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101.
Aleksandar Zocevic Fabien Vorimore Nadia Vicari Julien Gasparini Lisa Jacquin Konrad Sachse Simone Magnino Karine Laroucau 《PloS one》2013,8(3)
Recent evidence of the occurrence of atypical Chlamydiaceae strains in pigeons, different from the established Chlamydiaceae, requires the development of a specific and rapid detection tool to investigate their prevalence and significance. Here is described a new real-time PCR assay that allows specific detection of atypical Chlamydiaceae from pigeons. The assay has been used to assess the dissemination of these strains in field samples collected from Parisian pigeon populations in 2009. The results suggest a limited dissemination compared to the usually higher prevalence of Chlamydia psittaci that is the main species associated with avian chlamydiosis. 相似文献
102.
Sarah Kutscher Claudia J. Dembek Simone Deckert Carolina Russo Nina K?rber Johannes R. Bogner Fabian Geisler Andreas Umgelter Michael Neuenhahn Julia Albrecht Antonio Cosma Ulrike Protzer Tanja Bauer 《PloS one》2013,8(10)
Polyfunctional CD4 or CD8 T cells are proposed to represent a correlate of immune control for persistent viruses as well as for vaccine mediated protection against infection. A well-suited methodology to study complex functional phenotypes of antiviral T cells is the combined staining of intracellular cytokines and phenotypic marker expression using polychromatic flow cytometry. In this study we analyzed the effect of an overnight resting period at 37°C on the quantity and functionality of HIV-1, EBV, CMV, HBV and HCV specific CD4 and CD8 T-cell responses in a cohort of 21 individuals. We quantified total antigen specific T cells by multimer staining and used 10-color intracellular cytokine staining (ICS) to determine IFNγ, TNFα, IL2 and MIP1β production. After an overnight resting significantly higher numbers of functionally active T cells were detectable by ICS for all tested antigen specificities, whereas the total number of antigen specific T cells determined by multimer staining remained unchanged. Overnight resting shifted the quality of T-cell responses towards polyfunctionality and increased antigen sensitivity of T cells. Our data suggest that the observed effect is mediated by T cells rather than by antigen presenting cells. We conclude that overnight resting of PBMC prior to ex vivo analysis of antiviral T-cell responses represents an efficient method to increase sensitivity of ICS-based methods and has a prominent impact on the functional phenotype of T cells. 相似文献
103.
Seveso Davide Arrigoni Roberto Montano Simone Maggioni Davide Orlandi Ivan Berumen Michael L. Galli Paolo Vai Marina 《Coral reefs (Online)》2020,39(1):85-98
Coral Reefs - Coral bleaching represents the most serious threat to contemporary coral reefs. In response, focus is being laid on understanding the cellular processes involved in the response of... 相似文献
104.
Robert L. Pitman John W. Durban Trevor Joyce Holly Fearnbach Simone Panigada Giancarlo Lauriano 《Marine Mammal Science》2020,36(2):565-594
Long-distance migration in whales has historically been described as an annual, round-trip movement between high-latitude, summer feeding grounds, and low-latitude, winter breeding areas, but there is no consensus about why whales travel to the tropics to breed. Between January 2009 and February 2016, we satellite-tagged 62 antarctic killer whales (Orcinus orca) of four different ecotypes, of which at least three made short-term (6–8 weeks), long-distance (maximum 11,000 km, round trip), essentially nonstop, migrations to warm waters (SST 20°C–24°C), and back. We previously suggested that antarctic killer whales could conserve body heat in subfreezing (to −1.9°C) waters by reducing blood flow to their skin, but that this might preclude normal (i.e., continuous) epidermal molt, and necessitate periodic trips to warm waters for routine skin maintenance (“skin molt migration,” SMM). In contrast to the century-old “feeding/breeding” migration paradigm, but consistent with a “feeding/molting” hypothesis, the current study provides additional evidence that deferred skin molt could be the main driver of long-distance migration for antarctic killer whales. Furthermore, we argue that for all whales that forage in polar latitudes and migrate to tropical waters, SMM might also allow them to exploit rich prey resources in a physiologically challenging environment and maintain healthy skin. 相似文献
105.
Deborah C. Holt Stewart T. G. Burgess Simone L. Reynolds Wajahat Mahmood Katja Fischer 《Cell and tissue research》2013,351(2):339-352
Among arthropod pests, mites are responsible for considerable damage to crops, humans and other animals. However, detailed physiological data on these organisms remain sparse, mainly because of their small size but possibly also because of their extreme diversity. Focusing on intestinal proteases, we draw together information from three distinct mite species that all feed on skin but have separately adapted to a free-living, a strictly ecto-parasitic and a parasitic lifestyle. A wide range of studies involving immunohistology, molecular biology, X-ray crystallography and enzyme biochemistry of mite gut proteases suggests that these creatures have diverged considerably as house dust mites, sheep scab mites and scabies mites. Each species has evolved a particular variation of a presumably ancestral repertoire of digestive enzymes that have become specifically adapted to their individual environmental requirements. 相似文献
106.
107.
Christoph Domschke Yingzi Ge Isa Bernhardt Sarah Schott Sophia Keim Simone Juenger Mariana Bucur Luisa Mayer Maria Blumenstein Joachim Rom Joerg Heil Christof Sohn Andreas Schneeweiss Philipp Beckhove Florian Schuetz 《Cancer immunology, immunotherapy : CII》2013,62(6):1053-1060
Background
The bone marrow (BM) of breast cancer patients harbors tumor-reactive memory T cells (TCs) with therapeutic potential. We recently described the immunologic effects of adoptive transfer of ex vivo restimulated tumor-reactive memory TCs from the BM of 12 metastasized breast cancer patients in a clinical phase-I study. In this trial, adoptive T cell transfer resulted in the occurrence of circulating tumor antigen-reactive type-1 TCs. We here describe the long-term clinical outcome and its correlation with tumor-specific cellular immune response in 16 metastasized breast cancer patients, including 12 included in the original study.Methods
Sixteen metastatic breast cancer patients with preexisting tumor-reactive BM memory TCs were included into the study. The study protocol involved one transfusion of TCs which were reactivated in vitro with autologous dendritic cells pulsed with lysates of MCF-7 breast cancer cells as source of tumor antigens. The presence of tumor-reactive memory TCs was analyzed by IFN-γ ELISpot assays.Results
Tumor-reactive memory TCs in the peripheral blood were induced de novo in 7/16 patients (44 %) after adoptive TC transfer. These patients were considered immunologic responders to the therapy. Positive adoptive immunotherapy (ADI) response was observed significantly more often in patients without bone metastases (p = 0.0051), in patients with high levels of tumor-reactive BM TCs prior to therapy (p = 0.036) and correlated significantly with the estimated numbers of transferred tumor-reactive TCs (p = 0.0021). After the treatment, we observed an overall median survival of 33.8 months in the total cohort with three patients alive at last follow-up and more than 7 years after ADI. Numbers of transferred tumor-reactive TCs correlated significantly with the overall survival of patients (p = 0.017). Patients with an immunologic response to ADI in the peripheral blood had a significantly longer median survival than nonresponders (median survival 58.6 vs. 13.6 months; p = 0.009).Conclusion
In metastasized breast cancer patients, adoptive transfer of BM TCs can induce the presence of tumor antigen-reactive type-1 TCs in the peripheral blood. Patients with immunologic response after ADI show a significantly longer overall survival. Patients with bone metastases significantly less frequently respond to the treatment and, therefore, might not be optimal candidates for ADI. Although the present study does not yet prove the therapeutic effect of ADI, these findings shed light on the relation between immune response and cancer prognosis and suggest that transfer of reactivated BM TCs might bear therapeutic potential. 相似文献108.
109.
Alfonso De Simone Francesca Stanzione Daniela Marasco 《Journal of biomolecular structure & dynamics》2013,31(5):441-452
Human prion diseases are neurodegenerative disorders associated to the misfolding of the prion protein (PrP). Common features of prion disorders are the fibrillar amyloid deposits and the formation of prefibrillar oligomeric species also suggested as the origin of cytotoxicity associated with diseases. Although the process of PrP misfolding has been extensively investigated, many crucial aspects of this process remain unclear. We have here carried out a molecular dynamics study to evaluate the intrinsic dynamics of PrP β-sheet, a region that is believed to play a crucial role in prion aggregation. Moreover, as this region mediates protein association in dimeric assemblies frequently observed in prion crystallographic investigations, we also analyzed the dynamics of these intermolecular interactions. The extensive sampling of replica exchange shows that the native antiparallel β-structure of the prion is endowed with a remarkable stability. Therefore, upon unfolding, the persistence of a structured β-region may seed molecular association and influence the subsequent phases of the aggregation process. The analysis of the four-stranded β-sheet detected in the dimeric assemblies of PrP shows a tendency of this region to form dynamical structured states. The impact on the β-sheet structure and dynamics of disease associated point mutations has also been evaluated. 相似文献
110.