579 research outputs found

    The role of organizational structure and deviant status in employees’ reactions to and acceptance of workplace deviance

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    Purpose: To examine the role of deviant status (lower vs. higher rank) and organizational structure (vertical vs. horizontal) on individuals’ responses to workplace deviance. Design/methodology/approach: Two studies (N = 472) were designed to examine the role of deviant status and organizational structure in responses to workplace deviance. Study 1 (N = 272) manipulated deviant status and organizational structure. Study 2 (N = 200) also manipulated deviant status but focused on participants’ subjective evaluations of the organizational structure of their workplace. Findings: Study 1 found that participants reported lower job satisfaction and organizational commitment, and higher turnover intentions when they imagined being confronted with deviant behaviors displayed by a manager (vs. by a subordinate), regardless of the type of organizational structure. Study 2 extended this finding by showing that the indirect effect of organizational structure (vertical vs. horizontal) on turnover intention via job satisfaction and organizational commitment was moderated by deviant status: when the deviant’s status was higher, working in a vertical (vs. horizontal) organization was associated with decreased job satisfaction and commitment, which in turn was associated with a higher level of turnover intentions. Originality/value: The findings broaden our understanding of how individuals respond to deviance at the workplace, by simultaneously considering the effects of organizational structure (vertical vs. horizontal) and deviant status (upward vs. downward directions of deviance). Keywords: organizational structure, status, workplace deviance, job satisfaction, organizational commitment, turnover intentio

    Tissue Localization and Extracellular Matrix Degradation by PI, PII and PIII Snake Venom Metalloproteinases: Clues on the Mechanisms of Venom-Induced Hemorrhage

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    20 páginas, 4 figuras, 3 tablas y 7 tablas en material suplementario.Snake venom hemorrhagic metalloproteinases (SVMPs) of the PI, PII and PIII classes were compared in terms of tissue localization and their ability to hydrolyze basement membrane components in vivo, as well as by a proteomics analysis of exudates collected in tissue injected with these enzymes. Immunohistochemical analyses of co-localization of these SVMPs with type IV collagen revealed that PII and PIII enzymes co-localized with type IV collagen in capillaries, arterioles and post-capillary venules to a higher extent than PI SVMP, which showed a more widespread distribution in the tissue. The patterns of hydrolysis by these three SVMPs of laminin, type VI collagen and nidogen in vivo greatly differ, whereas the three enzymes showed a similar pattern of degradation of type IV collagen, supporting the concept that hydrolysis of this component is critical for the destabilization of microvessel structure leading to hemorrhage. Proteomic analysis of wound exudate revealed similarities and differences between the action of the three SVMPs. Higher extent of proteolysis was observed for the PI enzyme regarding several extracellular matrix components and fibrinogen, whereas exudates from mice injected with PII and PIII SVMPs had higher amounts of some intracellular proteins. Our results provide novel clues for understanding the mechanisms by which SVMPs induce damage to the microvasculature and generate hemorrhage.This work was performed in partial fulfillment of the requirements for the PhD degree for Cristina Herrera at Universidad de Costa Rica.Peer reviewe

    A Novel, Orally Delivered Antibody Therapy and Its Potential to Prevent Clostridioides difficile Infection in Pre-clinical Models

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    Clostridioides difficile infection (CDI) is a toxin-mediated infection in the gut and a major burden on healthcare facilities worldwide. We rationalized that it would be beneficial to design an antibody therapy that is delivered to, and is active at the site of toxin production, rather than neutralizing the circulating and luminal toxins after significant damage of the layers of the intestines has occurred. Here we describe a highly potent therapeutic, OraCAb, with high antibody titers and a formulation that protects the antibodies from digestion/inactivation in the gastrointestinal tract. The potential of OraCAb to prevent CDI in an in vivo hamster model and an in vitro human colon model was assessed. In the hamster model we optimized the ratio of the antibodies against each of the toxins produced by C. difficile (Toxins A and B). The concentration of immunoglobulins that is effective in a hamster model of CDI was determined. A highly significant difference in animal survival for those given an optimized OraCAb formulation versus an untreated control group was observed. This is the first study testing the effect of oral antibodies for treatment of CDI in an in vitro gut model seeded with a human fecal inoculum. Treatment with OraCAb successfully neutralized toxin production and did not interfere with the colonic microbiota in this model. Also, treatment with a combination of vancomycin and OraCAb prevented simulated CDI recurrence, unlike vancomycin therapy alone. These data demonstrate the efficacy of OraCAb formulation for the treatment of CDI in pre-clinical models

    Identification of a cytokine network sustaining neutrophil and Th17 activation in untreated early rheumatoid arthritis

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    © 2010 Cascão et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Introduction: Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease characterized by sustained synovitis. Recently, several studies have proposed neutrophils and Th17 cells as key players in the onset and perpetuation of this disease. The main goal of this work was to determine whether cytokines driving neutrophil and Th17 activation are dysregulated in very early rheumatoid arthritis patients with less than 6 weeks of disease duration and before treatment (VERA). Methods: Cytokines related to neutrophil and Th17 activation were quantified in the serum of VERA and established RA patients and compared with other very early arthritis (VEA) and healthy controls. Synovial fluid (SF) from RA and osteoarthritis (OA) patients was also analyzed. Results: VERA patients had increased serum levels of cytokines promoting Th17 polarization (IL-1b and IL-6), as well as IL-8 and Th17-derived cytokines (IL-17A and IL-22) known to induce neutrophil-mediated inflammation. In established RA this pattern is more evident within the SF. Early treatment with methotrexate or corticosteroids led to clinical improvement but without an impact on the cytokine pattern. Conclusions: VERA patients already display increased levels of cytokines related with Th17 polarization and neutrophil recruitment and activation, a dysregulation also found in SF of established RA. 0 Thus, our data suggest that a cytokine-milieu favoring Th17 and neutrophil activity is an early event in RA pathogenesis.This work was supported by a grant from Sociedade Portuguesa de Reumatologia/Schering-Plough 2005. RAM and RC were funded by Fundação para a Ciência e a Tecnologia (FCT) SFRH/BD/30247/2006 and SFRH/BD/40513/2007, respectively. MMS-C was funded by Marie Curie Intra-European Fellowship PERG-2008-239422 and a EULAR Young Investigator Award

    Characterization and Evaluation of Layered Bi2WO6 Nanosheets as a New Antibacterial Agent

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    Background: Pathogenic microorganisms are causing increasing cases of mortality and morbidity, along with alarming rates of ineffectiveness as a result of acquired antimicrobial resistance. Bi2WO6 showed good potential to be used as an antibacterial substance when exposed to visible light. This study demonstrates for the first time the dimension-dependent antibacterial activity of layered Bi2WO6 nanosheets. Materials and methods: The synthesized layered Bi2WO6 nanosheets were prepared by the hydrothermal method and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and Raman and Fourier transform infrared spectroscopy (FTIR). Antibacterial and antibiotic-modulation activities were performed in triplicate by the microdilution method associated with visible light irradiation (LEDs). Results: Bi2WO6 nanosheets were effective against all types of bacteria tested, with MIC values of 256 µg/mL against Escherichia coli standard and resistant strains, and 256 µg/mL and 32 µg/mL against Staphylococcus aureus standard and resistant strains, respectively. Two-dimensional (2D) Bi2WO6 nanosheets showed antibacterial efficiency against both strains studied without the presence of light. Conclusions: Layered Bi2WO6 nanosheets revealed dimension-dependent antibacterial activity of the Bi2WO6 system.The authors thank Conselho Nacional de Desenvolvimento Científico e Tecnológico— CNPq, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—CAPES, and Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico—FUNCAP (Proc. BP4-00172-00232.01.00/20 and Proc. PR2-0101-00006.01.00/15) for the financial support. The authors would also like to thank the educational institutions UFCA, URCA, and UNILEÃO for their support during the experiments

    CONHECIMENTOS DE UNIVERSITÁRIOS DA ÁREA DA SAÚDE SOBRE CONTRACEPÇÃO E PREVENÇÃO DE DOENÇAS SEXUALMENTE TRANSMISSÍVEIS

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    Human sexuality is an important component in the individual’s formation. Sexuality has experienced important changes during human history, such as people’s access to information. In this sense we want to investigate the university students’ knowledge in the area of health at the Federal del Ceará University, Colombia regarding behaviors about contraception and STD prevention, since these future professionals will be an important source of information for the population. Data was obtained between May and June 2005 using a questionnaire of 12 objective questions about sexual education, sexual life and knowledge about pregnancy and STD prevention. Regarding information about sex, family, friends and school were the main sources of information. When asked if HIV could be transmitted through oral sex, 87.5% answered correctly, by responding that yes. There is certain knowledge about sexuality among the students. Nevertheless, there is still a lack of preventive knowledge regarding sexual health.La sexualidad humana es un componente importante en la formación del individuo. Sufrió importantes modificaciones a lo largo de la existencia de la vida humana, como la mayor divulgación de informaciones. Buscamos investigar el conocimiento de los universitarios del área de salud de la Universidad Federal del Ceará referente a las conductas de contracepción y prevención de DST, puesto que estas son una importante fuente de información para la población. La colecta de datos tuvo lugar entre mayo y junio de 2005 por medio de un cuestionario objetivo compuesto de 12 preguntas, acerca de la educación sexual, sexualidad y conocimiento en la prevención del embarazo no deseado y de DST. En cuanto a la orientación sexual, la familia, los amigos y la escuela fueron las principales fuentes de información. Preguntados si la transmisión del VIH se produce a través de sexo oral, 87,5% respondió correctamente al afirmar la cuestión como verdadera. Percibimos cierto conocimiento sobre la sexualidad entre los estudiantes, no obstante todavía hay carencias sobre algunos aspectos preventivos de salud sexual.A sexualidade humana é um importante componente na formação do indivíduo. Esta sofreu importantes modificações ao longo da existência da vida humana, como uma maior divulgação de informações. Assim, buscamos investigar o conhecimento de universitários da área da saúde acerca das condutas de contracepção e prevenção de DST, já que estes são importante fonte de informação para a população. A coleta de dados ocorreu entre maio e junho de 2005 por meio de questionário objetivo com 12 questões, abordando dados relacionados à orientação sexual, sexualidade e conhecimento sobre prevenção de DST e gravidez indesejada. Quanto à orientação sexual a família, amigos e a escola foram as principais fontes de informação. Questionados se a transmissão do HIV ocorre através de sexo oral, 87,5% responderam corretamente ao afirmar a questão como verdadeira. Percebemos certo conhecimento sobre a sexualidade entre os universitários, porém ainda há carências sobre alguns aspectos preventivos da saúde sexua

    Antiplasmodial volatile extracts from Cleistopholis patens Engler & Diels and Uvariastrum pierreanum Engl. (Engl. & Diels) (Annonaceae) growing in Cameroon

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    In a search for alternative treatment for malaria, plant-derived essential oils extracted from the stem barks and leaves of Cleistopholis patens and Uvariastrum pierreanum (Annonaceae) were evaluated in vitro for antiplasmodial activity against the W2 strain of Plasmodium falciparum. The oils were obtained from 500 g each of stem barks and leaves, respectively, by hydrodistillation, using a Clevenger-type apparatus with the following yields: 0.23% and 0.19% for C. patens and 0.1% and 0.3% for U. pierreanum (w/w relative to dried material weight). Analysis of 10% (v/v) oil in hexane by gas chromatography and mass spectrometry identified only terpenoids in the oils, with over 81% sesquiterpene hydrocarbons in C. patens extracts and U. pierreanum stem bark oil, while the leaf oil from the latter species was found to contain a majority of monoterpenes. For C. patens, the major components were α-copaene, δ-cadinene, and germacrene D for the stem bark oil and β-caryophyllene, germacrene D, and germacrene B for the leaf oil. The stem bark oil of U. pierreanum was found to contain mainly β-bisabolene and α-bisabolol, while α- and β-pinenes were more abundant in the leaf extract. Concentrations of oils obtained by diluting 1-mg/mL stock solutions were tested against P. falciparum in culture. The oils were active, with IC50 values of 9.19 and 15.19 μg/mL for the stem bark and leaf oils, respectively, of C. patens and 6.08 and 13.96 μg/mL, respectively, for those from U. pierreanum. These results indicate that essential oils may offer a promising alternative for the development of new antimalarials

    Azimuthal anisotropy and correlations at large transverse momenta in p+pp+p and Au+Au collisions at sNN\sqrt{s_{_{NN}}}= 200 GeV

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    Results on high transverse momentum charged particle emission with respect to the reaction plane are presented for Au+Au collisions at sNN\sqrt{s_{_{NN}}}= 200 GeV. Two- and four-particle correlations results are presented as well as a comparison of azimuthal correlations in Au+Au collisions to those in p+pp+p at the same energy. Elliptic anisotropy, v2v_2, is found to reach its maximum at pt3p_t \sim 3 GeV/c, then decrease slowly and remain significant up to pt7p_t\approx 7 -- 10 GeV/c. Stronger suppression is found in the back-to-back high-ptp_t particle correlations for particles emitted out-of-plane compared to those emitted in-plane. The centrality dependence of v2v_2 at intermediate ptp_t is compared to simple models based on jet quenching.Comment: 4 figures. Published version as PRL 93, 252301 (2004

    Azimuthal anisotropy in Au+Au collisions at sqrtsNN = 200 GeV

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    The results from the STAR Collaboration on directed flow (v_1), elliptic flow (v_2), and the fourth harmonic (v_4) in the anisotropic azimuthal distribution of particles from Au+Au collisions at sqrtsNN = 200 GeV are summarized and compared with results from other experiments and theoretical models. Results for identified particles are presented and fit with a Blast Wave model. Different anisotropic flow analysis methods are compared and nonflow effects are extracted from the data. For v_2, scaling with the number of constituent quarks and parton coalescence is discussed. For v_4, scaling with v_2^2 and quark coalescence is discussed.Comment: 26 pages. As accepted by Phys. Rev. C. Text rearranged, figures modified, but data the same. However, in Fig. 35 the hydro calculations are corrected in this version. The data tables are available at http://www.star.bnl.gov/central/publications/ by searching for "flow" and then this pape

    Rapidity and Centrality Dependence of Proton and Anti-proton Production from Au+Au Collisions at sqrt(sNN) = 130GeV

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    We report on the rapidity and centrality dependence of proton and anti-proton transverse mass distributions from Au+Au collisions at sqrt(sNN) = 130GeV as measured by the STAR experiment at RHIC. Our results are from the rapidity and transverse momentum range of |y|<0.5 and 0.35 <p_t<1.00GeV/c. For both protons and anti-protons, transverse mass distributions become more convex from peripheral to central collisions demonstrating characteristics of collective expansion. The measured rapidity distributions and the mean transverse momenta versus rapidity are flat within |y|<0.5. Comparisons of our data with results from model calculations indicate that in order to obtain a consistent picture of the proton(anti-proton) yields and transverse mass distributions the possibility of pre-hadronic collective expansion may have to be taken into account.Comment: 4 pages, 3 figures, 1 table, submitted to PR
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