2,009,831 research outputs found
Heterogeneous and tissue-specific regulation of effector T cell responses by IFN-gamma during Plasmodium berghei ANKA infection.
Get PDFIFN-γ and T cells are both required for the development of experimental cerebral malaria during Plasmodium berghei ANKA infection. Surprisingly, however, the role of IFN-γ in shaping the effector CD4(+) and CD8(+) T cell response during this infection has not been examined in detail. To address this, we have compared the effector T cell responses in wild-type and IFN-γ(-/-) mice during P. berghei ANKA infection. The expansion of splenic CD4(+) and CD8(+) T cells during P. berghei ANKA infection was unaffected by the absence of IFN-γ, but the contraction phase of the T cell response was significantly attenuated. Splenic T cell activation and effector function were essentially normal in IFN-γ(-/-) mice; however, the migration to, and accumulation of, effector CD4(+) and CD8(+) T cells in the lung, liver, and brain was altered in IFN-γ(-/-) mice. Interestingly, activation and accumulation of T cells in various nonlymphoid organs was differently affected by lack of IFN-γ, suggesting that IFN-γ influences T cell effector function to varying levels in different anatomical locations. Importantly, control of splenic T cell numbers during P. berghei ANKA infection depended on active IFN-γ-dependent environmental signals--leading to T cell apoptosis--rather than upon intrinsic alterations in T cell programming. To our knowledge, this is the first study to fully investigate the role of IFN-γ in modulating T cell function during P. berghei ANKA infection and reveals that IFN-γ is required for efficient contraction of the pool of activated T cells
Bacterial production of poly-γ-glutamic acid and evaluation of its effect on the viability of probiotic microorganisms
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By Aditya Bhat, MScPoly-γ-glutamic acid (γ-PGA) is a naturally occurring biopolymer made up of repeating units of glutamic acid and can be potentially used for multiple applications. This study compared the production of γ-PGA by eight bacteria (B. subtilis 23856, B. subtilis 23857, B. subtilis 23858 B. subtilis 23859, B. subtilis natto, B. licheniformis 1525, B. licheniformis 6816 and B. licheniformis 9945a) in GS and E media. B. subtilis natto and B. licheniformis 9945a have been investigated extensively for γ-PGA production, however, the remaining six have not previously been used. Using the eight bacteria, yields of up to 22.3 g/l were achieved in shake flasks. On characterization, it was observed that γ-PGA with different properties (crystallinity, acid/salt form and molecular weights ranging from 3,000 Da to 871,000 Da) was produced. Production of γ-PGA by B. subtilis natto in GS medium was scaled up using a fermenter and was tested for novel probiotic applications. The survival of probiotics during freeze drying, storage and ingestion was improved by combining them with a γ-PGA matrix. For L. paracasei, 10% γ-PGA protected the cells significantly better (P 0.05) to 10% sucrose. This study also demonstrated the potential use of a non-dairy foodstuff (orange juice) for delivery of probiotics. Two Bifidobacteria strains protected with γ-PGA survived significantly better (P < 0.05) in orange juice for 39 days, with a log reduction in viability of less than 2.99 CFU/ml, when compared to unprotected cells, which showed complete loss in viability by day 20. In addition, γ-PGA protection improved survival of Bifidobacteria in a solution mimicking the environment of the stomach. γ-PGA-protected Bifidobacteria showed little (< 0.47 log CFU/ml) or no loss in viability when stored in simulated gastric juice (pH 2.0) for four hours, whereas unprotected cells died within two hours
Evidence for the decay X(3872)→ψ(2S)γ
Get PDFEvidence for the decay mode X(3872)→ψ(2S)γ in B+→X(3872)K+ decays is found with a significance of 4.4 standard deviations. The analysis is based on a data sample of proton–proton collisions, corresponding to an integrated luminosity of 3 fb−1, collected with the LHCb detector, at centre-of-mass energies of 7 and 8 TeV. The ratio of the branching fraction of the X(3872)→ψ(2S)γ decay to that of the X(3872)→J/ψγ decay is measured to be
where the first uncertainty is statistical and the second is systematic. The measured value does not support a pure molecular interpretation of the X(3872) state
"Ηπειρωτική ψυχή" : Ετήσιον εικονογραφημένον λεύκωμα / Σ. Γ. Παππά, Κ. Μ. Κιουρή, Α. Γ. Νικολαΐδη.
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Διπλωματία και πόλεμος : Γεώργιος Ζαχ. Σκουλούδης, Εμμανουήλ Παχλάς: δύο Ρεθεμνιώτικες μορφές στο σταυροδρόμι του Αρκαδίου / Δημήτριος Γ. Στεργίου, Χρήστος Γ. Ζαχαράκις.
No full textHarvest at Palatitsia village (Imathia)
No full text1 φωτογραφία : ασπρόμ. ; 15Χ10,5εκ.Θέρισμα σιταριού στα Παλατίτσια Ημαθίας. Σκληρή και κοπιαστική δουλειά. Η φωτογραφία είναι του 1897, τραβηγμένη από το Γ. Βαφειάδη. (Ακριβόπουλος Μ., Λεύκωμα, 1986: σ. 88)
Μελέτη περί της εν Ελλάδι μεταναστεύσεως αναφορικώς και εκ της επαρχίας Μεγαλοπόλεως / Νικολάου Γ. Πιεροπούλου (Παπαϊωάννου).
No full textThe haunt of Palatitsia village
No full text1 φωτογραφία : ασπρόμ. ; 15Χ10,5εκ.Κονάκι στα Παλατίτσια το 1897 φωτογραφημένο από το Γ. Βαφειάδη
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