2,272 research outputs found
A Survey of the Orientation Practices of New Teachers in Minnesota and North Dakota Public Schools
Feminism meets self-care in social change work
The trauma literature reveals that anti-violence work can negatively affect anti-violence workers. These effects are different from those of doing general counselling, therapy, and research. The effects include disrupted beliefs about the goodness of people, difficulty trusting others, emotional numbness, psychic drain, spiritual disconnectedness, and loss of meaning and purpose in life. I experienced a negative transformation while participating in feminist social change work, specifically feminist anti-violence work. I decided to investigate this transformation and share my insights. I collected the data from within myself through an intuitive, reflective writing process, then compared and contrasted my experience to relevant literature. I discovered that feminism, or some assumptions about feminism, in addition to the aforementioned stresses of anti-violence work, impacted negatively on my well-being. I suspect some of my assumptions about feminism are shared with other anti-violence workers, and believe these assumptions may be impeding the progress of the collective women’s movement. I propose that anti-violence workers improve their self-care efforts to reduce the negative impact of their work. I recommend self-care include self-reflection directed toward challenging assumptions and questioning beliefs, values, and practices to improve the effectiveness of self-care and social change efforts. I share contradictions between self-care and feminism that I experienced, and discuss how to reconcile the needs of the self and the collective within feminist social change work. I recommend the assumptions and contradictions I discuss be compared and contrasted to the experiences of other women to enhance our understanding of the impact of self-care and feminism in social change
Cayratia clematidea (F.Muell.) Domin
https://thekeep.eiu.edu/herbarium_specimens_byname/19435/thumbnail.jp
Calcium dependent activation of the NF-AT transcription factor by p59fyn
AbstractA reporter gene under the control of a T-cell antigen receptor response element was activated in Jurkat cells by antigen receptor triggering or by a combination of phorbol myristate acetate, which activates protein kinase C, and a calcium ionophore. Both these signals were necessary for expression of the reporter gene. When co-transfected with a construct capable of overexpressing the tyrosine kinase p59fyn, the reporter gene was activated by PMA alone. Thus p59fyn could replace the calcium ionophore but not activation of protein kinase C. The activation by p59fyn plus PMA was blocked by EGTA and by the immunosuppressant drug cyclosporin A
Calcium-dependent cyclosporin A-sensitive activation of the interleukin-2 promoter by p56lck.
T-cell antigen receptor engagement results in suboptimal activation of protein kinase C and a prolonged increase in intracellular free calcium concentration. These signals, in combination with stimulation via accessory molecules usually supplied by the antigen presenting cell, activate expression of interleukin-2 (IL-2) and initiate autocrine growth. The lymphocyte-specific tyrosine kinase p56lck is physically associated with CD4 and is brought into close proximity of the intracellular domain of the antigen receptor by CD4 recognition of the major histocompatibility complex during antigen presentation. p56lck activation enhances and may be essential for antigen receptor signaling. We report that a constitutively active form of p56lck delivers a signal which contributes to IL-2 promoter activation. The signal substituted for a calcium-mobilizing signal in a Jurkat cell model of T-cell activation. The activation was sensitive to EGTA and cyclosporin A, indicating that p56lck functions at an early stage of the calcium-mediated pathway. The transcription factor NF-AT mediated, at least in part, the p56lck activation of IL-2 expression. In addition, activated p56lck synergized with constitutively active p21Ha-ras, which can replace protein kinase C activation, resulting in activation of NF-AT in the absence of external signals
ras protein activity is essential for T-cell antigen receptor signal transduction.
In a Jurkat cell model of T-cell activation an interleukin-2 promoter/reporter gene construct was activated by antigen receptor agonism in combination with the lymphokine interleukin-1. Antigen receptor signals could be mimicked by suboptimal activation of protein kinase C (PKC) with phorbol esters in combination with calcium mobilization by an ionophore. In cotransfection experiments, oncogenic rats obviated the need for PKC stimulation but did not replace either the calcium signal or interleukin-1. Activated ras expression also replaced the requirement for PKC stimulation in activation of the T-cell transcription factor NF-AT. A dominant inhibitory ras mutant specifically blocked antigen receptor agonism, indicating that ras activity is required for antigen receptor signaling. In addition, an inhibitor of PKC blocked both activated ras and phorbol ester stimulation, suggesting a role for ras upstream of PKC
Interleukin-2 promoter activation in T-cells expressing activated Ha-ras.
Antigen triggering of the T-cell receptor results in an accumulation of activated GTP-bound p21ras protein. To assess the role of ras protein in T-cell activation we have cotransfected the murine thymoma line EL4 with a construct capable of expressing a constitutively active, oncogenic form of Ha-ras and a reporter construct containing the human interleukin-2 promoter fused upstream of the bacterial gene for chloramphenicol acetyltransferase. We show that the ras oncoprotein contributes to interleukin-2 promoter activation. Its pattern of synergism with a calcium ionophore or the lymphokine interleukin-1 indicates that it replaces a signal mediated by protein kinase C. Interleukin-2 promoter activity in the presence of ras oncoprotein was inhibited by H7, a potent inhibitor of protein kinase C, but not by HA1004, an inhibitor of cyclic nucleotide-dependent kinase, suggesting that protein kinase C mediates the ras effect. In addition, we show that in these cells, expression of activated ras results in activation of a synthetic promoter containing several copies of an NF kappa B binding site
Helicobacter pylori toxin VacA is transferred to host cells via a novel contact-dependent mechanism.
Summary Helicobacter pylori is the causative agent of peptic ulcer disease. A major virulence factor of H. pylori is VacA, a toxin that causes massive vacuolization of epithelial cell lines in vitro and gastric epithelial erosion in vivo. Although VacA is exported over the outer membrane and is released from the bacteria, a portion of the toxin remains associated with the bacterial surface. We have found surface-associated toxin to be biologically active and spatially organized into distinct toxin-rich domains on the bacterial surface. Upon bacterial contact with host cells, toxin clusters are transferred directly from the bacterial surface to the host cell surface at the bacteria–cell interface, followed by uptake and intoxication. This contact-dependent transfer of VacA represents a cost-efficient route for delivery of VacA and potentially other bacterial effector molecules to target cells
Cyclosporin A blocks calcium-dependent pathways of gene activation
We have used an interleukin-2 (IL-2) promoter-CAT fusion gene to study activation of IL-2 gene expression by IL-1, phytohemagglutinin (PHA), phorbol myristate acetate (PMA), and calcium ionophore in the murine thymoma line EL4 and the human lymphoma line Jurkat. The two cell lines respond differently to combinations of these stimuli. IL-1 in combination with suboptimal concentration of PMA induced chloramphenicol acetyltransferase (CAT) activity in EL4. In Jurkat cells, IL-1 failed to synergize with PMA or PHA. Cotransfection with the IL-2/CAT gene and a construct capable of expressing murine T-cell type IL-1 receptors converted Jurkat cells to IL-1 responsiveness. IL-1 in combination with PHA but not with PMA resulted in induction of CAT activity in these cells. Induction of IL-2/CAT activity by all stimuli in both cell lines was blocked by the presence of EGTA in the culture medium. EGTA did not inhibit IL-1/PMA activation of an SV40 early promoter-CAT fusion gene in either EL4 or Jurkat cells; therefore, calcium was not required for IL-1 or PMA signal transduction. Jurkat cells were shown to differ from EL4 in their requirement for calcium mobilization. Two different calcium-dependent pathways of gene activation were distinguished, both of which were blocked by the immunosuppressive drug cyclosporin A
Pultenaea williamsii (Fabaceae: Mirbelieae), a new species endemic to the New England Tableland Bioregion of New South Wales
Pultenaea williamsii I.Telford, Clugston & R.L.Barrett (Fabaceae, Faboideae, Mirbelieae), endemic to the New England Bioregion, New South Wales, Australia, is described as new, segregated from the P. flexilis–P. juniperina–P. blakelyi species assemblage. Its distribution is mapped, and habitat and conservation status discussed
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