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51.
Dolores Solis Juan J Calvete Libia Sanz Christiane Hettel Manfred Raida Teresa Diaz-Maurino Edda Topfer-Petersen 《Glycoconjugate journal》1997,14(2):275-280
Lectin mapping, carbohydrate analysis and electrospray mass spectrometry of boar seminal plasma PSP-II glycoforms show that
its single N-glycosylation site displays a repertoire of carbohydrate structures consisting of the basic pentasaccharide core
Manα 1–6[Manα 1–3]Manβ1-4GlcNAcβ1-4GlcNAc with a fucosyl residue α1-6-linked to the innermost N-acetylglucosamine residue. Other glycoforms display fucosylated hybrid-type or monoantennary complex-type chains, some of
which contain α2-6-linked sialic acid. N-acetylgalactosamine, possibly in Galβ1-3GalNAc sequence, is present in most of the PSP-II glycoforms. Abbreviations: PSP-I and PSP-II, porcine seminal plasma proteins
I and II; PNGaseF, peptide-N4-(N-acetyl-β-D-glucosaminyl) asparagine amidase (EC 3.5.1.52) from Flavobacterium meningosepticum;
ConA, Cannavalia ensiformis (jack bean) agglutinin; GNA, Galanthus nivalis (snowdrop) agglutin; SNA, Sambucus nigra (elderberry)
agglutinin; MAA, Maackia amurensis (maakia) agglutinin; PNA, Arachis hypogaea (peanut) agglutinin; DSA, Datura stramonium
(jimson weed) agglutinin; AAA, Aleuria aurantia agglutinin
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
52.
Gianluca Matteoli Edda Fahl Philipp Warnke Steffen Müller Michael Bonin Ingo B Autenrieth Erwin Bohn 《BMC microbiology》2008,8(1):153
Background
Yersinia outer protein (Yop) H is a secreted virulence factor of Yersinia enterocolitica (Ye), which inhibits phagocytosis of Ye and contributes to the virulence of Ye in mice. The aim of this study was to address whether and how YopH affects the innate immune response to Ye in mice. 相似文献53.
Böttcher C von Roepenack-Lahaye E Schmidt J Schmotz C Neumann S Scheel D Clemens S 《Plant physiology》2008,147(4):2107-2120
Metabolomics is facing a major challenge: the lack of knowledge about metabolites present in a given biological system. Thus, large-scale discovery of metabolites is considered an essential step toward a better understanding of plant metabolism. We show here that the application of a metabolomics approach generating structural information for the analysis of Arabidopsis (Arabidopsis thaliana) mutants allows the efficient cataloging of metabolites. Fifty-six percent of the features that showed significant differences in abundance between seeds of wild-type, transparent testa4, and transparent testa5 plants could be annotated. Seventy-five compounds were structurally characterized, 21 of which could be identified. About 40 compounds had not been known from Arabidopsis before. Also, the high-resolution analysis revealed an unanticipated expansion of metabolic conversions upstream of biosynthetic blocks. Deficiency in chalcone synthase results in the increased seed-specific biosynthesis of a range of phenolic choline esters. Similarly, a lack of chalcone isomerase activity leads to the accumulation of various naringenin chalcone derivatives. Furthermore, our data provide insight into the connection between p-coumaroyl-coenzyme A-dependent pathways. Lack of flavonoid biosynthesis results in elevated synthesis not only of p-coumarate-derived choline esters but also of sinapate-derived metabolites. However, sinapoylcholine is not the only accumulating end product. Instead, we observed specific and sophisticated changes in the complex pattern of sinapate derivatives. 相似文献
54.
Many external signals influence growth cone motility, pathfinding, and the formation of synapses that lead to the final map formation of the retinotectal system. Chick temporal retinal ganglion cell axons (RGCs) collapse and retract after encountering posterior tectal cells in vitro. During this process lateral extensions appear along the RGC axonal shaft. Lateral extensions appear as nascent interstitial axonal branches and also as defasciculating growth cones that are trailing along the pioneer axon. RGC branching controlled by repellent tectal cues has recently been shown to be the critical event in retinotectal map development. The intracellular mechanism underlying this phenomenon, however, is not understood. Inhibiting RhoA with either C3 toxin or inhibiting p160Rock kinase, an effector of RhoA, with Y27632 inhibited collapse, retraction, and the number of axons that showed lateral extensions. Lateral extension length increased significantly. Inhibiting Rac1A and cdc42 with cell permeable peptide inhibitors did not inhibit collapse of growth cones, but did inhibit axon retraction. In addition, the number of axons that showed lateral extensions and lateral extension length were significantly reduced. A dynamic cytoskeleton is necessary to react to incoming guidance information. This study addresses the problems of how growth cone motility and branching or defasciculation are affected by Rho‐GTPases as extracellular signals are transmitted to the cytoskeleton. © 2002 Wiley Periodicals, Inc. J Neurobiol 54: 358–369, 2003 相似文献
55.
56.
Dorothee von Witzendorff Kai Maass Andreas Pich Silja Ebeling Sabine Klle Christine Kochel Mahnaz Ekhlasi-Hundrieser Hildegard Geyer Rudolf Geyer Edda Tpfer-Petersen 《Carbohydrate research》2009,344(12):1541-751
Oocyte maturation is a prerequisite for successful fertilization. Growing evidence suggests that not only the oocyte but also the surrounding zona pellucida has to undergo maturational changes. In the pig, two-dimensional electrophoretic analysis demonstrated an acidic shift of the zona pellucida glycoproteins of about 1.5–2.0 pH units during the maturation process. These findings were corroborated by histological studies that indicated the synthesis of acidic glycoconjugates in the cumulus cells and an increased occurrence of acidic glycans in the zona pellucida after oocyte maturation. In order to provide structural data on prepuberal zona pellucida N-glycosylation, N-glycans were released from prepuberal zona pellucida glycoproteins by N-glycosidase F and studied by mass spectrometry before and after desialylation and treatment with endo-β-galactosidase. Our results verified the presence of high-mannose-type Man5GlcNAc2 compounds as well as diantennary N-glycans as major neutral species, whereas sialylated diantennary and triantennary species constituted the dominant non-sulfated acidic sugar chains. The major acidic N-glycans of prepuberal animals, however, represented mono-sulfated diantennary, triantennary and tetraantennary oligosaccharides carrying, in part, N-acetyllactosamine repeating units as well as additional Neu5Ac or Neu5Gc residues. Glycans comprising more than one sulfate residue were not detected. In contrast to the literature data on zona pellucida glycoprotein-N-glycans of cyclic animals, our data thus reveal a lower degree in glycan sulfation of the prepuberal zona pellucida. 相似文献
57.
Agnès Fleury Jael Moreno García Paulina Valdez Aguerrebere María de Sayve Durán Paola Becerril Rodríguez Carlos Larralde Edda Sciutto 《PLoS neglected tropical diseases》2010,4(8)
Background
The ongoing epidemiological transition in Mexico minimizes the relative impact of neurocysticercosis (NC) on public health. However, hard data on the disease frequency are not available.Methodology
All clinical records from patients admitted in the Instituto Nacional de Neurologia y Neurocirugia (INNN) at Mexico City in 1994 and 2004 were revised. The frequencies of hospitalized NC patients in neurology, neurosurgery and psychiatry services, as well as NC mortality from 1995 through 2009, were retrieved. Statistical analyses were made to evaluate possible significant differences in frequencies of NC patients'' admission between 1994 and 2004, and in yearly frequencies of NC patients'' hospitalization and death between 1995 and 2009.Principal Findings
NC frequency in INNN is not significantly different in 1994 and 2004. Between these two years, clinical severity of the cases diminished and the proportion of patients living in Mexico City increased. Yearly frequencies of hospitalization in neurology and psychiatry services were stable, while frequencies of hospitalization in neurosurgery service and mortality significantly decreased between 1995 and 2009.Conclusions
Our findings show a stable tendency of hospital cases during the last decade that should encourage to redouble efforts to control this ancient disease. 相似文献58.
59.
60.
David Dweck Marcos A. Sanchez-Gonzalez Audrey N. Chang Raul A. Dulce Crystal-Dawn Badger Andrew P. Koutnik Edda L. Ruiz Brittany Griffin Jingsheng Liang Mohamed Kabbaj Frank D. Fincham Joshua M. Hare J. Michael Overton Jose R. Pinto 《The Journal of biological chemistry》2014,289(33):23097-23111
The cardiac troponin I (cTnI) R21C (cTnI-R21C) mutation has been linked to hypertrophic cardiomyopathy and renders cTnI incapable of phosphorylation by PKA in vivo. Echocardiographic imaging of homozygous knock-in mice expressing the cTnI-R21C mutation shows that they develop hypertrophy after 12 months of age and have abnormal diastolic function that is characterized by longer filling times and impaired relaxation. Electrocardiographic analyses show that older R21C mice have elevated heart rates and reduced cardiovagal tone. Cardiac myocytes isolated from older R21C mice demonstrate that in the presence of isoproterenol, significant delays in Ca2+ decay and sarcomere relaxation occur that are not present at 6 months of age. Although isoproterenol and stepwise increases in stimulation frequency accelerate Ca2+-transient and sarcomere shortening kinetics in R21C myocytes from older mice, they are unable to attain the corresponding WT values. When R21C myocytes from older mice are treated with isoproterenol, evidence of excitation-contraction uncoupling is indicated by an elevation in diastolic calcium that is frequency-dissociated and not coupled to shorter diastolic sarcomere lengths. Myocytes from older mice have smaller Ca2+ transient amplitudes (2.3-fold) that are associated with reductions (2.9-fold) in sarcoplasmic reticulum Ca2+ content. This abnormal Ca2+ handling within the cell may be attributed to a reduction (2.4-fold) in calsequestrin expression in conjunction with an up-regulation (1.5-fold) of Na+-Ca2+ exchanger. Incubation of permeabilized cardiac fibers from R21C mice with PKA confirmed that the mutation prevents facilitation of mechanical relaxation. Altogether, these results indicate that the inability to enhance myofilament relaxation through cTnI phosphorylation predisposes the heart to abnormal diastolic function, reduced accessibility of cardiac reserves, dysautonomia, and hypertrophy. 相似文献