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111.
Graziella Hanna Pereira Aline Queiroz Santos Miriam Park Patricia Rady Muller Soraia Padua Raquel Ferrari Marchesi Vera Lucia Aldred 《Mycopathologia》2010,170(4):259-261
Paracoccidioides brasiliensis rarely shows bone marrow involvement and its response to treatment with itraconazole in children needs further assessment. We describe here a child with a juvenile disseminated form of paracoccidioidomycosis, which showed reticuloendothelial system involvement and the presence of Paracoccidioides brasiliensis in the bone marrow. The patient showed an effective and rapid response to itraconazole therapy. 相似文献
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Valérie Capelle Carine Remoué Laurence Moreau Agnès Reyss Aline Mahé Agnès Massonneau Matthieu Falque Alain Charcosset Claudine Thévenot Peter Rogowsky Sylvie Coursol Jean-Louis Prioul 《BMC plant biology》2010,10(1):1-22
Background
Kernel moisture at harvest is an important trait since a low value is required to prevent unexpected early germination and ensure seed preservation. It is also well known that early germination occurs in viviparous mutants, which are impaired in abscisic acid (ABA) biosynthesis. To provide some insight into the genetic determinism of kernel desiccation in maize, quantitative trait loci (QTLs) were detected for traits related to kernel moisture and ABA content in both embryo and endosperm during kernel desiccation. In parallel, the expression and mapping of genes involved in kernel desiccation and ABA biosynthesis, were examined to detect candidate genes.Results
The use of an intermated recombinant inbred line population allowed for precise QTL mapping. For 29 traits examined in an unreplicated time course trial of days after pollination, a total of 78 QTLs were detected, 43 being related to kernel desiccation, 15 to kernel weight and 20 to ABA content. Multi QTL models explained 35 to 50% of the phenotypic variation for traits related to water status, indicating a large genetic control amenable to breeding. Ten of the 20 loci controlling ABA content colocated with previously detected QTLs controlling water status and ABA content in water stressed leaves. Mapping of candidate genes associated with kernel desiccation and ABA biosynthesis revealed several colocations between genes with putative functions and QTLs. Parallel investigation via RT-PCR experiments showed that the expression patterns of the ABA-responsive Rab17 and Rab28 genes as well as the late embryogenesis abundant Emb5 and aquaporin genes were related to desiccation rate and parental allele effect. Database searches led to the identification and mapping of two zeaxanthin epoxidase (ZEP) and five novel 9-cis-epoxycarotenoid dioxygenase (NCED) related genes, both gene families being involved in ABA biosynthesis. The expression of these genes appeared independent in the embryo and endosperm and not correlated with ABA content in either tissue.Conclusions
A high resolution QTL map for kernel desiccation and ABA content in embryo and endosperm showed several precise colocations between desiccation and ABA traits. Five new members of the maize NCED gene family and another maize ZEP gene were identified and mapped. Among all the identified candidates, aquaporins and members of the Responsive to ABA gene family appeared better candidates than NCEDs and ZEPs. 相似文献114.
Sciutto E Rosas G Cruz-Revilla C Toledo A Cervantes J Hernández M Hernándezt B Goldbaum FA de Aluja AS Fragoso G Larralde C 《The Journal of parasitology》2007,93(4):824-831
Review of experimental and observational evidence about various cestode infections of mammalian hosts revives hope for the development of an effective vaccine against adult intestinal tapeworms, the central protagonists in their transmission dynamics. As for Taenia solium, there are abundant immunological data regarding cysticercosis in humans and pigs, but information about human taeniasis is scarce. A single publication reporting protection against T. solium taeniasis by experimental primo infection and by vaccination of an experimental foster host, the immunocompetent female hamster, kindles the hope of a vaccine against the tapeworm to be used in humans, its only natural definitive host. 相似文献
115.
Gesteira AS Micheli F Carels N Da Silva AC Gramacho KP Schuster I Macêdo JN Pereira GA Cascardo JC 《Annals of botany》2007,100(1):129-140
BACKGROUND AND AIMS: Witches' broom disease is caused by the hemibiotrophic basidiomycete Moniliophthora perniciosa, and is one of the most important diseases of cacao in the western hemisphere. Because very little is known about the global process of such disease development, expressed sequence tags (ESTs) were used to identify genes expressed during the Theobroma cacao-Moniliophthora perniciosa interaction. METHODS: Two cDNA libraries corresponding to the resistant (RT) and susceptible (SP) cacao-M. perniciosa interactions were constructed from total RNA, using the DB SMART Creator cDNA library kit (Clontech). Clones were randomly selected, sequenced from the 5' end and analysed using bioinformatics tools including in silico analysis of the differential gene expression. KEY RESULTS: A total of 6884 ESTs were generated from the RT and SP cDNA libraries. These ESTs were composed of 2585 singlets and 341 contigs for a total of 2926 non-redundant sequences. The redundancy of the libraries was low and their specificity high when compared with the few other cacao libraries already published. Sequence analysis allowed the assignment of a putative functional category for 54 % of sequences, whereas approx. 22 % of sequences corresponded to unknown function and approx. 24 % of sequences did not show any significant similarity with other proteins present in the database. Despite the similar overall distribution of the sequences in functional categories between the two libraries, qualitative differences were observed. Genes involved during the defence response to pathogen infection or in programmed cell death were identified, such as pathogenesis related-proteins, trypsin inhibitor or oxalate oxidase, and some of them showed an in silico differential expression between the resistant and the susceptible interactions. CONCLUSIONS: As far as is known this is the first EST resource from the cacao-M. perniciosa interaction and it is believed that it will provide a significant contribution to the understanding of the molecular mechanisms of the resistance and susceptibility of cacao to M. perniciosa, to develop strategies to control witches' broom, and as a source of polymorphism for molecular marker development and marker-assisted selection. 相似文献
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Kelitha Maxis Aline Delalandre Johanne Martel-Pelletier Jean-Pierre Pelletier Nicolas Duval Daniel Lajeunesse 《Arthritis research & therapy》2007,8(6):R181
Osteoarthritis (OA) is characterized by articular cartilage degradation and hypertrophic bone changes with osteophyte formation
and abnormal bone remodeling. Two groups of OA patients were identified via the production of variable and opposite levels
of prostaglandin E2 (PGE2) or leukotriene B4 (LTB4) by subchondral osteoblasts, PGE2 levels discriminating between low and high subgroups. We studied whether the expression of 5-lipoxygenase (5-LO) or 5-LO-activating
protein (FLAP) is responsible for the shunt from prostaglandins to leukotrienes. FLAP mRNA levels varied in low and high OA
groups compared with normal, whereas mRNA levels of 5-LO were similar in all osteoblasts. Selective inhibition of cyclooxygenase-2
(COX-2) with NS-398-stimulated FLAP expression in the high OA osteoblasts subgroup, whereas it was without effect in the low
OA osteoblasts subgroup. The addition of PGE2 to the low OA osteoblasts subgroup decreased FLAP expression but failed to affect it in the high OA osteoblasts subgroup.
LTB4 levels in OA osteoblasts were stimulated about twofold by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plus transforming growth factor-β (TGF-β), a situation corresponding to their effect on FLAP mRNA levels. Treatments with
1,25(OH)2D3 and TGF-β also modulated PGE2 production. TGF-β stimulated PGE2 production in both OA osteoblast groups, whereas 1,25(OH)2D3 alone had a limited effect but decreased the effect of TGF-β in the low OA osteoblasts subgroup. This modulation of PGE2 production was mirrored by the synthesis of COX-2. IL-18 levels were only slightly increased in a subgroup of OA osteoblasts
compared with normal; however, no relationship was observed overall between IL-18 and PGE2 levels in normal and OA osteoblasts. These results suggest that the shunt from the production of PGE2 to LTB4 is through regulation of the expression of FLAP, not 5-LO, in OA osteoblasts. The expression of FLAP in OA osteoblasts is
also modulated differently by 1,25(OH)2D3 and TGF-β depending on their endogenous low and high PGE2 levels. 相似文献
118.
RNA interference (RNAi) is widely used in Caenorhabditis elegans to identify gene function and has been adapted as a high-throughput screening method to identify genes involved in essential processes. The technique has been applied to parasitic nematodes with variable success and we believe that inconsistent outcomes preclude its use as a robust screen with which to identify potential control targets. In this article, key issues that require clarification are discussed, including the mode of delivery of double-stranded RNA to the parasite, the developmental stage targeted and, perhaps of most importance, whether the RNAi pathway (as defined by studies in C. elegans) is fully functional in some parasitic nematodes. 相似文献
119.
Evaluation of blood pressure in feline night monkeys (Aotus azarae infulatus) under different restraint protocols
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