69 research outputs found

    Secondary structures on the friction surface of diamond-like coating

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    Peculiarities of the formation of secondary structures on the surface of a diamond-like coating are studied on the example of a friction contact between a steel ball and a diamond-like coating. The friction surface was examined in various areas; the zone of wear products (the boundary of the friction track) and the original surface outside the friction area. It is shown that secondary structures with a high content of iron, nickel, manganese, chromium, and oxygen are characteristic of areas with the highest wear resistance. Such secondary structures are formed because of the intense interaction of the diamond-like coating with the steel of the ball during dry friction

    Physical Activity Characteristics across GOLD Quadrants Depend on the Questionnaire Used

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    BACKGROUND:The GOLD multidimensional classification of COPD severity combines the exacerbation risk with the symptom experience, for which 3 different questionnaires are permitted. This study investigated differences in physical activity (PA) in the different GOLD quadrants and patient's distribution in relation to the questionnaire used. METHODS:136 COPD patients (58±21% FEV1 predicted, 34F/102M) completed COPD assessment test (CAT), clinical COPD questionnaire (CCQ) and modified Medical Research Council (mMRC) questionnaire. Exacerbation history, spirometry and 6MWD were collected. PA was objectively measured for 2 periods of 1 week, 6 months apart, in 5 European centres; to minimise seasonal and clinical variation the average of these two periods was used for analysis. RESULTS:GOLD quadrants C+D had reduced PA compared with A+B (3824 [2976] vs. 5508 [4671] steps.d-1, p<0.0001). The choice of questionnaire yielded different patient distributions (agreement mMRC-CAT κ = 0.57; CCQ-mMRC κ = 0.71; CCQ-CAT κ = 0.72) with different clinical characteristics. PA was notably lower in patients with an mMRC score ≥2 (3430 [2537] vs. 5443 [3776] steps.d-1, p <0.001) in both the low and high risk quadrants. CONCLUSIONS:Using different questionnaires changes the patient distribution and results in different clinical characteristics. Therefore, standardization of the questionnaire used for classification is critical to allow comparison of different studies using this as an entry criterion. CLINICAL TRIAL REGISTRATION:ClinicalTrials.gov NCT01388218

    Correction: Can health status questionnaires be used as a measure of physical activity in COPD patients? (vol 47, pg 1565, 2016)

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    This article from the March 2015 issue of the European Respiratory Journal was published with an error in the author list. The third author, Corina De Jong, was incorrectly listed as Corina De Jongh. The article has been corrected and republished online

    Physical activity is increased by a 12 week semi-automated telecoaching program in patients with COPD, a multicenter randomized controlled trial

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    Rationale Reduced physical activity (PA) in patients with COPD is associated with a poor prognosis. Increasing PA is a key therapeutic target, but thus far few strategies have been found effective in this patient group. Objectives To investigate the effectiveness of a 12 week semi-automated telecoaching intervention on PA in COPD patients in a multicenter European RCT. Methods 343 patients from 6 centers, encompassing a widespectrum of disease severity, were randomly allocated to either a usual care group (UCG) or a telecoaching intervention group (IG) between June and December 2014. This 12 weeks intervention included an exercise booklet and a step counter providing feedback both directly and via a dedicated smartphone application. The latter provided an individualized daily activity goal (steps) revised weekly and text messages as well as allowing occasional telephone contacts with investigators. Physical activity was measured using accelerometry during 1 week preceding randomization and during week 12. Secondary outcomes included exercise capacity and health status. Analyses were based on modified intention-to-treat. Main results Both groups were comparable at baseline in terms of factors influencing PA. At 12 weeks, the intervention yielded a between group difference of mean, 95% CI [ll-ul] +1469, 95% CI [971 – 1965] steps.day-1 and +10.4, 95% CI [6.1 - 14.7] min.day-1 moderate physical activity; favoring the IG (all p≤0.001). The change in six minute walk distance was significantly different (13.4, 95% CI [3.40 - 23.5]m, p<0.01), favoring the IG. In IG patients an improvement could be observed in the functional state domain of the CCQ (p=0.03), when compared to UCG. Other health status outcomes did not differ. Conclusions The amount and intensity of PA can be significantly increased in COPD patients using a 12 week semi-automated telecoaching intervention including a step counter and an application installed on a smartphone. Trial registration NCT02158065 (clinicaltrials.gov

    Nuevas estrategias para el control de las infecciones clamidiales

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    Chlamydia trachomatis (Ctr) es la causa más frecuente de infecciones de transmisión sexual (ITS). La Organización Mundial de la Salud (OMS) estima que cada año se infectan 131 millones de personas, principalmente jóvenes en edad reproductiva. Ctr provoca en la mujer infecciones agudas como cervicitis, endometritis, salpingitis, que frecuentemente cronifican y generan complicaciones graves como enfermedad inflamatoria pélvica, abortos espontáneos e infertilidad. El recién nacido, al infectarse en el canal del parto, puede desarrollar conjuntivitis y neumonía. En el hombre causa uretritis, prostatitis y epididimitis. Es la causa más frecuente en el mundo de ceguera prevenible de naturaleza infecciosa o tracoma. El Ministerio de Salud de la Nación emitió una alerta epidemiológica en agosto de 2018 por la aparición de linfogranuloma venéreo. La falta de sintomatología dificulta el diagnóstico y el tratamiento; sumado a la falta de una vacuna preventiva para evitar el contagio y la aparición de resistencia a antibióticos. Por lo que se requiere el desarrollo de nuevas herramientas para la prevención y el control de las infecciones clamidiales. Ctr invade las células epiteliales cervicales a través de numerosos receptores, muchos de ellos glicosilados y sobrevive y se multiplica intracelularmente en una vesícula llamada inclusión. En el laboratorio hemos demostrado que las células cervicales inflamadas liberan una proteína unidora de glicanos, galectina 1 (Gal1); y que esta lectina es capaz de unirse a proteínas glicosiladas de la membrana externa de Ctr como MOMP (Major Outer Membrane Protein) y OmcB; y a receptores glicosilados de la célula epitelial cervical como PDGFR y varias integrinas. Demostramos que Gal1 facilita el acercamiento de la bacteria a la membrana plasmática y promueve la invasión celular, al actuar como un puente entre los glicanos bacterianos y eucariotas. Gal1 aumenta no sólo el número de células infectadas sino también el número de inclusiones por célula y el número de bacterias por inclusión. Nuestros resultados muestran que la interferencia de la interacción glicanos bacterianos-Gal1-receptores glicosilados con lactosa, glicanasas como PNGasa F o anticuerpos neutralizantes contra los receptores involucrados es efectiva para reducir el reconocimiento y la unión de Ctr a la superficie celular, disminuyendo la invasión, y en consecuencia la magnitud de la infección clamidial. Hemos comprobado in vivo en un modelo murino de infección genital, que los ratones KO para Gal1 o para enzimas formadoras de N-glicanos complejos son menos susceptibles a la infección clamidial. Se ha descripto que Gal1 favorece la infección por el virus de la inmunodeficiencia humana (VIH) y por Trichomonas vaginalis. Gal1 es uno de los mediadores que se libera en los tejidos inflamados y hemos demostrado que Ctr aumenta su expresión, lo que podría explicar al menos en parte, la mayor susceptibilidad del tejido genital femenino inflamado a la invasión por patógenos y la alta frecuencia de re- y co-infecciones en ITS. Nuestros hallazgos sugieren que la interferencia del puente glicanos bacterianos-Gal1-receptores celulares N-glicosilados podría ser una nueva herramienta preventiva para evitar la invasión celular y lograr el control de las infecciones clamidiales y otras ITS.Fil: Damiani, Maria Elena Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Lujan, Agustin Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Croci Russo, Diego Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Gambarte Tudela, Julian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Losinno, Antonella Denise. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Rabinovich, Gabriel Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaXXI Congreso de la Sociedad de Biología de Rosario; XXXIX Reunión Anual de la Sociedad de Biología de RosarioRosarioArgentinaSociedad de Biología de Rosari

    Validity and responsiveness of the Daily- and Clinical visit-PROactive Physical Activity in COPD (D-PPAC and C-PPAC) instruments

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    Background: The Daily-PROactive and Clinical visit-PROactive Physical Activity (D-PPAC and C-PPAC) instruments in chronic obstructive pulmonary disease (COPD) combines questionnaire with activity monitor data to measure patients' experience of physical activity. Their amount, difficulty and total scores range from 0 (worst) to 100 (best) but require further psychometric evaluation. Objective: To test reliability, validity and responsiveness, and to define minimal important difference (MID), of the D-PPAC and C-PPAC instruments, in a large population of patients with stable COPD from diverse severities, settings and countries. Methods: We used data from seven randomised controlled trials to evaluate D-PPAC and C-PPAC internal consistency and construct validity by sex, age groups, COPD severity, country and language as well as responsiveness to interventions, ability to detect change and MID. Results: We included 1324 patients (mean (SD) age 66 (8) years, forced expiratory volume in 1 s 55 (17)% predicted). Scores covered almost the full range from 0 to 100, showed strong internal consistency after stratification and correlated as a priori hypothesised with dyspnoea, health-related quality of life and exercise capacity. Difficulty scores improved after pharmacological treatment and pulmonary rehabilitation, while amount scores improved after behavioural physical activity interventions. All scores were responsive to changes in self-reported physical activity experience (both worsening and improvement) and to the occurrence of COPD exacerbations during follow-up. The MID was estimated to 6 for amount and difficulty scores and 4 for total score. Conclusions: The D-PPAC and C-PPAC instruments are reliable and valid across diverse COPD populations and responsive to pharmacological and non-pharmacological interventions and changes in clinically relevant variables

    Glioblastomas exploit truncated O-linked glycans for local and distant immune modulation via the macrophage galactose-type lectin

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    Glioblastoma is the most aggressive brain malignancy, for which immunotherapy has failed to prolong survival. Glioblastoma-associated immune infiltrates are dominated by tumor-associated macrophages and microglia (TAMs), which are key mediators of immune suppression and resistance to immunotherapy. We and others demonstrated aberrant expression of glycans in different cancer types. These tumor-associated glycans trigger inhibitory signaling in TAMs through glycan-binding receptors. We investigated the glioblastoma glycocalyx as a tumor-intrinsic immune suppressor. We detected increased expression of both tumor-associated truncated O-linked glycans and their receptor, macrophage galactose-type lectin (MGL), on CD163+ TAMs in glioblastoma patient-derived tumor tissues. In an immunocompetent orthotopic glioma mouse model overexpressing truncated O-linked glycans (MGL ligands), high-dimensional mass cytometry revealed a wide heterogeneity of infiltrating myeloid cells with increased infiltration of PD-L1+ TAMs as well as distant alterations in the bone marrow (BM). Our results demonstrate that glioblastomas exploit cell surface O-linked glycans for local and distant immune modulation.Fil: Dusoswa, Sophie A.. Vrije Universiteit Amsterdam; Países BajosFil: Verhoeff, Jan. Vrije Universiteit Amsterdam; Países BajosFil: Abels, Erik. Vrije Universiteit Amsterdam; Países BajosFil: Mendez Huergo, Santiago Patricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Croci Russo, Diego Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Kuijper, Lisan H.. Vrije Universiteit Amsterdam; Países BajosFil: de Miguel, Elena. Vrije Universiteit Amsterdam; Países BajosFil: Wouters, Valerie M. C. J.. Vrije Universiteit Amsterdam; Países BajosFil: Best, Myron G.. Vrije Universiteit Amsterdam; Países BajosFil: Rodriguez, Ernesto. Vrije Universiteit Amsterdam; Países BajosFil: Cornelissen, Lenneke A.M.. Vrije Universiteit Amsterdam; Países BajosFil: van Vliet, Sandra J.. Vrije Universiteit Amsterdam; Países BajosFil: Wesseling, Pieter. Vrije Universiteit Amsterdam; Países BajosFil: Breakefield, Xandra O.. Vrije Universiteit Amsterdam; Países BajosFil: Noske, David P.. Vrije Universiteit Amsterdam; Países BajosFil: Würdinger, Thomas. Harvard Medical School; Estados UnidosFil: Broekman, Marike L.D.. Harvard Medical School; Estados UnidosFil: Rabinovich, Gabriel Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: van Kooyk, Yvette. Vrije Universiteit Amsterdam; Países BajosFil: Garcia Vallejo, Juan J.. Vrije Universiteit Amsterdam; Países Bajo
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