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21.
Vaccination represents one of the greatest public health triumphs; in part due to the effect of adjuvants that have been included in vaccine preparations to boost the immune responses through different mechanisms. Although a variety of novel adjuvants have been under development, only a limited number have been approved by regulatory authorities for human vaccines. This report reflects the conclusions of a group of scientists from academia, regulatory agencies and industry who attended a conference on the current state of the art in the adjuvant field. Held at the U.S. Pharmacopeial Convention (USP) in Rockville, Maryland, USA, from 18 to 19 April 2013 and organized by the International Association for Biologicals (IABS), the conference focused particularly on the future development of effective adjuvants and adjuvanted vaccines and on overcoming major hurdles, such as safety and immunogenicity assessment, as well as regulatory scrutiny. More information on the conference output can be found on the IABS website, http://www.iabs.org/.  相似文献   
22.
Adenosine plays an important role during inflammation, particularly through modulation of monocyte function. The objective of the present study was to evaluate the effect of synthetic adenosine analogs on cytokine production by porcine monocytes. The LPS-stimulated cytokine production was measured by flow cytometry and quantitative real-time PCR. Adenosine receptor expression was measured by quantitative real-time PCR. The present study demonstrates that adenosine analog N-ethylcarboxyamidoadenosine (NECA) down-regulates TNF-α production and up-regulates IL-8 production by LPS-stimulated porcine monocytes. The effect was more pronounced in CD163? subset of monocytes compared to the CD163+ subset. Although both monocyte subsets express mRNA for A1, A2A, A2B and A3 adenosine receptors, the treatment of monocytes with various adenosine receptor agonists and antagonists proved that the effect of adenosine is mediated preferentially via A2A adenosine receptor. Moreover, the study suggests that the effect of NECA on porcine monocytes alters the levels of the cytokines which could play a role in the differentiation of naive T cells into Th17 cells. The results suggest that adenosine plays an important role in modulation of cytokine production by porcine monocytes.  相似文献   
23.
This study used malondialdehyde (MDA) determination by HPLC and enzymatic assays for total serum peroxides and antioxidant capacity to evaluate oxidative stress in 47 healthy full-term small-for-gestational age (SGA) newborns vs 67 appropriate-for-gestational age (AGA) newborns. Blood samples were collected at delivery from umbilical cord artery and vein and from peripheral blood of the babies on the third day after birth. Blood samples of mothers were also collected and compared with blood of 29 normal non-pregnant women (NPW). Serum peroxide values were significantly higher in both groups of mothers than in NPW, decreasing towards the third day in AGA mothers, while persisting in SGA mothers. Antioxidant capacity of sera of both groups of mothers was lower than NPW. Both SGA mothers and babies had increased MDA at delivery, unlike AGA counterparts. MDA levels in umbilical vein were higher than in umbilical arteries, while immunohistochemistry revealed abundant presence of 4-hydroxynonenal (HNE)-protein adducts only in stroma of the SGA placenta. These results show that both mothers and babies are exposed to oxidative stress during and after delivery, which is more pronounced and persistent in the perinatal period of the SGA group, while lipid peroxidation in placenta could play a role in SGA pathophysiology.  相似文献   
24.
Abstract

Acyclic nucleotide analogs derived from antiviral 9-(2-phosphonylmethoxyethyl)adenine by modification at the side chain or by alternation of the heterocyclic base were synthesized and investigated for their antiviral activity.  相似文献   
25.

Background

As for other major crops, achieving a complete wheat genome sequence is essential for the application of genomics to breeding new and improved varieties. To overcome the complexities of the large, highly repetitive and hexaploid wheat genome, the International Wheat Genome Sequencing Consortium established a chromosome-based strategy that was validated by the construction of the physical map of chromosome 3B. Here, we present improved strategies for the construction of highly integrated and ordered wheat physical maps, using chromosome 1BL as a template, and illustrate their potential for evolutionary studies and map-based cloning.

Results

Using a combination of novel high throughput marker assays and an assembly program, we developed a high quality physical map representing 93% of wheat chromosome 1BL, anchored and ordered with 5,489 markers including 1,161 genes. Analysis of the gene space organization and evolution revealed that gene distribution and conservation along the chromosome results from the superimposition of the ancestral grass and recent wheat evolutionary patterns, leading to a peak of synteny in the central part of the chromosome arm and an increased density of non-collinear genes towards the telomere. With a density of about 11 markers per Mb, the 1BL physical map provides 916 markers, including 193 genes, for fine mapping the 40 QTLs mapped on this chromosome.

Conclusions

Here, we demonstrate that high marker density physical maps can be developed in complex genomes such as wheat to accelerate map-based cloning, gain new insights into genome evolution, and provide a foundation for reference sequencing.  相似文献   
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Recent research suggests that domesticated species – due to artificial selection by humans for specific, preferred behavioral traits – are better than wild animals at responding to visual cues given by humans about the location of hidden food. \Although this seems to be supported by studies on a range of domesticated (including dogs, goats and horses) and wild (including wolves and chimpanzees) animals, there is also evidence that exposure to humans positively influences the ability of both wild and domesticated animals to follow these same cues. Here, we test the performance of Asian elephants (Elephas maximus) on an object choice task that provides them with visual-only cues given by humans about the location of hidden food. Captive elephants are interesting candidates for investigating how both domestication and human exposure may impact cue-following as they represent a non-domesticated species with almost constant human interaction. As a group, the elephants (n = 7) in our study were unable to follow pointing, body orientation or a combination of both as honest signals of food location. They were, however, able to follow vocal commands with which they were already familiar in a novel context, suggesting the elephants are able to follow cues if they are sufficiently salient. Although the elephants’ inability to follow the visual cues provides partial support for the domestication hypothesis, an alternative explanation is that elephants may rely more heavily on other sensory modalities, specifically olfaction and audition. Further research will be needed to rule out this alternative explanation.  相似文献   
29.
Mitochondrial respiratory chain is organised into supramolecular structures that can be preserved in mild detergent solubilisates and resolved by native electrophoretic systems. Supercomplexes of respiratory complexes I, III and IV as well as multimeric forms of ATP synthase are well established. However, the involvement of complex II, linking respiratory chain with tricarboxylic acid cycle, in mitochondrial supercomplexes is questionable. Here we show that digitonin-solubilised complex II quantitatively forms high molecular weight structures (CIIhmw) that can be resolved by clear native electrophoresis. CIIhmw structures are enzymatically active and differ in electrophoretic mobility between tissues (500 – over 1000 kDa) and cultured cells (400–670 kDa). While their formation is unaffected by isolated defects in other respiratory chain complexes, they are destabilised in mtDNA-depleted, rho0 cells. Molecular interactions responsible for the assembly of CIIhmw are rather weak with the complexes being more stable in tissues than in cultured cells. While electrophoretic studies and immunoprecipitation experiments of CIIhmw do not indicate specific interactions with the respiratory chain complexes I, III or IV or enzymes of the tricarboxylic acid cycle, they point out to a specific interaction between CII and ATP synthase.  相似文献   
30.
Diploid Aegilops umbellulata and Ae. comosa and their natural allotetraploid hybrids Ae. biuncialis and Ae. geniculata are important wild gene sources for wheat. With the aim of assisting in alien gene transfer, this study provides gene-based conserved orthologous set (COS) markers for the U and M genome chromosomes. Out of the 140 markers tested on a series of wheat-Aegilops chromosome introgression lines and flow-sorted subgenomic chromosome fractions, 100 were assigned to Aegilops chromosomes and six and seven duplications were identified in the U and M genomes, respectively. The marker-specific EST sequences were BLAST-ed to Brachypodium and rice genomic sequences to investigate macrosyntenic relationships between the U and M genomes of Aegilops, wheat and the model species. Five syntenic regions of Brachypodium identified genome rearrangements differentiating the U genome from the M genome and from the D genome of wheat. All of them seem to have evolved at the diploid level and to have been modified differentially in the polyploid species Ae. biuncialis and Ae. geniculata. A certain level of wheat–Aegilops homology was detected for group 1, 2, 3 and 5 chromosomes, while a clearly rearranged structure was showed for the group 4, 6 and 7 Aegilops chromosomes relative to wheat. The conserved orthologous set markers assigned to Aegilops chromosomes promise to accelerate gene introgression by facilitating the identification of alien chromatin. The syntenic relationships between the Aegilops species, wheat and model species will facilitate the targeted development of new markers specific for U and M genomic regions and will contribute to the understanding of molecular processes related to allopolyploidization.  相似文献   
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