264 research outputs found

    Liver failure occurring as a component of exertional heatstroke.

    Get PDF
    An unusual case of an exertional heatstroke in a healthy 25-year-old man is presented. Initially, the patient was deeply comatose and developed severe rhabdomyolysis and massive hepatic necrosis. Subsequently, he received a liver transplant with remarkable improvement in his mental status, although the rhabdomyolysis continued. The patient died 41 days after the transplant due to a complicating infection. Providing that infections can be effectively controlled, liver transplants might be a promising therapeutic alternative for the few patients who survive the initial neurological consequences of this unusual event

    Mitogen-induced stimulation and suppression of erythroid burst promoting activity production by human mononuclear cells

    Full text link
    Exposure of human peripheral blood mononuclear cells or highly enriched monocytes to various plant lectins substantially alters their production of erythroid burst promoting activity (BPA). Neither unstimulated, nor mitogen stimulated, enriched T lymphocytes produced demonstrable BPA. Each of the lectins tested resulted in a different pattern of alteration of BPA production by mononuclear cells. Increasing concentrations of phytohaemagglutinin (PHA) caused a progressive increase in BPA production up to a plateau level at concentrations above 0·25–0·5 Μ1/ml. Concanavalin A (Con A) at concentrations of 0·05–0·1 Μg/ml stimulated BPA production, but Con A concentrations > 1 Μg/ml never augmented BPA production by mononuclear cells. Pokeweed mitogen inhibited BPA production by mononuclear cells in a concentration-dependent manner. Since PHA and Con A can bind to and stimulate both monocytes/macrophages and T lymphocytes, some production of BPA by stimulated T cells in the presence of monocytes cannot be ruled out. Earlier studies demonstrated that T cells augment monocyte production of BPA. Thus, monocyte–T cell interactions, as well as activation of monocytes and perhaps lymphocytes, play an important role in regulation of BPA production in vitro .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73808/1/j.1365-2141.1983.tb01232.x.pd

    Naloxone inhibits immune cell function by suppressing superoxide production through a direct interaction with gp91phox subunit of NADPH oxidase

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Both (-) and (+)-naloxone attenuate inflammation-mediated neurodegeneration by inhibition of microglial activation through superoxide reduction in an opioid receptor-independent manner. Multiple lines of evidence have documented a pivotal role of overactivated NADPH oxidase (NOX2) in inflammation-mediated neurodegeneration. We hypothesized that NOX2 might be a novel action site of naloxone to mediate its anti-inflammatory actions.</p> <p>Methods</p> <p>Inhibition of NOX-2-derived superoxide by (-) and (+)-naloxone was measured in lipopolysaccharide (LPS)-treated midbrain neuron-glia cultures and phorbol myristate acetate (PMA)-stimulated neutrophil membranes by measuring the superoxide dismutase (SOD)-inhibitable reduction of tetrazolium salt (WST-1) or ferricytochrome c. Further, various ligand (<sup>3</sup>H-naloxone) binding assays were performed in wild type and gp91<it><sup>phox-/- </sup></it>neutrophils and transfected COS-7 and HEK293 cells. The translocation of cytosolic subunit p47<it><sup>phox </sup></it>to plasma membrane was assessed by western blot.</p> <p>Results</p> <p>Both (-) and (+)-naloxone equally inhibited LPS- and PMA-induced superoxide production with an IC50 of 1.96 and 2.52 μM, respectively. Competitive binding of <sup>3</sup>H-naloxone with cold (-) and (+)-naloxone in microglia showed equal potency with an IC50 of 2.73 and 1.57 μM, respectively. <sup>3</sup>H-Naloxone binding was elevated in COS-7 and HEK293 cells transfected with gp91<sup><it>phox</it></sup>; in contrast, reduced <sup>3</sup>H-naloxone binding was found in neutrophils deficient in gp91<sup><it>phox </it></sup>or in the presence of a NOX2 inhibitor. The specificity and an increase in binding capacity of <sup>3</sup>H-naloxone were further demonstrated by 1) an immunoprecipitation study using gp91<sup><it>phox </it></sup>antibody, and 2) activation of NOX2 by PMA. Finally, western blot studies showed that naloxone suppressed translocation of the cytosolic subunit p47<sup><it>phox </it></sup>to the membrane, leading to NOX2 inactivation.</p> <p>Conclusions</p> <p>Strong evidence is provided indicating that NOX2 is a non-opioid novel binding site for naloxone, which is critical in mediating its inhibitory effect on microglia overactivation and superoxide production.</p

    FHY1 Mediates Nuclear Import of the Light-Activated Phytochrome A Photoreceptor

    Get PDF
    The phytochrome (phy) family of photoreceptors is of crucial importance throughout the life cycle of higher plants. Light-induced nuclear import is required for most phytochrome responses. Nuclear accumulation of phyA is dependent on two related proteins called FHY1 (Far-red elongated HYpocotyl 1) and FHL (FHY1 Like), with FHY1 playing the predominant function. The transcription of FHY1 and FHL are controlled by FHY3 (Far-red elongated HYpocotyl 3) and FAR1 (FAr-red impaired Response 1), a related pair of transcription factors, which thus indirectly control phyA nuclear accumulation. FHY1 and FHL preferentially interact with the light-activated form of phyA, but the mechanism by which they enable photoreceptor accumulation in the nucleus remains unsolved. Sequence comparison of numerous FHY1-related proteins indicates that only the NLS located at the N-terminus and the phyA-interaction domain located at the C-terminus are conserved. We demonstrate that these two parts of FHY1 are sufficient for FHY1 function. phyA nuclear accumulation is inhibited in the presence of high levels of FHY1 variants unable to enter the nucleus. Furthermore, nuclear accumulation of phyA becomes light- and FHY1-independent when an NLS sequence is fused to phyA, strongly suggesting that FHY1 mediates nuclear import of light-activated phyA. In accordance with this idea, FHY1 and FHY3 become functionally dispensable in seedlings expressing a constitutively nuclear version of phyA. Our data suggest that the mechanism uncovered in Arabidopsis is conserved in higher plants. Moreover, this mechanism allows us to propose a model explaining why phyA needs a specific nuclear import pathway

    Understanding Change in Romantic Relationship Expectations of International Female Students from Turkey

    Get PDF
    In the light of grounded theory, the authors explored change in romantic relationship expectations of international students. Twelve female graduate students from Turkey were interviewed and several themes were identified explaining the presence and absence of change in participants’ attitudes toward romantic relationships. The findings are discussed in relation to acculturation and direction for future research is presented

    A Genome-Wide Association Study Identifies Variants Underlying the Arabidopsis thaliana Shade Avoidance Response

    Get PDF
    Shade avoidance is an ecologically and molecularly well-understood set of plant developmental responses that occur when the ratio of red to far-red light (R∶FR) is reduced as a result of foliar shade. Here, a genome-wide association study (GWAS) in Arabidopsis thaliana was used to identify variants underlying one of these responses: increased hypocotyl elongation. Four hypocotyl phenotypes were included in the study, including height in high R∶FR conditions (simulated sun), height in low R∶FR conditions (simulated shade), and two different indices of the response of height to low R∶FR. GWAS results showed that variation in these traits is controlled by many loci of small to moderate effect. A known PHYC variant contributing to hypocotyl height variation was identified and lists of significantly associated genes were enriched in a priori candidates, suggesting that this GWAS was capable of generating meaningful results. Using metadata such as expression data, GO terms, and other annotation, we were also able to identify variants in candidate de novo genes. Patterns of significance among our four phenotypes allowed us to categorize associations into three groups: those that affected hypocotyl height without influencing shade avoidance, those that affected shade avoidance in a height-dependent fashion, and those that exerted specific control over shade avoidance. This grouping allowed for the development of explicit hypotheses about the genetics underlying shade avoidance variation. Additionally, the response to shade did not exhibit any marked geographic distribution, suggesting that variation in low R∶FR–induced hypocotyl elongation may represent a response to local conditions
    corecore