564 research outputs found

    Microplastics and nanoplastics in haemodialysis waters: Emerging threats to be in our radar

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    Microplastics are present in the environment, in drinking water, in human blood and there is evidence of nanoplastics in tap water. The objective of this work was to analyze the possibility of hemodialysis patients being contaminated by micro and nanoplastics (MNPs) during dialysis treatment. The motivation for this investigation is the fact that hemodialysis patients use about 300–600 L of drinking water per week, which may be contaminated by MNPs. A literature review, a field investigation in a London hospital and an estimation of MNPs intake in patients were carried out. The results showed potential points of risk of contamination of patients by MNPs in hemodialysis. It was also estimated that for a filtration efficiency of 99 % for MNPs, the amount of microplastics that can penetrate the kidneys of patients is 0.0021–3768 particles/week. The assessment concludes that hemodialysis patients are at high risk of MNP contamination

    Transmutations and spectral parameter power series in eigenvalue problems

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    We give an overview of recent developments in Sturm-Liouville theory concerning operators of transmutation (transformation) and spectral parameter power series (SPPS). The possibility to write down the dispersion (characteristic) equations corresponding to a variety of spectral problems related to Sturm-Liouville equations in an analytic form is an attractive feature of the SPPS method. It is based on a computation of certain systems of recursive integrals. Considered as families of functions these systems are complete in the L2L_{2}-space and result to be the images of the nonnegative integer powers of the independent variable under the action of a corresponding transmutation operator. This recently revealed property of the Delsarte transmutations opens the way to apply the transmutation operator even when its integral kernel is unknown and gives the possibility to obtain further interesting properties concerning the Darboux transformed Schr\"{o}dinger operators. We introduce the systems of recursive integrals and the SPPS approach, explain some of its applications to spectral problems with numerical illustrations, give the definition and basic properties of transmutation operators, introduce a parametrized family of transmutation operators, study their mapping properties and construct the transmutation operators for Darboux transformed Schr\"{o}dinger operators.Comment: 30 pages, 4 figures. arXiv admin note: text overlap with arXiv:1111.444

    Multimode quantum interference of photons in multiport integrated devices

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    We report the first demonstration of quantum interference in multimode interference (MMI) devices and a new complete characterization technique that can be applied to any photonic device that removes the need for phase stable measurements. MMI devices provide a compact and robust realization of NxM optical circuits, which will dramatically reduce the complexity and increase the functionality of future generations of quantum photonic circuits

    Expression of a barley cystatin gene in maize enhances resistance against phytophagous mites by altering their cysteine-proteases

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    Phytocystatins are inhibitors of cysteine-proteases from plants putatively involved in plant defence based on their capability of inhibit heterologous enzymes. We have previously characterised the whole cystatin gene family members from barley (HvCPI-1 to HvCPI-13). The aim of this study was to assess the effects of barley cystatins on two phytophagous spider mites, Tetranychus urticae and Brevipalpus chilensis. The determination of proteolytic activity profile in both mite species showed the presence of the cysteine-proteases, putative targets of cystatins, among other enzymatic activities. All barley cystatins, except HvCPI-1 and HvCPI-7, inhibited in vitro mite cathepsin L- and/or cathepsin B-like activities, HvCPI-6 being the strongest inhibitor for both mite species. Transgenic maize plants expressing HvCPI-6 protein were generated and the functional integrity of the cystatin transgene was confirmed by in vitro inhibitory effect observed against T. urticae and B. chilensis protein extracts. Feeding experiments impaired on transgenic lines performed with T. urticae impaired mite development and reproductive performance. Besides, a significant reduction of cathepsin L-like and/or cathepsin B-like activities was observed when the spider mite fed on maize plants expressing HvCPI-6 cystatin. These findings reveal the potential of barley cystatins as acaricide proteins to protect plants against two important mite pests

    Novel Machado-Joseph disease-modifying genes and pathways identified by whole-exome sequencing

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    Machado-Joseph disease (MJD/SCA3) is a neurodegenerative polyglutamine disorder exhibiting a wide spectrum of phenotypes. The abnormal size of the (CAG)n at ATXN3 explains ~55% of the age at onset variance, suggesting the involvement of other factors, namely genetic modifiers, whose identification remains limited. Our aim was to find novel genetic modifiers, analyse their epistatic effects and identify disease-modifying pathways contributing to MJD variable expressivity. We performed whole-exome sequencing in a discovery sample of four age at onset-concordant and four discordant first-degree relative pairs of Azorean patients, to identify candidate variants which genotypes differed for each discordant pair but were shared in each concordant pair. Variants identified by this approach were then tested in an independent multi-origin cohort of 282 MJD patients. Whole-exome sequencing identified 233 candidate variants, from which 82 variants in 53 genes were prioritized for downstream analysis. Eighteen disease-modifying pathways were identified; two of the most enriched pathways were relevant for the nervous system, namely the neuregulin signaling and the agrin interactions at neuromuscular junction. Variants at PARD3, NFKB1, CHD5, ACTG1, CFAP57, DLGAP2, ITGB1, DIDO1 and CERS4 modulate age at onset in MJD, with those identified in CFAP57, ACTG1 and DIDO1 showing consistent effects across cohorts of different geographical origins. Network analyses of the nine novel MJD modifiers highlighted several important molecular interactions, including genes/proteins previously related with MJD pathogenesis, namely between ACTG1/APOE and VCP/ITGB1. We describe novel pathways, modifiers, and their interaction partners, providing a broad molecular portrait of age at onset modulation to be further exploited as new disease-modifying targets for MJD and related diseases

    Representações sociais sobre hipertensão arterial e o cuidado: o discurso do sujeito coletivo

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    OBJETIVO: Analisar as representações sociais da equipe de saúde sobre a hipertensão arterial e a maneira como desenvolvem os cuidados específicos aos hipertensos. MÉTODOS: Utilizou-se a entrevista semiestruturada com 21 profissionais de saúde que atuavam em Unidades Básicas de Saúde, a técnica do discurso do sujeito coletivo para organização dos dados e interpretação pela teoria das representações sociais. RESULTADOS: As representações dos profissionais revelaram um distanciamento entre as ações preconizadas pelo programa de controle e as que se realizam nas unidades de saúde. CONCLUSÕES: Os profissionais reconhecem a hipertensão como uma doença grave, com grandes consequências, porém as dificuldades estruturais por parte dos serviços, aliadas à desmotivação do usuário para participação em ações de promoção em saúde, não favorecem um cuidado em saúde voltado para as necessidades dos portadores de hipertensão. Tais resultados indicam a necessidade de ações interdisciplinares na prática assistencial que impactem positivamente na oferta e qualidade dos cuidados.OBJETIVO: Analizar las representaciones sociales del equipo de salud sobre la hipertensión arterial y la manera cómo desarrollan los cuidados específicos a los hipertensos. MÉTODOS: Se utilizó la entrevista semiestructurada con 21 profesionales de salud que actuaban en Unidades Básicas de Salud, la técnica del discurso del sujeto colectivo para la organización de los datos e interpretación por la teoría de las representaciones sociales. RESULTADOS: Las representaciones de los profesionales revelaron un distanciamiento entre las acciones preconizadas por el programa de control y las que se realizan en las unidades de salud. CONCLUSIONES: Los profesionales reconocen a la hipertensión como una enfermedad grave, con grandes consecuencias, sin embargo las dificultades estructurales por parte de los servicos, aliadas a la desmotivación del usuario para participar en acciones de promoción en salud, no favorecen a un cuidado en salud volcado a las necesidades de los portadores de hipertensión. Tales resultados indican la necesidad de acciones interdisciplinaris en la práctica asistencial que impacten positivamente en el ofrecimiento y calidad de los cuidados.OBJECTIVE: To analyze the social representations of the health team about arterial hypertension and the manner that develops specific care with hypertensive patients. METHODS: We used semi-structured interviews with 21 health professionals who worked in the Basic Health Units. The technique of collective subject discourse was used for organization and interpretation of the data, using the theory of social representation. RESULTS: The representations of health professionals showed a gap between the actions recommended by the control program and those taking place in health facilities. CONCLUSIONS: Professionals recognized hypertension as a serious disease, with great consequences, but the structural difficulties for part of the services, together with the user's motivation to participate in activities to promote health, did not favor health care focused on the needs of those suffering with hypertension. These results indicate the need for interdisciplinary actions in care practice that impact positively on the delivery and quality of care
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