Search results for " communication"
showing 10 items of 4937 documents
Analysis of parathyroid graft rejection suggests alloantigen-specific production of nitric oxide by iNOS-positive intragraft macrophages
2009
Abstract Background During acute rejection of organ or tissue allografts T cells and macrophages are dominant infiltrating cells. CD4-positive T cells are important for the induction of allograft rejection and macrophages are important effector cells mediating cytotoxicity via production of nitric oxide (NO) by the inducible NO-synthase (iNOS). In the present study we analysed whether the destruction of primarily nonvascularised parathyroid allografts is also mediated by iNOS-positive macrophages. Methods Hypocalcaemic Lewis rats received parathyroid isografts (from Lewis donors) and allografts (from Wistar Furth donors), respectively, under the kidney capsule. Levels of serum calcium above…
The Regulatory T Cell Family: Distinct Subsets and their Interrelations
2003
The immune system, a highly effective and dynamic cellular network, protects a host from pathogens. Therefore, the immune system must distinguish self from nonself structures, but also between harmful and innocuous foreign Ags to prevent nonessential and self-destructive immune responses. The
Chemokines enhance immunity by guiding naive CD8+ T cells to sites of CD4+ T cell-dendritic cell interaction.
2005
CD8+ T cells have a crucial role in resistance to pathogens and can kill malignant cells; however, some critical functions of these lymphocytes depend on helper activity provided by a distinct population of CD4+ T cells. Cooperation between these lymphocyte subsets involves recognition of antigens co-presented by the same dendritic cell, but the frequencies of such antigen-bearing cells early in an infection and of the relevant naive T cells are both low. This suggests that an active mechanism facilitates the necessary cell-cell associations. Here we demonstrate that after immunization but before antigen recognition, naive CD8+ T cells in immunogen-draining lymph nodes upregulate the chemok…
Autocrine transforming growth factor- from chronic lymphocytic leukemia-β cells interferes with proliferative T cell signals
1999
Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of noncycling B cells in lymphatic and extralymphatic tissues. In the present study we investigated the possible contribution of TGF-beta, as secreted by CLL-B cells, on this low proliferative state. CLL-B cells were shown to express TGF-beta RNA and to release bioactive TGF-beta into culture supernatants. Antibody neutralization of endogenously secreted TGF-beta increased the proliferation of CLL-B cells as cultured in the presence of IL-2 or IL-4 or in direct contact with activated CD4+ T cells. In these culture systems, addition of exogenous TGF-beta downregulated basal and cytokineinduced proliferation of CLL-B cell…
Dendritic Cells Lose Ability to Present Protein Antigen after Stimulating Antigen-Specific T Cell Responses, despite Upregulation of MHC Class II Exp…
2000
Abstract Immature dendritic cells (DC) take up, process and present protein antigens; mature DC are specialized for stimulating primary T cell responses with increased expression of MHC class II and co-stimulatory molecules, but are incapable of processing and presenting soluble protein. The current study examined whether maturation of DC is triggered by T cell recognition of antigens presented by immature DC. Human DC derived from CD34+ progenitor cells by culture with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-6 (IL-6) in serum-free medium could prime naive CD4+ T cells to keyhole limpet hemocyanin (KLH) and ovalbumin (OVA). The cultured DC retained the abil…
Crisis management in social media : maintaining the organizational image
2017
The field of crisis communication has faced major changes since the expansion of internet and social media platforms. The difficulty of using social media platforms to or-ganizations’ own advantage in crisis situations has become a recent topic of discussion amongst professionals. The image of an organization provides them competitive advantage in multiple fields, so it is vital to manage these situations so the image remains positive with stakeholders. This thesis aims to provide insights for organizations on how to utilize social media in their crisis communication. 11 Finnish companies with crisis situations during the year 2016 were identified and the data was retrieved from social medi…
Attitude measurement by artificial vision
2005
The recent development of light and low-cost airborne platforms (microlight, drones, kites, balloons,...) has led to the need for simple and low-cost devices allowing attitude measurement with respect to a reference horizon of the platform itself or of an embedded setting. A theoretical study of the conditions for measuring attitude angles from artificial vision is proposed and an original practical algorithm allowing these measurements to be performed in real time is described. An implementation in a CMOS retina circuit is also presented. These points are illustrated by experiments confirming the feasibility of the device.
Employees' perceptions of relational communication in full-time remote work in the public sector.
2021
The global COVID-19 pandemic has led to numerous changes in society. This paper aims to understand how the abrupt transfer to remote work is reflected in employees' perceptions of relational communication at their work. Our research question is as follows: What kinds of perceptions and profiles regarding relational communication can be found among full-time remote workers? A sample of 1, 091 Finnish public sector employees with virtually no previous experience in remote work completed an open-ended survey during the first wave of the pandemic. The findings present 17 aspects of relational communication that the respondents mentioned as having changed because of moving to remote work. These …
TCP Performance in Mobile Ad hoc Networks
2013
International audience; In this paper, we present a survey of TCP (Transmission Control Protocol) protocol for better performance in the MANET (Mobile Ad Hoc Network). After a short presentation of the main features of TCP, we give the most important problems from which TCP suffer in MANET. We present after that some approaches proposed in the literature in order to improve its performance. Our paper contains also a performance evaluation of TCP NewReno and TCP Vegas transport protocols under AODV and DSR routing protocols. The simulations are conducted under varying conditions of number of TCP connections, number of nodes and mobility.
Interleukin-30 feeds breast cancer stem cells via CXCL10 and IL23 autocrine loops and shapes immune contexture and host outcome
2021
BackgroundBreast cancer (BC) progression to metastatic disease is the leading cause of death in women worldwide. Metastasis is driven by cancer stem cells (CSCs) and signals from their microenvironment. Interleukin (IL) 30 promotes BC progression, and its expression correlates with disease recurrence and mortality. Whether it acts by regulating BCSCs is unknown and could have significant therapeutic implications.MethodsHuman (h) and murine (m) BCSCs were tested for their production of and response to IL30 by using flow cytometry, confocal microscopy, proliferation and sphere-formation assays, and PCR array. Immunocompetent mice were used to investigate the role of BCSC-derived IL30 on tumor…