31 research outputs found

    CVD diamond coated silicon nitride self-mated systems : tribological behaviour under high loads

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    Friction and wear behaviour of self-mated chemical vapour deposited (CVD) diamond ïŹlms coating silicon nitride ceramics (Si3N4) were investigated in ambient atmosphere. The tribological tests were conducted in a reciprocal motion ball-on-ïŹ‚at type tribometer under applied normal loads up to 80 N (~10 GPa). Several characterisation techniques - including scanning electron microscopy (SEM), atomic force microscopy (AFM) and micro-Raman studies - were used in order to assess the quality, stress state and wear resistance of the coatings. In addition, a novel method is presented to estimate the wear coefficient of the diamond coated ïŹ‚at specimens from AFM and optical microscopy (OM) observations of the wear tracks

    Neurodevelopmental risk factors in schizophrenia

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    The authors review environmental and neurodevelopmental risk factors for schizophrenic disorders, with emphasis on minor physical anomalies, particularly craniofacial anomalies and dermatoglyphic variations. The high prevalence of these anomalies among schizophrenic subjects supports the neurodevelopmental theory of the etiology of schizophrenia, since they suggest either genetically or epigenetically controlled faulty embryonic development of structures of ectodermal origin like brain and skin. This may disturb neurodevelopment that in turn may cause these subjects to be at increased risk for the development of schizophrenia and related disorders. The precise confirmation of this theory, at least in some cases, will provide further understanding of these illnesses, allowing easy and inexpensive identification of subjects at risk and providing guidelines for the development of new pharmacological interventions for early treatment and even for primary prevention of the illness

    Co-expression network of neural-differentiation genes shows specific pattern in schizophrenia

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    Background: Schizophrenia is a neurodevelopmental disorder with genetic and environmental factors contributing to its pathogenesis, although the mechanism is unknown due to the difficulties in accessing diseased tissue during human neurodevelopment. The aim of this study was to find neuronal differentiation genes disrupted in schizophrenia and to evaluate those genes in post-mortem brain tissues from schizophrenia cases and controls. Methods: We analyzed differentially expressed genes (DEG), copy number variation (CNV) and differential methylation in human induced pluripotent stem cells (hiPSC) derived from fibroblasts from one control and one schizophrenia patient and further differentiated into neuron (NPC). Expression of the DEG were analyzed with microarrays of post-mortem brain tissue (frontal cortex) cohort of 29 schizophrenia cases and 30 controls. A Weighted Gene Co-expression Network Analysis (WGCNA) using the DEG was used to detect clusters of co-expressed genes that werenon-conserved between adult cases and controls brain samples. Results: We identified methylation alterations potentially involved with neuronal differentiation in schizophrenia, which displayed an over-representation of genes related to chromatin remodeling complex (adjP = 0.04). We found 228 DEG associated with neuronal differentiation. These genes were involved with metabolic processes, signal transduction, nervous system development, regulation of neurogenesis and neuronal differentiation. Between adult brain samples from cases and controls there were 233 DEG, with only four genes overlapping with the 228 DEG, probably because we compared single cell to tissue bulks and more importantly, the cells were at different stages of development. The comparison of the co-expressed network of the 228 genes in adult brain samples between cases and controls revealed a less conserved module enriched for genes associated with oxidative stress and negative regulation of cell differentiation. Conclusion: This study supports the relevance of using cellular approaches to dissect molecular aspects of neurogenesis with impact in the schizophrenic brain. We showed that, although generated by different approaches, both sets of DEG associated to schizophrenia were involved with neocortical development. The results add to the hypothesis that critical metabolic changes may be occurring during early neurodevelopment influencing faulty development of the brain and potentially contributing to further vulnerability to the illness.We thank the patients, doctors and nurses involved with sample collection and the Stanley Medical Research Institute. This research was supported by either Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq #17/2008) and Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ). MM (CNPq 304429/2014-7), ACT (FAPESP 2014/00041-1), LL (CAPES 10682/13-9) HV (CAPES) and BP (PPSUS 137270) were supported by their fellowshipsinfo:eu-repo/semantics/publishedVersio

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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    Approaches in biotechnological applications of natural polymers

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    Natural polymers, such as gums and mucilage, are biocompatible, cheap, easily available and non-toxic materials of native origin. These polymers are increasingly preferred over synthetic materials for industrial applications due to their intrinsic properties, as well as they are considered alternative sources of raw materials since they present characteristics of sustainability, biodegradability and biosafety. As definition, gums and mucilages are polysaccharides or complex carbohydrates consisting of one or more monosaccharides or their derivatives linked in bewildering variety of linkages and structures. Natural gums are considered polysaccharides naturally occurring in varieties of plant seeds and exudates, tree or shrub exudates, seaweed extracts, fungi, bacteria, and animal sources. Water-soluble gums, also known as hydrocolloids, are considered exudates and are pathological products; therefore, they do not form a part of cell wall. On the other hand, mucilages are part of cell and physiological products. It is important to highlight that gums represent the largest amounts of polymer materials derived from plants. Gums have enormously large and broad applications in both food and non-food industries, being commonly used as thickening, binding, emulsifying, suspending, stabilizing agents and matrices for drug release in pharmaceutical and cosmetic industries. In the food industry, their gelling properties and the ability to mold edible films and coatings are extensively studied. The use of gums depends on the intrinsic properties that they provide, often at costs below those of synthetic polymers. For upgrading the value of gums, they are being processed into various forms, including the most recent nanomaterials, for various biotechnological applications. Thus, the main natural polymers including galactomannans, cellulose, chitin, agar, carrageenan, alginate, cashew gum, pectin and starch, in addition to the current researches about them are reviewed in this article.. }To the Conselho Nacional de Desenvolvimento Cientfíico e Tecnológico (CNPq) for fellowships (LCBBC and MGCC) and the Coordenação de Aperfeiçoamento de Pessoal de Nvíel Superior (CAPES) (PBSA). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and COMPETE 2020 (POCI-01-0145-FEDER-006684) (JAT)

    The etiology of schizophrenia and the origin of language: overview of a theory.

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    Schizophrenia is present in all human populations with approximately the same incidence. Why does such illness persist given that it is associated with a reproductive disadvantage? What is the balancing advantage? A possible explanation is linked to human language. According to this hypothesis schizophrenia occurs as a manifestation of genetic diversity associated with language--the function by which Homo sapiens has separated from other primate species. Language originated by a genetic mutation that allowed the cerebral hemispheres to develop with a degree of specialization (or lateralization) reflected in cerebral asymmetries. Individuals with schizophrenia show lesser structural and functional brain asymmetries than the population as a whole, and this finding can be interpreted as a delay, or failure in, establishing hemispheric dominance for language. We review recent evidence supporting this theory

    The etiology of schizophrenia and the origin of language: overview of a theory.

    No full text
    Schizophrenia is present in all human populations with approximately the same incidence. Why does such illness persist given that it is associated with a reproductive disadvantage? What is the balancing advantage? A possible explanation is linked to human language. According to this hypothesis schizophrenia occurs as a manifestation of genetic diversity associated with language--the function by which Homo sapiens has separated from other primate species. Language originated by a genetic mutation that allowed the cerebral hemispheres to develop with a degree of specialization (or lateralization) reflected in cerebral asymmetries. Individuals with schizophrenia show lesser structural and functional brain asymmetries than the population as a whole, and this finding can be interpreted as a delay, or failure in, establishing hemispheric dominance for language. We review recent evidence supporting this theory

    Long-acting injectable risperidone in partially adherent and nonadherent patients with schizophrenia

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    Mário Rodrigues Louzã1, Helio Elkis1, Sandra Ruschel2, Irismar Reis de Oliveira3, Rodrigo Affonseca Bressan4, Paulo Belmonte-de-Abreu5, Hamilton Grabowski6, José Carlos Appolinário71Universidade de São Paulo, São Paulo; 2Hospital Mário Kroeff, Rio de Janeiro; 3Universidade Federal da Bahia, Salvador; 4Universidade Federal de São Paulo, São Paulo; 5Universidade Federal do Rio Grande do Sul, Porto Alegre; 6Hospital Bom Retiro, Curitiba; 7Janssen-Cilag Farmaceutica Ltda, São Paulo, BrazilBackground: Long-acting injectable antipsychotics may improve medication adherence, thereby improving overall treatment effectiveness. This study aimed to evaluate the effectiveness, safety, and tolerability of risperidone long-acting injection in schizophrenic patients switched from oral antipsychotic medication.Methods: In a 12-month, multicenter, open-label, noncomparative study, symptomatically stable patients on oral antipsychotic medication with poor treatment adherence during the previous 12 months received intramuscular injections of risperidone long-acting injection (25 mg starting dose) every 2 weeks. The primary endpoint was the change in Positive and Negative Syndrome Scale (PANSS) total score.Results: Of the 60 patients who were screened, 53 received at least one injection (safety population), and 51 provided at least one postbaseline assessment. Mean PANSS total scores improved significantly throughout the study and at endpoint. Significant improvements were also observed in Clinical Global Impression of Severity, Personal and Social Performance, and Drug Attitude Inventory scales. Risperidone long-acting injection was safe and well-tolerated. Severity of movement disorders on the Extrapyramidal Symptom Rating Scale was reduced significantly. The most frequently reported adverse events were insomnia (22.6%), increased prolactin (17.0%), and weight gain (13.2%).Conclusion: Risperidone long-acting injection was associated with significant symptomatic improvements in stable patients with schizophrenia following a switch from previous antipsychotic medications.Keywords: patient compliance, adherence, risperidone, delayed-action preparations, schizophreni
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