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排序方式: 共有456条查询结果,搜索用时 15 毫秒
31.
Matías Alejandro Molina Ailén Magalí Díaz Christina Hesse Wiebke Ginter María Virginia Gentilini Guillermo Gabriel Nu?ez Andrea Mercedes Canellada Tim Sparwasser Luciana Berod Marisa Silvia Castro Marcela Alejandra Manghi 《PloS one》2015,10(5)
Probiotics can modulate the immune system, conferring beneficial effects on the host. Understanding how these microorganisms contribute to improve the health status is still a challenge. Previously, we have demonstrated that Enterococcus faecalis CECT7121 implants itself and persists in the murine gastrointestinal tract, and enhances and skews the profile of cytokines towards the Th1 phenotype in several biological models. Given the importance of dendritic cells (DCs) in the orchestration of immunity, the aim of this work was to elucidate the influence of E. faecalis CECT7121 on DCs and the outcome of the immune responses. In this work we show that E. faecalis CECT7121 induces a strong dose-dependent activation of DCs and secretion of high levels of IL-12, IL-6, TNFα, and IL-10. This stimulation is dependent on TLR signaling, and skews the activation of T cells towards the production of IFNγ. The influence of this activation in the establishment of Th responses in vivo shows the accumulation of specific IFNγ-producing cells. Our findings indicate that the activation exerted by E. faecalis CECT7121 on DCs and its consequence on the cellular adaptive immune response may have broad therapeutic implications in immunomodulation. 相似文献
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Gunther Zischinsky Frank Osterkamp Doerte Vossmeyer Grit Zahn Dirk Scharn Ariane Zwintscher Roland Stragies 《Bioorganic & medicinal chemistry letters》2010,20(1):65-68
Recently, a new class of selective integrin α5β1inhibitors consisting of a heterocyclic based scaffold was published. Herein the SAR and pharmacokinetic profiles of N-phenyl piperidine derivatives are described. 相似文献
35.
Chang N Sutherland C Hesse E Winkfein R Wiehler WB Pho M Veillette C Li S Wilson DP Kiss E Walsh MP 《American journal of physiology. Cell physiology》2007,292(4):C1417-C1430
S100A11 is a member of the S100 family of EF-hand Ca2+-binding proteins, which is expressed in smooth muscle and other tissues. Ca2+ binding to S100A11 induces a conformational change that exposes a hydrophobic surface for interaction with target proteins. Affinity chromatography with immobilized S100A11 was used to isolate a 70-kDa protein from smooth muscle that bound to S100A11 in a Ca2+-dependent manner and was identified by mass spectrometry as annexin A6. Direct Ca2+-dependent interaction between S100A11 and annexin A6 was confirmed by affinity chromatography of the purified bacterially expressed proteins, by gel overlay of annexin A6 with purified S100A11, by chemical cross-linking, and by coprecipitation of S100A11 with annexin A6 bound to liposomes. The expression of S100A11 and annexin A6 in the same cell type was verified by RT-PCR and immunocytochemistry of isolated vascular smooth muscle cells. The site of binding of S100A11 on annexin A6 was investigated by partial tryptic digestion and deletion mutagenesis. The unique NH2 terminal head region of annexin A6 was not required for S100A11 binding, but binding sites were identified in both NH2- and COOH-terminal halves of the molecule. We hypothesize that an agonist-induced increase in cytosolic free [Ca2+] leads to formation of a complex of S100A11 and annexin A6, which forms a physical connection between the plasma membrane and the cytoskeleton, or plays a role in the formation of signaling complexes at the level of the sarcolemma. smooth muscle; protein-protein interaction 相似文献
36.
The fossil record of Araceae pollen beginning in the late Early Cretaceous and peaking in the Paleocene/Eocene is very sparse
up to now, consisting of three highly distinctive types: zona-aperturate pollen of the Monstera or Gonatopus type (very similar to Proxapertites operculatus), an ulcerate-spiny type typical for Limnobiophyllum, and a polyplicate, omniaperturate pollen type (an ephedroid pollen with non-gnetalean affinities) which was recently reported
from the late Early Cretaceous (Mayoa portugallica). An extensive literature search has shown that some distinctive Ephedripites forms (the Paleogene Ephedripites vanegensis, and the Late Cretaceous Ephedripites elsikii) are very similar to pollen of Spathiphyllum and both species are here transferred from Ephedripites to Spathiphyllum (as comb. nov.). We also add new fossil findings to the Araceae record. The new findings include a zona-aperturate, microperforate
to microreticulate pollen type from the Palaeocene of Colombia, highly similar to extant Gonatopus or Zamioculcas or Monstera pollen (Araceae) and to fossil Proxapertites operculatus, which is currently seen as a fossil equivalent; and, an ulcerate, spiny pollen from the Eocene of Stolzenbach, Germany,
extending the range of Limnobiophyllum (Pandaniidites), which is thought to be an extinct member of extant Araceae. The three pollen types add considerably to the reliable fossil
record of the family that now contains more than 20 records of these three pollen types: with the zona-aperturate type recorded
from the tropical or subtropical regions of Northern and Southern America, Central Africa, Southern and Central Europe, from
the Indian subcontinent and the Malayan Archipelago; the ulcerate type occurring in North America and Europe; and the polyplicate
type mainly occurring in South America and South-West Europe. Now we have good evidence that some of the aroid subfamilies
were already in existence in the Cretaceous, increasing in diversity and worldwide distribution in the Paleogene.
Dedicated to Prof. Dr. Stefan Vogel on the occasion of his 80th birthday. 相似文献
37.
The ability of weeds to form a seed bank is important for their population dynamics and management because it provides a refuge
enabling reinvasion after established target plants have died. However, knowledge of the differential seed behaviour of individual
species over multiple years and varying environmental conditions is surprisingly rare but necessary for effective control
of diverse weed populations. We established a seed burial experiment in alpine habitats differing in management regime (i.e.,
forest, hay meadow and pasture) to determine whether seeds of the unpalatable perennial weeds, Veratrum album (white hellebore) and Gentiana lutea (yellow gentian) were able to delay germination and remain viable over 3 years. Our study shows that both species formed
a short-term persistent seed bank; in the third-year, the soil seed banks of both species were nearly depleted, having declined
to <5% of their original size. Both species had strikingly different germination strategies: G. lutea seeds mainly germinated in their first-year, whilst the majority of V. album seeds germinated in their second-year. The fraction of dormant G. lutea seeds increased with seed age, indicating that seeds remained viable after forgoing germination in the previous year. Habitat-specific
differences in seed germination increased with seed age, with germination fractions being lowest in moist hay meadows. This
suggests that the negative effects of anoxic conditions became more pronounced as seeds aged in hay meadows. Conversely, seed
dormancy was equal among habitats. The absence of a long-term persistent seed bank has important implications for the management
of both nuisance and endangered-plant populations. In the case of V. album and G. lutea, re-colonization of habitats from the seed bank is unlikely after established plants have been removed. 相似文献
38.
Krause Florian Mohebian Kourosh Delpero Manuel Hesse Deike Kühn Ralf Arends Danny Brockmann Gudrun A. 《Mammalian genome》2022,33(3):465-470
Mammalian Genome - The Berlin Fat Mouse Inbred (BFMI) line is a model for juvenile obesity. Previous studies on crosses between BFMI and C57Bl/6N (B6N) have identified a recessive defect causing... 相似文献
39.
E. Hesse A. Best M. Boots A. R. Hall A. Buckling 《Journal of evolutionary biology》2015,28(9):1682-1690
Abiotic environmental heterogeneity can promote the evolution of diverse resource specialists, which in turn may increase the degree of host–parasite specialization. We coevolved Pseudomonas fluorescens and lytic phage ?2 in spatially structured populations, each consisting of two interconnected subpopulations evolving in the same or different nutrient media (homogeneous and heterogeneous environments, respectively). Counter to the normal expectation, host–parasite specialization was significantly lower in heterogeneous compared with homogeneous environments. This result could not be explained by dispersal homogenizing populations, as this would have resulted in the heterogeneous treatments having levels of specialization equal to or greater than that of the homogeneous environments. We argue that selection for costly generalists is greatest when the coevolving species are exposed to diverse environmental conditions and that this can provide an explanation for our results. A simple coevolutionary model of this process suggests that this can be a general mechanism by which environmental heterogeneity can reduce rather than increase host–parasite specialization. 相似文献
40.
Christoph Ott Henrik Martens Imam Hassouna Bárbara Oliveira Christian Erck Maria-Patapia Zafeiriou Ulla-Kaisa Peteri D?rte Hesse Simone Gerhart Bekir Altas Tekla Kolbow Herbert Stadler Hiroshi Kawabe Wolfram-Hubertus Zimmermann Klaus-Armin Nave Walter Schulz-Schaeffer Olaf Jahn Hannelore Ehrenreich 《Molecular medicine (Cambridge, Mass.)》2015,21(1):803-815
Erythropoietin (EPO) exerts potent neuroprotective, neuroregenerative and procognitive functions. However, unequivocal demonstration of erythropoietin receptor (EPOR) expression in brain cells has remained difficult since previously available anti-EPOR antibodies (EPOR-AB) were unspecific. We report here a new, highly specific, polyclonal rabbit EPOR-AB directed against different epitopes in the cytoplasmic tail of human and murine EPOR and its characterization by mass spectrometric analysis of immuno-precipitated endogenous EPOR, Western blotting, immunostaining and flow cytometry. Among others, we applied genetic strategies including overexpression, Lentivirus-mediated conditional knockout of EpoR and tagged proteins, both on cultured cells and tissue sections, as well as intracortical implantation of EPOR-transduced cells to verify specificity. We show examples of EPOR expression in neurons, oligodendroglia, astrocytes and microglia. Employing this new EPOR-AB with double-labeling strategies, we demonstrate membrane expression of EPOR as well as its localization in intracellular compartments such as the Golgi apparatus. Moreover, we show injury-induced expression of EPOR. In mice, a stereotactically applied stab wound to the motor cortex leads to distinct EpoR expression by reactive GFAP-expressing cells in the lesion vicinity. In a patient suffering from epilepsy, neurons and oligodendrocytes of the hippocampus strongly express EPOR. To conclude, this new analytical tool will allow neuroscientists to pinpoint EPOR expression in cells of the nervous system and to better understand its role in healthy conditions, including brain development, as well as under pathological circumstances, such as upregulation upon distress and injury. 相似文献