Migration patterns of dendritic cells in the mouse. Traffic from the blood, and T cell-dependent and -independent entry to lymphoid tissues.

Dendritic cells (DC) are critical accessory cells for primary immune responses and they may be important stimulators of transplantation reactions, but little is known of their traffic into the tissues. We have studied the migration of purified splenic DC and T lymphocytes, labeled with 111Indium-tropolone, in syngeneic and allogeneic mice. First we demonstrate that DC can migrate from the blood into some lymphoid and nonlymphoid tissues. Immediately after intravenous administration, radio-labeled DC were sequestered in the lungs, but they actively migrated into the liver and spleen and reached equilibrium levels between 3 and 24 h after transfer. At least half of the radiolabel accumulated in the liver, but the spleen was the principal site of DC localization in terms of specific activity (radiolabel per weight of tissue). DC were unable to enter Peyer's patches, or mesenteric and other peripheral lymph nodes from the bloodstream. This was also true in splenectomized recipients, where the otherwise spleen-seeking DC were quantitatively diverted to the liver. In contrast, T cells homed readily to the spleen and lymph nodes of normal mice and increased numbers were present in these tissues in splenectomized mice. Thus, unlike T cells, DC cannot recirculate from blood to lymph via the nodes. We then show that migration of DC from the blood into the spleen is dependent on the presence of T cells: DC did not enter the spleens of nude mice, but when they were reconstituted with T cells the numbers entering the spleen resembled those in euthymic mice. In nude mice, as in splenectomized recipients, the DC that would normally enter the spleen were quantitatively diverted to the liver. These findings suggest that there is a spleen-liver equilibrium for DC, that may be akin to that existing between spleen and lymph node for T cells. Finally, we followed the traffic of radiolabeled DC via the afferent lymphatics after subcutaneous footpad inoculation. DC accumulated in the popliteal nodes but did not migrate further to the inguinal nodes. There was no difference between euthymic and nude mice, showing that unlike traffic to the spleen, this route probably does not require T cells. These migration patterns were not affected by major histocompatibility barriers, and were only seen with viable, but not glutaraldehyde-fixed, DC.(ABSTRACT TRUNCATED AT 400 WORDS

Fibronectin in immune responses in organ transplant recipients.

The immune response to an organ allograft involves perpetuation of T cell infiltration and activation. Advances in understanding the mechanisms of T cell activation have placed particular emphasis on the interactions between the T-cell receptor and antigen presenting cells, with little reference to the fact that in vivo activation occurs in the physical context of extracellular matrix proteins (ECM). Indeed, the possibility that ECM proteins may have a determining role in lymphocyte adhesion and tissue localization and function is now becoming more appreciated in view of growing evidence indicating that integrins and other T cell antigens bind ECM components, with some of these components exerting synergistic effects on T-cell activation. This review focuses on the importance of interactions between lymphocytes and fibronectin, a prominent ECM component, for cell migration and function in organ allograft recipients. It explores novel therapeutic approaches based on the assumption that fibronectin represents an active element in the process of T cell activation in the immune cascade triggered by organ transplantation

Asexual propagation of blackbrush (Coleogyne ramosissima Torr.)

1990 Summer.Covers not scanned.Includes bibliographical references.Mining disturbances in Canyonlands National Park occur, in part, in monotypic stands of blackbrush (Coleogyne ramosissima Torr.). Blackbrush does not readily reseed itself following disturbance, therefore, stem cuttings and mound layering were evaluated as methods for asexual propagation as a means of providing plants to be used in a revegetation program. Rooted cuttings were planted to evaluate their use in revegetation. Rooting of stem cuttings was evaluated using talc, 0.3% (w/v) indole-3-butyric acid (IBA), 0.8% (w/v) IBA, and Rootone, a commercially available rooting hormone mixture. Treatments were applied to cuttings collected from new, one-year-old, and older wood (2+ years) at three separate dates. Propagation by stem cutting proved successful with highest rooting percentages achieved using current year's growth with application of supplemental rooting hormone. Differences between hormone treatments were insignificant. However, differences were found in comparisons between hormone treatments and a talc control. Mound layering was investigated with 20 plants at each of three sites and involved removal of all growth over 2.5 cm above ground level. Supplemental water was applied to half the plants for the duration of the study. Plants were buried to one-half of the height of new growth on a monthly basis. Plants responded to the treatment with a flush of growth but did not root. Thirty-eight cuttings rooted the prior year were planted in spring 1989 in an abandoned roadbed to evaluate field establishment. Treatments included application of supplemental water at two week intervals. Results were inconclusive

Migration patterns of dendritic cells in the mouse. Homing to T cell-dependent areas of spleen, and binding within marginal zone.

Using quantitative techniques we have shown elsewhere that dendritic cells (DC) migrate from blood into the spleen, under the control of T cells. Here we traced the localization of DC within the spleen and sought to explain the means by which they entered. DC were labeled with a fluorochrome, Hoescht 33342, and injected intravenously. Spleens were removed 3 or 24 h later and DC were visualized within particular areas that were defined by mAbs and FITC anti-Igs. At 3 h most DC were in the red pulp, whereas by 24 h the majority had homed to T-dependent areas of the white pulp and may have become interdigitating cells. Lymphoid DC, isolated from spleen and perhaps normally present in blood, may thus be a migratory stage distinct from the relatively fixed interdigitating cells. We also developed a frozen section assay to investigate the interaction of DC with various lymphoid elements. When DC were incubated on sections of spleen, at 37 degrees C but not at 4 degrees C they attached specifically within the marginal zone and did not bind to T areas; in contrast, macrophages attached only to red pulp and T cells did not bind specifically. However, DC did not bind to sections of mesenteric lymph node, whereas T cells localized in particular regions at 4 degrees C but not at 37 degrees C, probably the high endothelial venules. DC may thus express "homing receptors," similar to those of T cells, for certain endothelia. We propose that T cells can modify the vascular endothelium in certain areas to allow egress of DC from the bloodstream

Webdocumentário: uma linguagem criativa na formação dos estudantes de comunicação

Os avanços na tecnologia digital e o advento da internet possibilitaram o surgimento de narrativas inovadoras nos meios de comunicação e de novos gêneros e subgêneros dos discursos midiáticos como as narrativas jornalísticas multimídia e os webdocumentários. Estes formatos e conteúdos inventivos são exemplos de transformações nos usos de linguagens e suportes nos veículos midiáticos marcados por uma pluralidade de vozes, pela interatividade, pela diversidade de combinação de códigos audiovisuais e de interconexões entre textos verbais e não verbais e por uma expressiva capacidade de armazenamento de dados. Essas narrativas tendem a não preservar apenas os valores hegemônicos, contribuindo para representações mais democráticas de acontecimentos e fenômenos culturais. Este trabalho consiste em uma análise das principais características do webdocumentário. Propõe uma reflexão crítica sobre a importância do aprendizado dessa linguagem criativa, original e complexa na formação dos alunos de Comunicação, por meio de um estudo empírico do webdocumentário (Des)Ocupações, produzido pelo TJ UFRJ (http://www.tj.ufrj.br/), laboratório da ECO-UFRJ que participo desde abril de 2012

Perceived Corruption in Ukraine: A National Analysis Using Individual Level Data from 2012-2014

This study examines the relationship of perceived corruption in Ukraine and the factors that influence that perception. In particular, this paper investigates the idea that an influential Russian presence affects the perception of governmental corruption amongst Ukrainian business owners and managers

PACAP neuropeptide promotes Hepatocellular Protection via CREB-KLF4 dependent autophagy in mouse liver Ischemia Reperfusion Injury.

Organ ischemia reperfusion injury (IRI), associated with acute hepatocyte death, remains an unresolved problem in clinical orthotopic liver transplantation (OLT). Autophagy, an intracellular self-digesting progress, is responsible for cell reprograming required to regain post-stress homeostasis. Methods: Here, we analyzed the cytoprotective mechanism of pituitary adenylate cyclase-activating polypeptide (PACAP)-promoted hepatocellular autophagy in a clinically relevant mouse model of extended hepatic cold storage (4 °C UW solution for 20 h) followed by syngeneic OLT. Results: In contrast to 41.7% of liver graft failure by day 7 post-transplant in control group, PACAP treatment significantly improved graft survival (91.7% by day 14), and promoted autophagy-associated regeneration programs in OLT. In parallel in vitro studies, PACAP-enhanced autophagy ameliorated cellular damage (LDH/ALT levels), and diminished necrosis in H2O2-stressed primary hepatocytes. Interestingly, PACAP not only induced nuclear cAMP response element-binding protein (CREB), but also triggered reprogramming factor Kruppel-like factor 4 (KLF4) expression in IR-stressed OLT. Indeed, CREB inhibition attenuated hepatic autophagy and recreated hepatocellular injury in otherwise PACAP-protected livers. Furthermore, CREB inhibition suppressed PACAP-induced KLF4 expression, whereas KLF4 blockade abolished PACAP-promoted autophagy and neutralized PACAP-mediated hepatoprotection both in vivo and in vitro. Conclusion: Current study documents the essential neural regulation of PACAP-promoted autophagy in hepatocellular homeostasis in OLT, which provides the emerging therapeutic principle to combat hepatic IRI in OLT