177 research outputs found
Immune cells and oxidative stress in the endotoxin tolerance mouse model
Sepsis is a systemic inflammatory response that can lead to tissue damage and death. In order to increase our understanding of sepsis, experimental models are needed that produce relevant immune and inflammatory responses during a septic event. We describe a lipopolysaccharide tolerance mouse model to characterize the cellular and molecular alterations of immune cells during sepsis. The model presents a typical lipopolysaccharide tolerance pattern in which tolerance is related to decreased production and secretion of cytokines after a subsequent exposure to a lethal dose of lipopolysaccharide. The initial lipopolysaccharide exposure also altered the expression patterns of cytokines and was followed by an 8- and a 1.5-fold increase in the T helper 1 and 2 cell subpopulations. Behavioral data indicate a decrease in spontaneous activity and an increase in body temperature following exposure to lipopolysaccharide. In contrast, tolerant animals maintained production of reactive oxygen species and nitric oxide when terminally challenged by cecal ligation and puncture (CLP). Survival study after CLP showed protection in tolerant compared to naive animals. Spleen mass increased in tolerant animals followed by increases of B lymphocytes and subpopulation Th1 cells. An increase in the number of stem cells was found in spleen and bone marrow. We also showed that administration of spleen or bone marrow cells from tolerant to naive animals transfers the acquired resistance status. In conclusion, lipopolysaccharide tolerance is a natural reprogramming of the immune system that increases the number of immune cells, particularly T helper 1 cells, and does not reduce oxidative stress.FAPESPCNP
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Subjectivity in a context of environmental change: opening new dialogues in mental health research
In a period of unstable experimentation with challenges of globalization of associated risks, and disenchantment with ‘enduring injustice’, we bring forward a consideration of subjectivity to the study of environmental change and mental health. We begin by identifying how mainstream climate change and mental health studies are unable to explain the emergent and co-evolutionary pathways of agency. As a means of freeing these studies of their objective dimensions of linear-causation, we argue in favour of a re-positioning of subjectivity within an appreciation of recognition conflicts and beyond the over-deterministic interpretations of power centres—state, market or religion. We draw on one example of scientific research that was conducted in a region undergoing strong environmental, social and cultural changes, in the state of São Paulo/Brazil, with the aim to open mental health research to new dialogues, to which we contribute with the notion of the ‘pluriversal subject’
Immigration Cyber Prisons: Ending the Use of Electronic Ankle Shackles
The call to end immigration detention has garnered strong support in recent years due to a growing public awareness of its devastating impact on the individuals locked away, their families, and entire communities. Throughout the nation, communities, organizers, advocates, and public officials have demanded the shutdown of Immigration and Customs Enforcement (ICE) detention centers, particularly those operated by private prison companies.
However, less attention has been paid to another form of detention that has been insidiously expanding alongside ICE’s brick-and-mortar jails: the Intensive Supervision Assistance Program (ISAP), the primary component of ICE’s so-called “Alternatives to Detention” program. ISAP surveils, monitors, and restricts immigrants by using invasive and evolving forms of technology. Like much of ICE’s sprawling detention system, ISAP is fueled by a multi-billion-dollar contract with the subsidiary of a private prison corporation that profits from detaining and surveilling immigrants. One of the most common and dehumanizing forms of surveillance in ISAP is a GPS enabled ankle monitor that shackles individuals both visibly and invisibly.
This report recommends that ICE immediately wind down ISAP and cease its use of electronic ankle shackles, first by removing them from all individuals currently subject to ISAP. To the extent that ankle shackles continue being used while phasing out ISAP, the administration should mandate ICE to track the data needed to prevent discriminatory practices; provide both a clear written justification and review process when deciding to subject an individual to ankle shackles; and allow those subject to ankle shackles to secure employment, participate in family and community activities, and seek medical treatment. This report also recommends a severance of the link between immigration enforcement and service provision through community-based programs, as well as allocation of government funding for community support and legal representation services.
As the harms of electronic ankle shackling demonstrate, ISAP is by no means an acceptable reform to the existing detention apparatus; rather it is another form of confinement that must be dismantled alongside physical detention. While the coercive and dehumanizing shackling of humans is unacceptable in any form, the data demonstrating the comparable or superior efficacy of more holistic intervention also lay bare the animus and profit motives at the heart of ICE’s shackling regime. Ending shackling is not just good policy; it is an issue of racial, economic, and health justice
Ice sheets as a missing source of silica to the polar oceans
Ice sheets play a more important role in the global silicon cycle than previously appreciated. Input of dissolved and amorphous particulate silica into natural waters stimulates the growth of diatoms. Here we measure dissolved and amorphous silica in Greenland Ice Sheet meltwaters and icebergs, demonstrating the potential for high ice sheet export. Our dissolved and amorphous silica flux is 0.20 (0.06-0.79) Tmol year(-1), ∼50% of the input from Arctic rivers. Amorphous silica comprises >95% of this flux and is highly soluble in sea water, as indicated by a significant increase in dissolved silica across a fjord salinity gradient. Retreating palaeo ice sheets were therefore likely responsible for high dissolved and amorphous silica fluxes into the ocean during the last deglaciation, reaching values of ∼5.5 Tmol year(-1), similar to the estimated export from palaeo rivers. These elevated silica fluxes may explain high diatom productivity observed during the last glacial-interglacial period
Zinc Finger Database (ZiFDB): a repository for information on C2H2 zinc fingers and engineered zinc-finger arrays
Zinc fingers are the most abundant DNA-binding motifs encoded by eukaryotic genomes and one of the best understood DNA-recognition domains. Each zinc finger typically binds a 3-nt target sequence, and it is possible to engineer zinc-finger arrays (ZFAs) that recognize extended DNA sequences by linking together individual zinc fingers. Engineered zinc-finger proteins have proven to be valuable tools for gene regulation and genome modification because they target specific sites in a genome. Here we describe ZiFDB (Zinc Finger Database; http://bindr.gdcb.iastate.edu/ZiFDB), a web-accessible resource that compiles information on individual zinc fingers and engineered ZFAs. To enhance its utility, ZiFDB is linked to the output from ZiFiT—a software package that assists biologists in finding sites within target genes for engineering zinc-finger proteins. For many molecular biologists, ZiFDB will be particularly valuable for determining if a given ZFA (or portion thereof) has previously been constructed and whether or not it has the requisite DNA-binding activity for their experiments. ZiFDB will also be a valuable resource for those scientists interested in better understanding how zinc-finger proteins recognize target DNA
ZiFiT (Zinc Finger Targeter): an updated zinc finger engineering tool
ZiFiT (Zinc Finger Targeter) is a simple and intuitive web-based tool that provides an interface to identify potential binding sites for engineered zinc finger proteins (ZFPs) in user-supplied DNA sequences. In this updated version, ZiFiT identifies potential sites for ZFPs made by both the modular assembly and OPEN engineering methods. In addition, ZiFiT now integrates additional tools and resources including scoring schemes for modular assembly, an interface with the Zinc Finger Database (ZiFDB) of engineered ZFPs, and direct querying of NCBI BLAST servers for identifying potential off-target sites within a host genome. Taken together, these features facilitate design of ZFPs using reagents made available to the academic research community by the Zinc Finger Consortium. ZiFiT is freely available on the web without registration at http://bindr.gdcb.iastate.edu/ZiFiT/
Tailor-Made Zinc-Finger Transcription Factors Activate FLO11 Gene Expression with Phenotypic Consequences in the Yeast Saccharomyces cerevisiae
Cys2His2 zinc fingers are eukaryotic DNA-binding motifs, capable of distinguishing different DNA sequences, and are suitable for engineering artificial transcription factors. In this work, we used the budding yeast Saccharomyces cerevisiae to study the ability of tailor-made zinc finger proteins to activate the expression of the FLO11 gene, with phenotypic consequences. Two three-finger peptides were identified, recognizing sites from the 5′ UTR of the FLO11 gene with nanomolar DNA-binding affinity. The three-finger domains and their combined six-finger motif, recognizing an 18-bp site, were fused to the activation domain of VP16 or VP64. These transcription factor constructs retained their DNA-binding ability, with the six-finger ones being the highest in affinity. However, when expressed in haploid yeast cells, only one three-finger recombinant transcription factor was able to activate the expression of FLO11 efficiently. Unlike in the wild-type, cells with such transcriptional activation displayed invasive growth and biofilm formation, without any requirement for glucose depletion. The VP16 and VP64 domains appeared to act equally well in the activation of FLO11 expression, with comparable effects in phenotypic alteration. We conclude that the functional activity of tailor-made transcription factors in cells is not easily predicted by the in vitro DNA-binding activity
A realist review of mobile phone-based health interventions for non-communicable disease management in sub-Saharan Africa
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