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101.
102.
Albouy G Sterpenich V Balteau E Vandewalle G Desseilles M Dang-Vu T Darsaud A Ruby P Luppi PH Degueldre C Peigneux P Luxen A Maquet P 《Neuron》2008,58(2):261-272
Functional magnetic resonance imaging (fMRI) was used to investigate the cerebral correlates of motor sequence memory consolidation. Participants were scanned while training on an implicit oculomotor sequence learning task and during a single testing session taking place 30 min, 5 hr, or 24 hr later. During training, responses observed in hippocampus and striatum were linearly related to the gain in performance observed overnight, but not over the day. Responses in both structures were significantly larger at 24 hr than at 30 min or 5 hr. Additionally, the competitive interaction observed between these structures during training became cooperative overnight. These results stress the importance of both hippocampus and striatum in procedural memory consolidation. Responses in these areas during training seem to condition the overnight memory processing that is associated with a change in their functional interactions. These results show that both structures interact during motor sequence consolidation to optimize subsequent behavior. 相似文献
103.
Some 2-amino-4,6-diarylpyrimidines 2 have been prepared from substituted benzylideneacetophenones and guanidine hydrochloride in the presence of alkali by conventional heating in alcoholic medium and microwave heating in solvent-free conditions. N-(2,3,4,6-Tetra-O-acetyl-β-d-glucopyranosyl)-N′-(4′,6′-diarylpyrimidin-2′-yl)thioureas 4 have been synthesized by reaction of per-O-acetylated glucopyranosyl isothiocyanate 1 and substituted 2-amino-4,6-diarylpyrimidines 2. Two different methods have been used, namely, refluxing in anhydrous dioxane and solvent-free microwave-assisted coupling. The second procedure afforded higher yields in much shorter reaction times. The compounds 2 and 4 were tested for their antibacterial and antifungal activities in vitro against Staphylococcus epidermidis, Enterobacter aerogenes and Candida albicans by disc diffusion method. 相似文献
104.
Thi Thanh Hien Dao Roberto Chacon Puig Hye Kyong Kim Cornelis Erkelens Alfons W.M. Lefeber Huub J.M. Linthorst Young Hae Choi Robert Verpoorte 《Plant Physiology and Biochemistry》2009,47(2):146-152
Benzothiadiazole (BTH) is a functional analog of the plant endogenous hormone-like compound, salicylic acid (SA), which is required for the induction of plant defense genes leading to systemic acquired resistance (SAR). Previous molecular and genetic studies have suggested that BTH itself might potentiate SAR resulting in the induction of several pathogenesis-related (PR) genes. However, the changes in the metabolome, which occur as a result of BTH-treatment, remain unclear. In this study, metabolic alterations in BTH-treated Arabidopsis thaliana were investigated using nuclear magnetic resonance (NMR) spectroscopy followed by multivariate data analyses such as principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA). Both PCA and PLS-DA show that increase of glucose, glutamine, inositol, malic acid, sucrose, and threonine as well as BTH and its degraded metabolites contribute to the clear discrimination of the metabolome of BTH-treated Arabidopsis from control plants. However, the levels of phenolic metabolites, which have generally been observed to be induced by other signaling molecules were significantly reduced in BTH-treated Arabidopsis. In addition to these changes due to BTH-treatment, it was also found that the EtOH used as a solvent in this treatment may per se act as an inducer of the accumulation of a flavonoid. 相似文献
105.
The majority of Hevea (Hevea brasiliensis Muell. Arg.) genetic resource in Vietnam derived from the IRRDB’81 germplasm collected in the Amazonian habitats of the genus.
Random amplified polymorphic DNA (RAPD) analysis was used to examine the genetic diversity and structure of the IRRDB’81 germplasm.
A total of 59 accessions from 13 different districts of the Brazilian states namely Acre, Rondonia, and Mato Grosso were brought
into the study using six arbitrarily preselected primers. Sixty-five RAPD band patterns ranging in size from 0.2 to 3.0 kbp
were scored for analysis. Differences in the level of DNA polymorphism among the districts and states were revealed. The percentage
of the polymorphic DNA fragments calculated for 13 individual districts varied from 15.38 to 70.77%. The mean values of heterozygosity
within the district varied from 0.064 to 0.264. Pairwise district Nei’s genetic distance values ranged from 0.046 for Catriquacu
and Itanba of Mato Grosso to 0.304 for Tarauaca of Acre and Aracatuba of Mato Grosso. The estimated values of Shannon’s diversity
index ranged from 0.093 for the Assis-Brasil district of Acre to 0.389 for the Jiparana district of Rondonia. The analysis
of molecular variance (AMOVA) indicated that most of the genetic variations were found among accessions within the districts,
while interdistrict variance component accounted for 14.1% only. The low interdistrict differentiation probably implied an
extensive gene flow among them. Both the principal coordinate analysis and UPGMA cluster analysis based on genetic distance
values revealed a varying degree of separation among the districts and that conformed to geographical origins of Hevea IRRDB’81 collection. 相似文献
106.
Hendrik-Jan Megens Richard PMA Crooijmans John WM Bastiaansen Hindrik HD Kerstens Albart Coster Ruud Jalving Addie Vereijken Pradeepa Silva William M Muir Hans H Cheng Olivier Hanotte Martien AM Groenen 《BMC genetics》2009,10(1):1-11
Background
Toll like receptors (TLR) play the central role in the recognition of pathogen associated molecular patterns (PAMPs). Mutations in the TLR1, TLR2 and TLR4 genes may change the ability to recognize PAMPs and cause altered responsiveness to the bacterial pathogens.Results
The study presents association between TLR gene mutations and increased susceptibility to Mycobacterium avium subsp. paratuberculosis (MAP) infection. Novel mutations in TLR genes (TLR1- Ser150Gly and Val220Met; TLR2 – Phe670Leu) were statistically correlated with the hindrance in recognition of MAP legends. This correlation was confirmed subsequently by measuring the expression levels of cytokines (IL-4, IL-8, IL-10, IL-12 and IFN-γ) in the mutant and wild type moDCs (mocyte derived dendritic cells) after challenge with MAP cell lysate or LPS. Further in silico analysis of the TLR1 and TLR4 ectodomains (ECD) revealed the polymorphic nature of the central ECD and irregularities in the central LRR (leucine rich repeat) motifs.Conclusion
The most critical positions that may alter the pathogen recognition ability of TLR were: the 9th amino acid position in LRR motif (TLR1–LRR10) and 4th residue downstream to LRR domain (exta-LRR region of TLR4). The study describes novel mutations in the TLRs and presents their association with the MAP infection. 相似文献107.
Constance Schultsz Nguyen Van Dung Le Thanh Hai Do Quang Ha J. S. Malik Peiris Wilina Lim Jean-Michel Garcia Nguyen Dac Tho Nguyen Thi Hoang Lan Huynh Huu Tho Phan Xuan Thao H. Rogier van Doorn Nguyen Van Vinh Chau Jeremy Farrar Menno D. de Jong 《PloS one》2009,4(11)
Background
Between 2003 and 2005, highly pathogenic avian influenza A (H5N1) viruses caused large scale outbreaks in poultry in the Ho Chi Minh City area in Vietnam. We studied the prevalence of antibodies against H5N1 in poultry workers and cullers who were active in the program in Ho Chi Minh City in 2004 and 2005.Methodology/Principal Findings
Single sera from 500 poultry workers and poultry cullers exposed to infected birds were tested for antibodies to avian influenza H5N1, using microneutralization assays and hemagglutination inhibition assay with horse blood. All sera tested negative using microneutralization tests. Three samples showed a 1∶80 titer in the hemagglutination inhibition assay.Conclusions/Significance
This study provides additional support for the low transmissibility of clade 1 H5N1 to humans, but limited transmission to highly exposed persons cannot be excluded given the presence of low antibody titers in some individuals. 相似文献108.
Truc Thi Kim Thanh Hoang Anneline Nansen Sugata Roy Rolf Billeskov Claus Aagaard Tara Elvang Jes Dietrich Peter Andersen 《PloS one》2009,4(6)
Background
Recently we and others have identified CD8 and CD4 T cell epitopes within the highly expressed M. tuberculosis protein TB10.4. This has enabled, for the first time, a comparative study of the dynamics and function of CD4 and CD8 T cells specific for epitopes within the same protein in various stages of TB infection.Methods and Findings
We focused on T cells directed to two epitopes in TB10.4; the MHC class I restricted epitope TB10.4 3–11 (CD8/10.4 T cells) and the MHC class II restricted epitope TB10.4 74–88 (CD4/10.4 T cells). CD4/10.4 and CD8/10.4 T cells displayed marked differences in terms of expansion and contraction in a mouse TB model. CD4/10.4 T cells dominated in the early phase of infection whereas CD8/10.4 T cells were expanded after week 16 and reached 5–8 fold higher numbers in the late phase of infection. In the early phase of infection both CD4/10.4 and CD8/10.4 T cells were characterized by 20–25% polyfunctional cells (IL-2+, IFN-γ+, TNF-α+), but whereas the majority of CD4/10.4 T cells were maintained as polyfunctional T cells throughout infection, CD8/10.4 T cells differentiated almost exclusively into effector cells (IFN-γ+, TNF-α+). Both CD4/10.4 and CD8/10.4 T cells exhibited cytotoxicity in vivo in the early phase of infection, but whereas CD4/10.4 cell mediated cytotoxicity waned during the infection, CD8/10.4 T cells exhibited increasing cytotoxic potential throughout the infection.Conclusions/Significance
Our results show that CD4 and CD8 T cells directed to epitopes in the same antigen differ both in their kinetics and functional characteristics throughout an infection with M. tuberculosis. In addition, the observed strong expansion of CD8 T cells in the late stages of infection could have implications for the development of post exposure vaccines against latent TB. 相似文献109.
110.
Tran Tinh Hien Nguyen Thi Dung Nguyen Thanh Truong Ninh Thi Thanh Van Tran Nguyen Bich Chau Nguyen Van Minh Hoang Tran Thi Thu Nga Cao Thu Thuy Pham Van Minh Nguyen Thi Cam Binh Tran Thi Diem Ha Pham Van Toi To Song Diep James I. Campbell Elaine Stockwell Constance Schultsz Cameron P. Simmons Clare Glover Winnie Lam Filipe Marques James P. May Anthony Upton Ronald Budhram Gordon Dougan Jeremy Farrar Nguyen Van Vinh Chau Christiane Dolecek 《PloS one》2010,5(7)