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91.
Detlef Michel Hans Hartings Simona Lanzini Manuela Michel Mario Motto Giorgia Romina Riboldi Francesco Salamini Hans-Peter Döring 《Molecular & general genetics : MGG》1995,248(3):287-292
Eight independently isolated unstable alleles of theOpaque2 (O2) locus were analysed genetically and at the DNA level. The whole series of mutations was isolated from a maize strain carrying a wild-typeO2 allele and the transposable elementActivator (Ac) at thewx-m7 allele. Previous work with another unstable allele of the same series has shown that it was indeed caused by the insertion of anAc element. Unexpectedly, the remaining eight mutations were not caused by the designatedAc element, but by other insertions that are structurally similar or identical to one of two different autonomous transposable elements. Six mutations were caused by the insertion of a transposable element of theEnhancer/Suppressor-Mutator (En/Spm) family. Two mutations were the result of the insertion of a transposable element of theBergamo (Bg) family. Genetic tests carried out with plants carrying the unstable mutations demonstrated that all were caused by the insertion of an autonomous transposable element. 相似文献
92.
93.
Radi M Crespan E Botta G Falchi F Maga G Manetti F Corradi V Mancini M Santucci MA Schenone S Botta M 《Bioorganic & medicinal chemistry letters》2008,18(3):1207-1211
A series of substituted benzoylamino-2-[(4-benzyl)thio]-1,3,4-thiadiazoles has been discovered as potent Abl tyrosine kinase inhibitors. Molecular docking simulations on the Abl tyrosine kinase were conducted in order to rationalize the SAR of the synthesized inhibitors. The most active compound identified from the enzymatic screening (6a) showed interesting inhibitory activity on Imatinib-sensitive murine myeloid 3B clone and Bcr-Abl-independent Imatinib-resistant leukemia cells. Surprisingly, 6a was also proved to act as differentiating inducers in human promyelocytic leukemia cells (HL-60). 相似文献
94.
Manuela Polimeni Elena Valente Daniela Ulliers Ghislain Opdenakker Philippe E. Van den Steen Giuliana Giribaldi Mauro Prato 《PloS one》2013,8(8)
Recently matrix metalloproteinase-9 (MMP-9) and its endogenous inhibitor (tissue inhibitor of metalloproteinase-1, TIMP-1) have been implicated in complicated malaria. In vivo, mice with cerebral malaria (CM) display high levels of both MMP-9 and TIMP-1, and in human patients TIMP-1 serum levels directly correlate with disease severity. In vitro, natural haemozoin (nHZ, malarial pigment) enhances monocyte MMP-9 expression and release. The present study analyses the effects of nHZ on TIMP-1 regulation in human adherent monocytes. nHZ induced TIMP-1 mRNA expression and protein release, and promoted TNF-α, IL-1β, and MIP-1α/CCL3 production. Blocking antibodies or recombinant cytokines abrogated or mimicked nHZ effects on TIMP-1, respectively. p38 MAPK and NF-κB inhibitors blocked all nHZ effects on TIMP-1 and pro-inflammatory molecules. Still, total gelatinolytic activity was enhanced by nHZ despite TIMP-1 induction. Collectively, these data indicate that nHZ induces inflammation-mediated expression and release of human monocyte TIMP-1 through p38 MAPK- and NF-κB-dependent mechanisms. However, TIMP-1 induction is not sufficient to counterbalance nHZ-dependent MMP-9 enhancement. Future investigation on proteinase-independent functions of TIMP-1 (i.e. cell survival promotion and growth/differentiation inhibition) is needed to clarify the role of TIMP-1 in malaria pathogenesis. 相似文献
95.
Manuela Gellert Simone Venz Jessica Mitl?hner Catherine Cott Eva-Maria Hanschmann Christopher Horst Lillig 《The Journal of biological chemistry》2013,288(49):35117-35125
Vertebrate-specific glutaredoxin 2 (Grx2) is expressed in at least two isoforms, mitochondrial Grx2a and cytosolic Grx2c. We have previously shown that cytosolic Grx2 is essential for embryonic development of the brain. In particular, we identified collapsin response mediator protein 2 (CRMP2/DPYSL2), a mediator of the semaphorin-plexin signaling pathway, as redox-regulated target of Grx2c and demonstrated that this regulation is required for normal axonal outgrowth. In this study, we demonstrate the molecular mechanism of this regulation, a specific and reversible intermolecular Cys-504-Cys-504 dithiol-disulfide switch in homotetrameric CRMP2. This switch determines two conformations of the quaternary CRMP2 complex that controls axonal outgrowth and thus neuronal development. 相似文献
96.
The objective of this study was to evaluate differences in correlations among Biological Elements and environmental parameters
for different river types, analysed at two different spatial scales. A total of 82 sites, with at least good ecological status,
were sampled across Europe, representing three core river types: Mountain rivers (26 sites); Lowland rivers (29 sites) and
Mediterranean rivers (17 sites). At each site samples of macrophytes, macroinvertebrates and fishes were taken during spring,
following the methodological procedures established by the European STAR project. Environmental parameters were also recorded,
based on a site protocol developed by the European projects AQEM and STAR. Environmental parameters were divided into three
categories: aquatic habitats (mesohabitat scale), global features (reach scale) and obligatory typology parameters of Water
Framework Directive (WFD) (geographical scale). Data were analysed to evaluate at the two scales, first, relationships among
biological elements, and second, relationships between biological elements and environmental parameters. Within each river
type, correlation matrices (Bray–Curtis distance) were calculated separately for each biological element and for each category
of environmental parameters. All biological elements were correlated (p<0.01) to the larger spatial scale: macrophytes and macroinvertebrates are more correlated in lowland and mountain rivers,
while in Mediterranean rivers, fish and macrophytes presented higher correlations. These links tend to be consistent for different
spatial scales, except if they are weak on a larger regional scale, obligatory parameters of WFD were, in most cases, significantly
correlated with the three biological communities (p<0.05). Results at different spatial scales supported the hierarchical theory of river formation. Reach and mesohabitat environmental
parameters tend to explain aquatic communities at a lower spatial scale, while geographical parameters tend to explain the
communities at a major spatial scale. 相似文献
97.
Expression systems and developments in plant-made vaccines 总被引:5,自引:0,他引:5
Delivery of vaccines to mucosal surfaces can elicit humoral and cell-mediated responses of the mucosal and systemic immune systems, evoke less pain and discomfort than parenteral delivery, and eliminate needle-associated risks. Transgenic plants are an ideal means by which to produce oral vaccines, as the rigid walls of the plant cell protect antigenic proteins from the acidic environment of the stomach, enabling intact antigen to reach the gut associated lymphoid tissue. In the past few years, new techniques (such as chloroplast transformation and food processing) have improved antigen concentration in transgenic plants. In addition, adjuvants and targeting proteins have increased the immunogenicity of mucosally administered plant-made vaccines. These studies have moved plant-made vaccines closer to the development phase. 相似文献
98.
99.
Beck-Speier I Dayal N Karg E Maier KL Schumann G Schulz H Semmler M Takenaka S Stettmaier K Bors W Ghio A Samet JM Heyder J 《Free radical biology & medicine》2005,38(8):1080-1092
In ambient aerosols, ultrafine particles (UFP) and their agglomerates are considered to be major factors contributing to adverse health effects. Reactivity of agglomerated UFP of elemental carbon (EC), Printex 90, Printex G, and diesel exhaust particles (DEP) was evaluated by the capacity of particles to oxidize methionine in a cell-free in vitro system for determination of their innate oxidative potential and by alveolar macrophages (AMs) to determine production of arachidonic acid (AA), including formation of prostaglandin E2 (PGE2), leukotriene B4 (LTB4), reactive oxygen species (ROS), and oxidative stress marker 8-isoprostane. EC exhibiting high oxidative potential induced generation of AA, PGE2, LTB4, and 8-isoprostane in canine and human AMs. Printex 90, Printex G, and DEP, showing low oxidative capacity, still induced formation of AA and PGE2, but not that of LTB4 or 8-isoprostane. Aging of EC lowered oxidative potential while still inducing production of AA and PGE2 but not that of LTB4 and 8-isoprostane. Cellular ROS production was stimulated by all particles independent of oxidative potential. Particle-induced formation of AA metabolites and ROS was dependent on mitogen-activated protein kinase kinase 1 activation of cytosolic phospholipase A2 (cPLA2) as shown by inhibitor studies. In conclusion, cPLA2, PGE2, and ROS formation was activated by all particle types, whereas LTB4 production and 8-isoprostane were strongly dependent on particles' oxidative potential. Physical and chemical parameters of particle surface correlated with oxidative potential and stimulation of AM PGE2 and 8-isoprostane production. 相似文献
100.