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111.
Christian Milani Arancha Hevia Elena Foroni Sabrina Duranti Francesca Turroni Gabriele Andrea Lugli Borja Sanchez Rebeca Martín Miguel Gueimonde Douwe van Sinderen Abelardo Margolles Marco Ventura 《PloS one》2013,8(7)
Assessing the distribution of 16S rRNA gene sequences within a biological sample represents the current state-of-the-art for determination of human gut microbiota composition. Advances in dissecting the microbial biodiversity of this ecosystem have very much been dependent on the development of novel high-throughput DNA sequencing technologies, like the Ion Torrent. However, the precise representation of this bacterial community may be affected by the protocols used for DNA extraction as well as by the PCR primers employed in the amplification reaction. Here, we describe an optimized protocol for 16S rRNA gene-based profiling of the fecal microbiota. 相似文献
112.
Ielham Hadad Alex Veithen Jean–Yves Springael Panagiota A. Sotiropoulou Agnès Mendes Da Costa Fran?oise Miot Robert Naeije Xavier De Deken Kathleen Mc Entee 《PloS one》2013,8(2)
Stroma cell-derived factor-1α (SDF-1α) is a cardioprotective chemokine, acting through its G-protein coupled receptor CXCR4. In experimental acute myocardial infarction, administration of SDF-1α induces an early improvement of systolic function which is difficult to explain solely by an anti-apoptotic and angiogenic effect. We wondered whether SDF-1α signaling might have direct effects on calcium transients and beating frequency.Primary rat neonatal cardiomyocytes were culture-expanded and characterized by immunofluorescence staining. Calcium sparks were studied by fluorescence microscopy after calcium loading with the Fluo-4 acetoxymethyl ester sensor. The cardiomyocyte enriched cellular suspension expressed troponin I and CXCR4 but was vimentin negative. Addition of SDF-1α in the medium increased cytoplasmic calcium release. The calcium response was completely abolished by using a neutralizing anti-CXCR4 antibody and partially suppressed and delayed by preincubation with an inositol triphosphate receptor (IP3R) blocker, but not with a ryanodine receptor (RyR) antagonist. Calcium fluxes induced by caffeine, a RyR agonist, were decreased by an IP3R blocker. Treatment with forskolin or SDF-1α increased cardiomyocyte beating frequency and their effects were additive. In vivo, treatment with SDF-1α increased left ventricular dP/dtmax.These results suggest that in rat neonatal cardiomyocytes, the SDF-1α/CXCR4 signaling increases calcium transients in an IP3-gated fashion leading to a positive chronotropic and inotropic effect. 相似文献
113.
Nina Stemmer Elena Strekalova Nevena Djogo Frank Pl?ger Gabriele Loers David Lutz Friedrich Buck Marek Michalak Melitta Schachner Ralf Kleene 《PloS one》2013,8(4)
Dysregulation of the proteolytic processing of amyloid precursor protein by γ-secretase and the ensuing generation of amyloid-β is associated with the pathogenesis of Alzheimer''s disease. Thus, the identification of amyloid precursor protein binding proteins involved in regulating processing of amyloid precursor protein by the γ-secretase complex is essential for understanding the mechanisms underlying the molecular pathology of the disease. We identified calreticulin as novel amyloid precursor protein interaction partner that binds to the γ-secretase cleavage site within amyloid precursor protein and showed that this Ca2+- and N-glycan-independent interaction is mediated by amino acids 330–344 in the C-terminal C-domain of calreticulin. Co-immunoprecipitation confirmed that calreticulin is not only associated with amyloid precursor protein but also with the γ-secretase complex members presenilin and nicastrin. Calreticulin was detected at the cell surface by surface biotinylation of cells overexpressing amyloid precursor protein and was co-localized by immunostaining with amyloid precursor protein and presenilin at the cell surface of hippocampal neurons. The P-domain of calreticulin located between the N-terminal N-domain and the C-domain interacts with presenilin, the catalytic subunit of the γ-secretase complex. The P- and C-domains also interact with nicastrin, another functionally important subunit of this complex. Transfection of amyloid precursor protein overexpressing cells with full-length calreticulin leads to a decrease in amyloid-β42 levels in culture supernatants, while transfection with the P-domain increases amyloid-β40 levels. Similarly, application of the recombinant P- or C-domains and of a synthetic calreticulin peptide comprising amino acid 330–344 to amyloid precursor protein overexpressing cells result in elevated amyloid-β40 and amyloid-β42 levels, respectively. These findings indicate that the interaction of calreticulin with amyloid precursor protein and the γ-secretase complex regulates the proteolytic processing of amyloid precursor protein by the γ-secretase complex, pointing to calreticulin as a potential target for therapy in Alzheimer''s disease. 相似文献
114.
Stefania Parlato Roberto Bruni Paola Fragapane Debora Salerno Cinzia Marcantonio Paola Borghi Paola Tataseo Anna Rita Ciccaglione Carlo Presutti Giulia Romagnoli Irene Bozzoni Filippo Belardelli Lucia Gabriele 《PloS one》2013,8(8)
Type I interferon (IFN-I) have emerged as crucial mediators of cellular signals controlling DC differentiation and function. Human DC differentiated from monocytes in the presence of IFN-α (IFN-α DC) show a partially mature phenotype and a special capability of stimulating CD4+ T cell and cross-priming CD8+ T cells. Likewise, plasmacytoid DC (pDC) are blood DC highly specialized in the production of IFN-α in response to viruses and other danger signals, whose functional features may be shaped by IFN-I. Here, we investigated the molecular mechanisms stimulated by IFN-α in driving human monocyte-derived DC differentiation and performed parallel studies on peripheral unstimulated and IFN-α-treated pDC. A specific miRNA signature was induced in IFN-α DC and selected miRNAs, among which miR-23a and miR-125b, proved to be negatively associated with up-modulation of Blimp-1 occurring during IFN-α-driven DC differentiation. Of note, monocyte-derived IFN-α DC and in vitro IFN-α-treated pDC shared a restricted pattern of miRNAs regulating Blimp-1 expression as well as some similar phenotypic, molecular and functional hallmarks, supporting the existence of a potential relationship between these DC populations. On the whole, these data uncover a new role of Blimp-1 in human DC differentiation driven by IFN-α and identify Blimp-1 as an IFN-α-mediated key regulator potentially accounting for shared functional features between IFN-α DC and pDC. 相似文献
115.
Michael Edlinger Nicole Concin Hans Concin Gabriele Nagel Hanno Ulmer Georg Göbel 《Cancer epidemiology》2013,37(2):156-161
Background: Lifestyle seems to play an important role in endometrial cancer mortality, but it remains unclear which biomarkers are involved. The aim of this study was to assess the extent of the association between lifestyle-related biomarkers and the survival of endometrial cancer patients. Methods: A sub-cohort of 242 endometrial cancer patients, from a population-based study of the more than 90,000 female participants of the Vorarlberg Health Monitoring and Promotion Programme, was followed for a median duration of twelve years. Besides age, tumour staging, and histology, also pre-diagnostic levels of body mass index, blood pressure, triglycerides, total cholesterol, glucose, gamma-glutamyltransferase (GGT), and serum uric acid were analysed in Cox proportional hazards regression models to estimate multivariate mortality risks. Results: During follow-up 89 deaths occurred of which 49 were cancer-related. Survival was associated with age, tumour stage, and histology. Of the biomarkers, log10-transformed GGT showed a large effect on cancer-related mortality (HR = 3.35, 95% CI 1.12–10.03), whereas the other parameters did not appear with significant effects after adjustment for the other factors. Conclusion: Elevated level of GGT, a lifestyle-related marker, was associated with poor survival among endometrial cancer patients. 相似文献
116.
Bruno Rivas-Santiago Julio E. Casta?eda-Delgado Cesar E. Rivas Santiago Matt Waldbrook Irma González-Curiel Juan C. León–Contreras Jose Antonio Enciso-Moreno Victor del Villar Jazmin Mendez-Ramos Robert E. W. Hancock Rogelio Hernandez-Pando 《PloS one》2013,8(3)
Tuberculosis is an ongoing threat to global health, especially with the emergence of multi drug-resistant (MDR) and extremely drug-resistant strains that are motivating the search for new treatment strategies. One potential strategy is immunotherapy using Innate Defence Regulator (IDR) peptides that selectively modulate innate immunity, enhancing chemokine induction and cell recruitment while suppressing potentially harmful inflammatory responses. IDR peptides possess only modest antimicrobial activity but have profound immunomodulatory functions that appear to be influential in resolving animal model infections. The IDR peptides HH2, 1018 and 1002 were tested for their activity against two M. tuberculosis strains, one drug-sensitive and the other MDR in both in vitro and in vivo models. All peptides showed no cytotoxic activity and only modest direct antimicrobial activity versus M. tuberculosis (MIC of 15–30 µg/ml). Nevertheless peptides HH2 and 1018 reduced bacillary loads in animal models with both the virulent drug susceptible H37Rv strain and an MDR isolate and, especially 1018 led to a considerable reduction in lung inflammation as revealed by decreased pneumonia. These results indicate that IDR peptides have potential as a novel immunotherapy against TB. 相似文献
117.
118.
Alfredo Vizzini Angela Lantieri Gianfranco Medardi Enrico Ercole Gabriele Cacialli 《Mycological Progress》2016,15(8):883-901
This study was focused on species of Peziza belonging to the “P. ammophila” complex, using both morphological and molecular approaches. Molecular and morphological analyses showed that several taxa are hidden under the name “ammophila” and, as a consequence, two additional species and one form are established: P. hellenica sp. nov., P. oceanica sp. nov. and P. ammophila f. megaspora f. nov. On the basis of the data that we have, these taxa seem to be related to some geographical areas; P. ammophila appears to be prevalent in northern, central and southern Europe, its f. megaspora is distributed in France and in the Netherlands, P. hellenica comes from Greece and P. oceanica from New Zealand. A cryptic species, not yet circumscribed satisfactorily, is described as P. deceptiva ad int. Moreover, the problem concerning the identification of P. ammophila is raised, the species is epitypified with a sequenced collection from Sicily (Italy) and a key to the species of the complex is provided. 相似文献
119.
Association between a school‐based intervention and adiposity outcomes in adolescents: The Italian “EAT” project
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120.
Sheila N. Balinda Pascale Ondoa Ekwaro A. Obuku Aletta Kliphuis Isaac Egau Michelle Bronze Lordwin Kasambula Rob Schuurman Nicole Spieker Tobias F. Rinke de Wit Cissy Kityo ART–A consortium 《PloS one》2016,11(1)