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1.
In this study, 1-(bromoalkanoyl)-1H-pyrimidine-2,4-diones, (2,4-dioxo-pyrimidin-1-yl)-oxo-alkanoic acids, and bis(2,4-dioxo-3,4-dihydro-2H-pyrimidin-1-yl)-alkanones were successfully prepared via electrophilic substitution of uracil and its derivatives. High yields and pure products were obtained when microwave and ultrasound methodologies were used for undertaking the reactions. Importantly, the use of 4-dimethylaminopyridine in the present investigation gave rise to higher conversions of the starting material and afforded facile access to regioselective N-1 products.  相似文献   
2.
The possibility of obtaining immobilized horseradish peroxidase (HRP) materials with K'(m) values close to that of the native enzyme, but with good thermal stability, was investigated. The photochemical reaction was used as the immobilization methodology. Temperature and catalyst concentration were found to be the main parameters able to control the immobilization reaction mechanism more than type of functional monomer, polymer-matrix, and enzyme-polymer ratios. By carrying out the immobilization reaction at 35 degrees C and using either bisacryloylpiperazine (BAP) or hexhydro-1,3,5-triacryloyl-s-triazine (HTsT) as the functional monomer, materials with a good thermal stabilization (the retained activity after 240 min at 60 degrees C was between 65-25%) as well as kinetic constants (0.6-0.8 x 10(-4)M) similar to that of the free enzyme (0.57 x 10(-4)M) were obtained. Since low K'(m) values were obtained also using a high polymer content (pBAP copolymers, 25%; pHTsT copolymers, 30%) and neither limitation to substrate diffusion nor a reduction of the enzyme mobility was found, the enzyme should be linked to the matrix during the last steps of monomer polymerization, and it should have an external disposition with respect to the support.  相似文献   
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4.
After experimental treatment of rats with clofibrate or ciprofibrate, two peroxisomes proliferators with hypolipidemic activity, RNAs were prepared from liver, kidney, heart and brain; hybridization was done with DNA probes for c-myc and c-Ha-ras oncogenes and for cyanide insensitive Acyl CoA oxidase, a peroxisomal protein. c-myc mRNA is highly abundant in liver and at a lower extent in kidney, especially after treatment with ciprofibrate; clofibrate also allows a c-myc mRNA increase, but at a lower extent. c-Ha-ras, which is already expressed in all tested tissues from control animals, is stimulated by clofibrate and ciprofibrate treatments. Comparatively these compounds stimulate the cyanide insensitive Acyl CoA oxidase expression as well as they increase the somatic index of liver and kidney. From these experiments we suggest that hepatocarcinogenesis triggered by some hypolipidemic agents could be mediated by proto-oncogene mRNA level increase.  相似文献   
5.
Lipid metabolism is critical to coordinate organ development and physiology in response to tissue-autonomous signals and environmental cues. Changes to the availability and signaling of lipid mediators can limit competitiveness, adaptation to environmental stressors, and augment pathological processes. Two classes of lipids, the N-acyl amides and the 2-acyl glycerols, have emerged as important signaling molecules in a wide range of species with important signaling properties, though most of what is known about their cellular functions is from mammalian models. Therefore, expanding available knowledge on the repertoire of these lipids in invertebrates will provide additional avenues of research aimed at elucidating biosynthetic, metabolic, and signaling properties of these molecules. Drosophila melanogaster is a commonly used organism to study intercellular communication, including the functions of bioactive lipids. However, limited information is available on the molecular identity of lipids with putative biological activities in Drosophila. Here, we used a targeted lipidomics approach to identify putative signaling lipids in third instar Drosophila larvae, possessing particularly large lipid mass in their fat body. We identified 2-linoleoyl glycerol, 2-oleoyl glycerol, and 45 N-acyl amides in larval tissues, and validated our findings by the comparative analysis of Oregon-RS, Canton-S and w1118 strains. Data here suggest that Drosophila represent another model system to use for the study of 2-acyl glycerol and N-acyl amide signaling.  相似文献   
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BackgroundThe negative effects of perinatal depression on the mother and child start early and persist throughout the lifecourse (Lancet 369(9556):145–57, 2007; Am J Psychiatry 159(1):43-7, 2002; Arch Dis Child 77(2):99–101, 1997; J Pak Med Assoc 60(4):329; J Psychosoma Res 49(3):207–16, 2000; Clin Child Fam Psychol Rev 14(1):1–27, 2011). Given that 10–35 % of children worldwide are exposed to perinatal depression in their first year of life (Int Rev Psychiatry 8(1):37–54, 1996), mitigating this intergenerational risk is a global public health priority (Perspect Public Health 129(5):221–7, 2009; Trop Med Int Health 13(4):579–83, 2008; Br Med Bull 101(1):57–79, 2012). However, it is not clear whether intervention with depressed women can have long-term benefits for the mother and/or her child. We describe a study of the effectiveness of a peer-delivered depression intervention delivered through 36 postnatal months, the Thinking Healthy Program Peer-delivered PLUS (THPP+) for women and their children in rural Pakistan.Methods/designThe THPP+ study aims are: (1) to evaluate the effects of an extended 36-month perinatal depression intervention on maternal and index child outcomes using a cluster randomized controlled trial (c-RCT) and (2) to determine whether outcomes among index children of perinatally depressed women in the intervention arm converge with those of index children born to perinatally nondepressed women. The trial is designed to recruit 560 pregnant women who screened positive for perinatal depression (PHQ-9 score ≥10) from 40 village clusters, of which 20 receive the THPP+ intervention. An additional reference group consists of 560 perinatally nondepressed women from the same 40 clusters as the THPP+ trial. The women in the nondepressed group are not targeted to receive the THPP+ intervention; but, by recruiting pregnant women from both intervention and control clusters, we are able to evaluate any carryover effects of the THPP+ intervention on the women and their children. Perinatally depressed women in the THPP+ intervention arm receive bimonthly group-based sessions. Primary outcomes are 3-year maternal depression and 3-year child development indicators. Analyses are intention-to-treat and account for the clustered design.DiscussionThis trial, together with the reference group, has the potential to further our understanding of the early developmental lifecourse of children of both perinatally depressed and perinatally nondepressed women in rural Pakistan and to determine whether intervening with women’s depression in the perinatal period can mitigate the negative effects of maternal depression on 36-month child development.

Trial registration

THPP-P ClinicalTrials.gov Identifier: NCT02111915 (registered on 9 April 2014).THPP+ ClinicalTrials.gov Identifier: NCT02658994 (registered on 21 January 2016).Sponsor: Human Development Research Foundation (HDRF).

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1530-y) contains supplementary material, which is available to authorized users.  相似文献   
8.

This study evaluated the effect of application of the semisynthetic triterpenes 3β-acetoxy-norlup-20-one (F4) and 3-chloro-4α,14α-dimethyl-5α-cholest-8-ene (F6) triterpene derivatives from Euphorbia officinarum on the growth of tomato seedlings under normal conditions and when challenged with the pathogens Verticillium dahliae and Agrobacterium tumefaciens. Foliar spray of F4 and F6 significantly improved growth rate, fresh weight, dry weight, and leaf area. In addition, they enhanced several physiological parameters including photosynthetic pigments, proline content, and nitrate reductase activity. Moreover, they induced H2O2 accumulation and increased the activity of several antioxidant enzymes such as catalase, ascorbate peroxidase, and guaiacol peroxidase. They also enhanced disease resistance against V. dahliae and A. tumefaciens. These results suggest that the two semisynthetic triterpenes represent new plant growth regulators and inducers of plant disease resistance.

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9.
A field trial was established in Errachidia, southern Morocco, to investigate the interaction between wheat residue management and mineral 15N-labelled ammonium sulphate, under different irrigation treatments, applied to wheat (Triticum durum var. Karim). In treatments I1, I2, I3 and I4, plots were irrigated every 10, 15, 21 and 30 days. Each plot contained three sub-plots that received three fertilization treatments: T1 received 42 kg N ha-1 of ammonium sulphate before seedling, 42 kg N ha-1 of ammonium sulphate labelled with 9.764 at % 15N excess at tillering and 84 N kg ha-1 of ammonium sulphate at flowering; T2 received 42 kg N ha-1 of ammonium sulphate labelled with 9.764 at % 15N excess at seedling, 42 kg N ha-1 at tillering and 42 kg N ha-1 at flowering; T3 received 4800 kg ha-1 of wheat residue labelled with 1.504 at % 15N excess and 42 kg N ha-1 of ammonium sulphate before seedling and 42 kg N ha-1 of ammonium sulphate at flowering. Nitrogen fertilization with 168 kg N ha-1 did no significantly increase grain and straw yields in comparison to the 126 kg N ha-1 application. The combination of the organic input and supplementary application of mineral fertilizer N has been found as a more attractive management option. For all irrigation treatments, the % recovery of N in the whole plant was higher in plants that received 15N at tillering (63%, 49% respectively for irrigation intervals between 10 and 30 d) than in plants that received 15N just after seeding (28% for irrigation each 10- and 30-d intervals). For the irrigation treatment each 10 and 15 days, the 15N was mainly recovered by the grain for all fertilization treatments, whereas for irrigation treatment each 30 days, the grain and straw recovered nearly equal amounts of fertilizer. For grain and straw of wheat, nitrogen in the plant derived from the fertilizer was low, while most of the N was derived from the soil for all irrigation and fertilization treatments. The % nitrogen in the plant derived from the fertilizer values showed no significant difference between the different plant parts. The results suggested a dominant influence of moisture availability on the fertilizer N uptake by wheat. Under dry conditions the losses of N can be allotted to denitrification and volatilisation.  相似文献   
10.
Streptococcus mitis has emerged as one of the leading causes of bacterial endocarditis and is related to Streptococcus pneumoniae. Antibiotic resistance has also increased among strains of S. mitis and S. pneumoniae. Phages are being reinvestigated as alternatives to antibiotics for managing infections. In this study, the two virulent phages Cp-1 (Podoviridae) and Dp-1 (Siphoviridae), previously isolated from S. pneumoniae, were found to also infect S. mitis. Microbiological assays showed that both pneumophages could not only replicate in S. mitis but also produced more visible plaques on this host. However, the burst size and phage adsorption data were lower in S. mitis as compared to S. pneumoniae. A comparison of the genomes of each phage grown on both hosts produced identical nucleotide sequences, confirming that the same phages infect both bacterial species. We also discovered that the genomic sequence of podophage Cp-1 of the Félix d’Hérelle collection is different than the previously reported sequence and thus renamed SOCP.  相似文献   
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