421 research outputs found

    The Inositol- 1,4,5=Trisphosphate System Is Involved in Rapid Effects of Aldosterone in Human Mononuclear Leukocytes

    Get PDF
    There is increasing evidence for rapid steroid action on electrolyte transport in human mononuclear leukocytes (HML). In HML, aldosterone stimulates the Na+/H+ antiporter within a few minutes. Because a variety of hormones and growth factors activate the Na+/H+ antiporter via protein kinase C and inositol phospholipids, a possible involvement of inositol-1,4,5-trisphosphate (IP3) in the rapid effects of aldosterone in HML was investigated. The stimulation of IP3 generation was started by the addition of aldosterone, concanavalin A, or other steroids. A significant increase in IP3 levels by aldosterone (1 nmol/L, P < 0.05) was found after 1 min, similar to that found after concanavalin A (25 micrograms/mL). Aldosterone caused a concentration-dependent elevation of IP3 levels, with an apparent EC50 of approximately 0.1 nmol/L. Fludrocortisone stimulated IP3 generation at similar concentrations, whereas a weaker IP3 stimulation by glucocorticoids (hydrocortisone, dexamethasone) occurred at micromolar concentrations only. Canrenone, a potent inhibitor of classical aldosterone action, was not effective up to a concentration of 100 nmol/L. These findings show kinetic and pharmacological similarities with both the functional data on Na+/H+ antiport stimulation by aldosterone and the studies of 125I-aldosterone binding to plasma membranes of HML. Thus, these data are the first to indicate an involvement of the phosphoinositide pathway in the rapid membrane effects of aldosterone

    To handelsskibe pÄ Øresunds bund

    Get PDF
    Fund af skibsvrag kan tit vÊre verdenssensationer, nÄr det f.eks. drejer sig om meget gamle skibe eller skatteskibe. Forfatteren viser i sin artikel, at fund af nyere og ganske almindelige skibsvrag ogsÄ kan vÊre yderst spÊndende, ikke mindst nÄr der Aa dem kan optages genstande, som kan belyse sÞmandens dagligliv og arbejde ombord. Dette er tilfÊldet med et par vrag, som sportsdykkere har fundet nÊr Hven og bjerget flere interessante ting fra

    Protection against Chlamydia Promoted by a Subunit Vaccine (CTH1) Compared with a Primary Intranasal Infection in a Mouse Genital Challenge Model

    Get PDF
    Background: The chlamydial proteins CT443 (OmcB) and CT521 (rl16) have previously been identified as human B and/or T cell targets during a chlamydial infection in humans. Here we compare the protective effector mechanism promoted by a fusion protein composed of CT521 and CT443 (CTH1) with a primary intranasal Chlamydia muridarum infection known to provide high levels of protection against a genital chlamydial challenge. Methodology/Principal Findings: The fusion protein CTH1, adjuvanted with a strong Th1 inducing cationic adjuvant (CAF01), significantly reduced the bacterial shedding compared to a control group in both a C. trachomatis Serovar D and C. muridarum challenge model. The CTH1/CAF01 vaccine was found to induce polyfunctional T cells consisting of TNFa/IL-2 and TNFa/IL-2/IFN-c positive cells and high titers of CTH1 specific IgG2a and IgG1. By depletion experiments the protection in the C. muridarum challenge model was demonstrated to be mediated solely by CD4 + T cells. In comparison, an intranasal infection with C. muridarum induced a T cell response that consisted predominantly of TNFa/IFN-c co-expressing effector CD4 + T cells and an antibody response consisting of C. muridarum specific IgG1, IgG2a but also IgA. This response was associated with a high level of protection against challenge—a protection that was only partially dependent on CD4 + T cells. Furthermore, whereas the antibody response induced by intranasal infection was strongly reactive against the native antigens displayed in the chlamydial elementary body, only low levels of antibodies against this preparation were foun

    A comparison of the relationship between depression, perceived disability, and physical performance in persons with chronic pain

    Full text link
    This study examined the relationships between self‐report of depressive symptoms, perceived disability, and physical performance among 267 persons with chronic pain. Prior research has reported a relationship between depression and disability using self‐report measures. However, self‐report instruments may be prone to biases associated with depression as depressed persons with pain may have an exaggerated negative view of their level of function. In addition, we examined whether the relationship between depression and functional activity was mediated by physiologic effort (as measured by heart rate). The results indicated that self‐report of depressive symptoms (using the Center for Epidemiological Studies‐Depression Scale (CES‐D)) was significantly correlated with self‐report of disability on the Quebec Back Pain Disability Scale (QBPDS) and physical performance on the Progressive Isoinertial Lifting Evaluation (PILE). Regression analyses revealed that depression assessed by the CES‐D significantly contributed to the prediction of QBPDS scores and PILE performance even when controlling for age, gender, site of pain, and pain intensity. The magnitude of the relationships between depression and self‐report and functional activity were similar, suggesting that a self‐report bias associated with depression is not responsible for an observed relationship between depression and disability. Physiologic effort partially mediated the relationship between depression and physical performance. The findings further highlight the importance of depression in the experience of chronic pain.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90095/1/j.ejpain.2007.11.003.pd

    Identification of a Conserved Region of Plasmodium falciparum MSP3 Targeted by Biologically Active Antibodies to Improve Vaccine Design

    Get PDF
    Merozoite surface protein 3 (MSP3) is a target of antibody-dependent cellular inhibition (ADCI), a protective mechanism against Plasmodium falciparum malaria. From the C-terminal half of the molecule, 6 overlapping peptides were chosen to characterize human immune responses. Each peptide defined at least 1 non-crossreactive B cell epitope. Distinct patterns of antibody responses, by level and IgG subclass distribution, were observed in inhabitants of a malaria-endemic area. Antibodies affinity purified toward each peptide differed in their functional capacity to mediate parasite killing in ADCI assays: 3 of 6 overlapping peptides had a major inhibitory effect on parasite growth. This result was confirmed by the passive transfer of anti-MSP3 antibodies in vivo in a P. falciparum mouse model. T helper cell epitopes were identified in each peptide. Antigenicity and functional assays identified a 70-amino acid conserved domain of MSP3 as a target of biologically active antibodies to be included in future vaccine constructs based on MSP

    Assessment of the quality and quantity of naturally induced antibody responses to EBA175RIII-V in Ghanaian children living in two communities with varying malaria transmission patterns

    Get PDF
    Abstract Background Recent global reports on malaria suggest significant decrease in disease severity and an increase in control interventions in many malaria endemic countries, including Ghana. However, a major driving force sustaining malaria transmission in recent times is the asymptomatic carriage of malaria parasites, which can enhance immune responses against parasite antigens. This study determined the prevalence and relative avidities of naturally induced antibodies to EBA175RIII–VLl in asymptomatic children living in two communities with varying malaria transmission patterns. Methods An asexual stage Plasmodium falciparum antigen, EBA175RIII–VLl was expressed in Lactococcus lactis, purified and used in indirect ELISA to measure total and cytophilic IgG concentrations and avidities in children aged between 6 and 12 years. The children were selected from Obom and Abura, communities with perennial and seasonal malaria transmission, respectively. Venous blood samples were collected in July and October 2015 and again in January 2016. The multiplicity of infection and the genetic diversity of EBA175RIII circulating in both sites were also assessed using polymerase chain reaction. Results Asymptomatic parasite carriage in the children from Obom decreased from July (peak season), through October and January, however parasite carriage in children from Abura was bimodal, with the lowest prevalence estimated in October. Antibody concentrations over the course of the study remained stable within each study site however, children living in Obom had significantly higher EBA175RIII–VLl antibody concentrations than children living in Abura (P < 0.05, Mann–Whitney test). Over the course of the study, the relative antibody avidities of EBA175RIII–VLl IgG antibodies were similar within and between the sites. Conclusion Naturally acquired IgG concentrations but not relative antibody avidities to EBA175RIII–V were significantly higher in Obom where malaria transmission is perennial than in Abura, where malaria transmission is seasonal

    MEWS: Real-time Social Media Manipulation Detection and Analysis

    Full text link
    This article presents a beta-version of MEWS (Misinformation Early Warning System). It describes the various aspects of the ingestion, manipulation detection, and graphing algorithms employed to determine--in near real-time--the relationships between social media images as they emerge and spread on social media platforms. By combining these various technologies into a single processing pipeline, MEWS can identify manipulated media items as they arise and identify when these particular items begin trending on individual social media platforms or even across multiple platforms. The emergence of a novel manipulation followed by rapid diffusion of the manipulated content suggests a disinformation campaign
    • 

    corecore