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101.
JF Yuan SJ Zhang O Jafer RA Furlong OE Chausiaux CA Sargent GH Zhang NA Affara 《BMC microbiology》2009,9(1):246
Background
Pseudorabies virus (PRV) is an alphaherpesviruses whose native host is pig. PRV infection mainly causes signs of central nervous system disorder in young pigs, and respiratory system diseases in the adult. 相似文献102.
Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex 总被引:1,自引:0,他引:1
The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S
nuclear ribosomal DNA sequence and the intervening 5.8S region were
sequenced from three individuals in each of eight taxa of the Mimulus
guttatus species complex. Three discrete variants, or "types," of ITS
sequences were found, among which 30%-40% of sites differed, compared with
1%-2% within types. Dot plots indicate that these types were not related by
conspicuous rearrangements or inversions. More than one ITS type was often
found in the same taxon, and two of three ITS types span species
boundaries, indicating their presence prior to speciation. These ITS
sequences showed essentially no positional homology with the nearest
sequenced relative, tomato. In contrast, the 5.8S region was relatively
unvaried, with 8 of 162 sites varied in the sample among all eight taxa.
The phylogeny inferred by the most common ITS sequence type, rooted by the
two other ITS types, agreed with isozymes in showing the distinctness of M.
nudatus, M. laciniatus, and M. tilingii from the other five taxa.
相似文献
103.
Kantor R Katzenstein DA Efron B Carvalho AP Wynhoven B Cane P Clarke J Sirivichayakul S Soares MA Snoeck J Pillay C Rudich H Rodrigues R Holguin A Ariyoshi K Bouzas MB Cahn P Sugiura W Soriano V Brigido LF Grossman Z Morris L Vandamme AM Tanuri A Phanuphak P Weber JN Pillay D Harrigan PR Camacho R Schapiro JM Shafer RW 《PLoS medicine》2005,2(4):e112
BackgroundThe genetic differences among HIV-1 subtypes may be critical to clinical management and drug resistance surveillance as antiretroviral treatment is expanded to regions of the world where diverse non-subtype-B viruses predominate.ConclusionGlobal surveillance and genotypic assessment of drug resistance should focus primarily on the known subtype B drug-resistance mutations. 相似文献
104.
Presenilin couples the paired phosphorylation of beta-catenin independent of axin: implications for beta-catenin activation in tumorigenesis 总被引:8,自引:0,他引:8
The Alzheimer's disease-linked gene presenilin 1 (PS1) is required for intramembrane proteolysis of APP and Notch. In addition, recent observations strongly implicate PS1 as a negative regulator of the Wnt/beta-catenin signaling pathway, although the mechanism underlying this activity is unknown. Here, we show that presenilin functions as a scaffold that rapidly couples beta-catenin phosphorylation through two sequential kinase activities independent of the Wnt-regulated Axin/CK1alpha complex. Thus, presenilin deficiency results in increased beta-catenin stability in vitro and in vivo by disconnecting the stepwise phosphorylation of beta-catenin, both in the presence and absence of Wnt stimulation. These findings highlight an aspect of beta-catenin regulation outside of the canonical Wnt-regulated pathway and a function of presenilin separate from intramembrane proteolysis. 相似文献
105.
David Bueno Lluis Espinosa Marc Aureli Soriano Eduard Batlle Jaume Baguñà Rafael Romero 《Hydrobiologia》1995,305(1-3):235-240
We have produced monoclonal antibodies (mAbs) against antigens of the freshwater planarian Dugesia (G.) tigrina (Girard) using standard protocols. One of these mAbs, TCEN-49, detects an antigen (TCEN-49Ag) present in most cells of the central area of the body, including the pharynx. Labelled cells seem more related by position than by lineage, suggesting that TCEN-49Ag is involved somehow in the expression of central body positional identity. The spatial and temporal changes in TCEN-49Ag expression during growth/degrowth and regeneration have been monitored and the implications of these results are discussed. 相似文献
106.
107.
Jorge Soriano María García-Díaz Margarita Mora Maria Lluïsa Sagristá Santi Nonell Angeles Villanueva Juan Carlos Stockert Magdalena Cañete 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
The cell death pathway activated after photodynamic therapy (PDT) is controlled by a variety of parameters including the chemical structure of the photosensitizer, its subcellular localization, and the photodynamic damage induced. The present study aims to characterize a suitable m-THPPo liposomal formulation, to determine its subcellular localization in HeLa cells and to establish the cell death mechanisms that are activated after photodynamic treatments.Methods
Liposomes containing m-THPPo were prepared from a mixture of DPPC and DMPG at a 9:1 molar ratio. In order to procure the best encapsulation efficiency, the m-THPPo/lipid molar ratio was considered. HeLa cells were incubated with liposomal m-THPPo and the subcellular localization of m-THPPo was studied. Several assays such as TUNEL, annexin V/propidium iodide and Hoechst-33258 staining were performed after photodynamic treatments. The apoptotic initiation was assessed by cytochrome c and caspase-2 immunofluorescence.Results
m-THPPo encapsulated in liposomes showed a decrease of the fluorescence and singlet oxygen quantum yields, compared to those of m-THPPo dissolved in tetrahydrofuran. Liposomal m-THPPo showed colocalization with LysoTracker® and it induced photoinactivation of HeLa cells by an apoptotic mechanism. In apoptotic cells no relocalization of cytochrome c could be detected, but caspase-2 was positive immediately after photosensitizing treatments.Conclusions
Photodynamic treatment with liposomal m-THPPo leads to a significant percentage of apoptotic morphology of HeLa cells. The activation of caspase-2, without the relocalization of cytochrome c, indicates a mitochondrial-independent apoptotic mechanism.General significance
These results provide a better understanding of the cell death mechanism induced after liposomal m-THPPo photodynamic treatment. 相似文献108.
利用水蒸气蒸馏法提取小黄皮叶挥发油,运用毛细管气相色谱-质谱联用法对挥发油进行了分析,分离出40个峰,鉴定了其中的37种成分,所鉴定成分占挥发油总量的99.87%,其主要化学成分为单萜及倍半萜类化合物。 相似文献
109.
Jose V Llorens Jonathan B Clark Isabel Martínez-Garay Sirena Soriano Rosa de Frutos María J Martínez-Sebastián 《BMC evolutionary biology》2008,8(1):302
Background
Sequences homologous to the gypsy retroelement from Drosophila melanogaster are widely distributed among drosophilids. The structure of gypsy includes an open reading frame resembling the retroviral gene env, which is responsible for the infectious properties of retroviruses. 相似文献110.
Indalecio Quesada‐Soriano Lorien J. Parker Alessandra Primavera Juan M. Casas‐Solvas Antonio Vargas‐Berenguel Carmen Barón Craig J. Morton Anna Paola Mazzetti Mario Lo Bello Michael W. Parker Luis García‐Fuentes 《Protein science : a publication of the Protein Society》2009,18(12):2454-2470
The effect of the Y108V mutation of human glutathione S‐transferase P1‐1 (hGST P1‐1) on the binding of the diuretic drug ethacrynic acid (EA) and its glutathione conjugate (EASG) was investigated by calorimetric, spectrofluorimetric, and crystallographic studies. The mutation Tyr 108 → Val resulted in a 3D‐structure very similar to the wild type (wt) enzyme, where both the hydrophobic ligand binding site (H‐site) and glutathione binding site (G‐site) are unchanged except for the mutation itself. However, due to a slight increase in the hydrophobicity of the H‐site, as a consequence of the mutation, an increase in the entropy was observed. The Y108V mutation does not affect the affinity of EASG for the enzyme, which has a higher affinity (Kd ~ 0.5 μM) when compared with those of the parent compounds, K ~ 13 μM, K ~ 25 μM. The EA moiety of the conjugate binds in the H‐site of Y108V mutant in a fashion completely different to those observed in the crystal structures of the EA or EASG wt complex structures. We further demonstrate that the ΔCp values of binding can also be correlated with the potential stacking interactions between ligand and residues located in the binding sites as predicted from crystal structures. Moreover, the mutation does not significantly affect the global stability of the enzyme. Our results demonstrate that calorimetric measurements maybe useful in determining the preference of binding (the binding mode) for a drug to a specific site of the enzyme, even in the absence of structural information. 相似文献