEA (r = −.08) concentrations and inhibition response. These results show, in humans, a relevant modulation of the endocannabinoid system on prefrontal-dependent cognitive functioning. The present study might have significant implications for the underlying executive alterations described in some psychiatric disorders currently associated with endocannabinoids deregulation (namely drug abuse/dependence, depression, obesity and eating disorders). Understanding the neurobiology of their dysexecutive profile might certainly contribute to the development of new treatments and pharmacological approaches.  相似文献   
100.
The role of p110δ PI3K in lymphoid cells has been studied extensively, showing its importance in immune cell differentiation, activation and development. Altered T cell localization in p110δ-deficient mouse spleen suggested a role for p110δ in non-hematopoietic stromal cells, which maintain hematopoietic cell segregation. We tested this hypothesis using p110δWT/WT mouse bone marrow to reconstitute lethally irradiated p110δWT/WT or p110δD910A/D910A (which express catalytically inactive p110δ) recipients, and studied localization, number and percentage of hematopoietic cell subsets in spleen and lymph nodes, in homeostatic conditions and after antigen stimulation. These analyses showed diffuse T cell areas in p110δD910A/D910A and in reconstituted p110δD910A/D910A mice in homeostatic conditions. In these mice, spleen CD4+ and CD8+ T cell numbers did not increase in response to antigen, suggesting that a p110δD910A/D910A stroma defect impedes correct T cell response. FACS analysis of spleen stromal cell populations showed a decrease in the percentage of gp38CD31+ cells in p110δD910A/D910A mice. qRT-PCR studies detected p110δ mRNA expression in p110δWT/WT spleen gp38CD31+ and gp38+CD31+ subsets, which was reduced in p110δD910A/D910A spleen. Lack of p110δ activity in these cell populations correlated with lower LTβR, CCL19 and CCL21 mRNA levels; these molecules participate in T cell localization to specific spleen areas. Our results could explain the lower T cell numbers and more diffuse T cell areas found in p110δD910A/D910A mouse spleen, as well as the lower T cell expansion after antigen stimulation in p110δD910A/D910A compared with p110δWT/WT mice.  相似文献   
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