Prolonged Graft Survival in Older Recipient Mice Is Determined by Impaired Effector T-Cell but Intact Regulatory T-Cell Responses

Elderly organ transplant recipients represent a fast growing segment of patients on the waiting list. We examined age-dependent CD4+ T-cell functions in a wild-type (WT) and a transgenic mouse transplant model and analyzed the suppressive function of old regulatory T-cells. We found that splenocytes of naïve old B6 mice contained significantly higher frequencies of T-cells with an effector/memory phenotype (CD4+CD44highCD62Llow). However, in-vitro proliferation (MLR) and IFNγ-production (ELISPOT) were markedly reduced with increasing age. Likewise, skin graft rejection was significantly delayed in older recipients and fewer graft infiltrating CD4+T-cells were observed. Old CD4+ T-cells demonstrated a significant impaired responsiveness as indicated by diminished proliferation and activation. In contrast, old alloantigen-specific CD4+CD25+FoxP3+ T-cells demonstrated a dose-dependent well-preserved suppressor function. Next, we examined characteristics of 18-month old alloreactive T-cells in a transgenic adoptive transfer model. Adoptively transferred old T-cells proliferated significantly less in response to antigen. Skin graft rejection was significantly delayed in older recipients, and graft infiltrating cells were reduced. In summary, advanced recipient age was associated with delayed acute rejection and impaired CD4+ T-cell function and proliferation while CD4+CD25+FoxP3+ T-cells (Tregs) showed a well-preserved function

Eine kleine Einfuehrung ueber die Balancierung in der Ausgleichsrechnung

Available from TIB Hannover: RR 5094(46) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Eine kleine Einfuehrung ueber die Balancierung in der Ausgleichsrechnung

Available from TIB Hannover: RR 5094(46) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Ueber balancierte Beobachtungen im Modell der bedingten Beobachtungen am Beispiel einer ausgleichenden Geraden

Available from TIB Hannover: RR 5094(37) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Detection of handwriting forgery made with erasable pens using desorption electrospray mass spectrometry imaging

Documents with handwritten portions are often susceptible to adulteration, forgery, and addition of entries, raising a problem of social concern. In this study, DESI ionization with imaging capabilities is applied to identify fraud in handwritten documents made using erasable pens of the chemical method of erasing (other than the usual physical methods). A fraud procedure was simulated in which an original entry made in white office paper was erased and replaced with a new one. The areas were directly analyzed using a DESI-MSI ion source coupled to a Q-Extractive mass spectrometer. Chemical images were obtained mapping the intensity of selected ions, spelling out each part of the fraud process as irrefutable evidence of its occurrence. Thus, the potential application of DESI-MSI in detecting fraud in suspect documents is demonstrated as a useful, simple, and fast alternative for the traditional techniques employed in these situations31410001003CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão temnão temnão temnão te

Oxygen in GaAs and its relation to the EL3 defect investigated by TSC and PICTS

Thermally stimulated current (TSC) and photo induced current transient spectroscopy (PICTS) were used to investigate deep traps in oxygen-rich medium resistivity GaAs. We observed an abnormal behaviour of the TSC signal at a temperature of about 200 K, where the TSC current is lower than the dark current. This results in a negative peak occurring in the temperature range where the signal of the well known EL3 defect in undoped semi-insulating GaAs is present. For verification, comparative PICTS-measurements were performed, which exhibit the same negative peak at similar temperatures. The activation energy for this negative peak was determined to be ~ 0.6 eV (TSC). This is in good agreement with published values for the EL3 ranging from 0.56 to 0.68 eV. Furthermore, we illustrate that the depth of the peak increases with increasing oxygen content. Our results support the assumption, that oxygen on an arsenic site – the so called off centre oxygen oc-OAs – should be the origin of the EL3

Introducing the natural generalization of partial redundancies within linear Gauss-Markov-Parameter estimation

SIGLEAvailable from TIB Hannover: RR 5094(65) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman