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Serum growth-promoting activity measured as [3H]thymidine incorporation into human activated lymphocytes and serum transferrin levels in newborns and mothers
No full textNatural cytotoxicity in the neonate: high levels of lymphokine activated killer (LAK) activity.
Full text linkIn 28 healthy full-term newborns the percentage of circulating cells expressing the Leu7 antigen, the marker of natural killer (NK) cells, was significantly lower than in healthy adults. However, newborns and adults did not differ with regard to the percentage of cells reacting with the Leulla, Leullc and TEC NK-1, monoclonal antibodies directed against the IgG Fc receptor of killer cells. Spontaneous NK activity of neonatal cells was profoundly reduced compared to the adult. In contrast, antibody dependent cellular cytotoxicity and NK-like activity generated in mixed lymphocyte cultures were similar in the two groups and lymphokine-activated killer cell (LAK) activity was high in the neonate. Natural killing is thought to play an important role in antiviral immunity since the neonate has a deficient capacity to deal with viral infections. Consequently, the present data indicate either that spontaneous NK is the most informative in vitro measure of newborn natural cytotoxicity in vivo, or, alternatively, that natural killing is not as important in antiviral immunity as previously suggeste
In vivo activated cord blood lymphocytes express high affinity interleukin-2 receptor: evaluation of their responsiveness to in vitro stimulation with recombinant interleukin-2.
No full textWe report the phenotypical and functional characterization of a cord blood mononuclear lymphocyte subset (CBMC) which expresses the p55 chain of interleukin-2 receptor (IL-2R, CD25). The great majority of CD25-positive CBMC are activated CD3-positive T lymphocytes in that most of them are HLA-DR-positive, coexpress both CD4 and CD8 antigens and at least a part of them display high affinity IL-2R. In keeping with the expression of both chains of IL-2R (p55 and p75), enriched CD25-positive CBMC are able to display strong IL-2-induced proliferation and lymphokine-activated killing activity. The percentage of CD25-positive cells is higher in cord blood than in adult peripheral blood and their presence could be peculiarly important in the neonatal period, when specific T-cell-mediated immune responses are still on their way to full maturation
Expression of CD45R0 antigen on the surface of resting and activated neonatal T lymphocyte subsets.
No full textExpression of CD45R0 antigen has been evaluated on the surface of T lymphocyte subsets obtained from cord blood and on peripheral blood lymphocytes (PBL) from both term and preterm neonates. In some experiments, expression of the same antigen has also been evaluated after in vitro activation of cord blood lymphocytes (CBL) with phytohemagglutinin (PHA) or in mixed lymphocyte culture. The CD45R0 molecule was found to be present on a significantly lower percentage of CD3+, CD4+ and CD8+ CBL as compared with the same subsets evaluated in adult individuals. Moreover, at variance with adult PBL, the great majority of CBL displayed a low level of fluorescence when stained with UCHL1 (CD45R0-specific monoclonal antibody), and both PHA and allogeneic stimuli were able to strongly increase the expression of the CD45R0 molecule on CBL. The percentage of CD45R0+ PBL obtained from both term and preterm neonates on the 1st day of life was comparable to that of CBL, however the expression of this molecule increases remarkably within a few days in the majority of term neonates, while it seems to take more time for the antigen to be fully expressed in preterm infants
Colostral T lymphocytes detected by intracytoplasmic and membrane markers.
No full textColostral lymphocytes were studied using two established T-cell markers: intracytoplasmic alpha-naphtyl-acetate esterase (ANAE) staining and membrane receptors for sheep erythrocytes (E rosettes). ANAE staining allowed counting and identification of T-cell subsets independently of the status of membrane structures and receptors frequently altered in colostral cells. The fact that a sizeable number of colostral lymphocytes had the same phenotype as the majority of mature circulating peripheral blood lymphocytes supports the hypothesis that colostral lymphocytes may play a role in protecting neonates against infections, in transferring immune information to the newborn, or in modulating the immune response via release of soluble factors. A considerable percentage of colostral T lymphocytes are ANAE-negative. This phenotype is similar to that observed among thymocytes
Age-related variation in growth-promoting activity human plasma measured in human lymphocytes
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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