27 research outputs found

    Soliton structures in a molecular chain model with saturation

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    In the present work, we study, by means of a one-dimensional lattice model, the collective excitations corresponding to intra molecular ones of a chain like proteins. It is shown that such excitations are described by the Nonlinear Schrodinger equation with saturation. The solutions obtained here are the bell solitons, bubbles, kinks and crowdons. Since they belong to different sectors on the parametric space, the bubble condensation could give place to some important changes of face in this kind of nonlinear system. Additionally, it is shown that the limiting velocity of the solitons is the velocity of sound waves corresponding to longitudinal vibrations of molecules.Comment: 12 pages, 4 figure

    Paraneoplastic encephalitis: clinically based approach on diagnosis and management

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    Paraneoplastic neurological syndromes (PNSs) comprise a subset of immune-mediated nervous system diseases triggered by an underlying malignancy. Each syndrome usually shows a distinct clinical presentation and outcome according to the associated neural antibodies. PNSs generally have a subacute onset with rapid progression and severe neurological disability. However, some patients may have hyperacute onset or even show chronic progression mimicking neurodegenerative diseases. Updated diagnostic criteria for PNS have been recently established in order to increase diagnostic specificity and to encourage standardisation of research initiatives related to PNS. Treatment for PNS includes oncological therapy and immunomodulation to halt neurological deterioration although current treatment options are seldom effective in reversing disability. Nevertheless, growing knowledge and better understanding of PNS pathogenesis promise better recognition, earlier diagnosis and novel treatment strategies. Considering that PNSs provide a model of effective anticancer immunity, the impact of these studies will extend far beyond the field of neurology

    Cytokine dynamics and targeted immunotherapies in autoimmune encephalitis

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    Autoimmune encephalitides constitute a diverse group of immune-mediated central nervous system disorders mainly characterized by the presence of antibodies targeting neuronal or glial antigens. Despite the notable contribution of antibody discovery to the understanding of their physiopathology, the specific immune cells and inflammatory mediators involved in autoimmune encephalitis are still poorly defined. However, cytokines have recently emerged as crucial signalling molecules in the pathogenesis of autoimmune encephalitis. Cytokines are biologically active, soluble, low-molecular-weight proteins or glycoproteins involved in a wide variety of physiological functions, including central nervous system development and homeostasis, immune surveillance, as well as proliferation and maturation of immune cells. Since unbalanced cytokine expression is considered a hallmark of many autoimmune central nervous system disorders, their identification and quantification has become an essential element in personalized medicine applied to the field of neuroimmunology. Several studies have explored the cytokine profile of autoimmune encephalitis, but their interpretation and comparison is challenging due to their small sample sizes and extremely high heterogeneity, especially regarding the cytokines analysed, type of sample used, and associated neural antibody. Only the cytokine profile of anti-N-methyl-D-aspartate receptor encephalitis has extensively been investigated, with findings suggesting that, although humoral immunity is the main effector, T cells may also be relevant for the development of this disorder. A better understanding of cytokine dynamics governing neuroinflammation might offer the opportunity of developing new therapeutic strategies against specific immune cells, cytokines, antibodies, or intracellular signalling cascades, therefore leading to better outcomes and preventing undesired side effects of the presently used strategies. In this review, we first summarize the current knowledge about the role of cytokines in the pathogenesis of autoimmune encephalitis, combining theoretical analysis with experimental validations, to assess their suitability as clinical biomarkers. Second, we discuss the potential applicability of the novel targeted immunotherapies in autoimmune encephalitis depending on the immunobiology of the associated antibody, their limitations, as well as the main limitations that should be addressed in future studies

    Bladder cancer index: cross-cultural adaptation into Spanish and psychometric evaluation

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    BACKGROUND: The Bladder Cancer Index (BCI) is so far the only instrument applicable across all bladder cancer patients, independent of tumor infiltration or treatment applied. We developed a Spanish version of the BCI, and assessed its acceptability and metric properties. METHODS: For the adaptation into Spanish we used the forward and back-translation method, expert panels, and cognitive debriefing patient interviews. For the assessment of metric properties we used data from 197 bladder cancer patients from a multi-center prospective study. The Spanish BCI and the SF-36 Health Survey were self-administered before and 12 months after treatment. Reliability was estimated by Cronbach's alpha. Construct validity was assessed through the multi-trait multi-method matrix. The magnitude of change was quantified by effect sizes to assess responsiveness. RESULTS: Reliability coefficients ranged 0.75-0.97. The validity analysis confirmed moderate associations between the BCI function and bother subscales for urinary (r = 0.61) and bowel (r = 0.53) domains; conceptual independence among all BCI domains (r ≤ 0.3); and low correlation coefficients with the SF-36 scores, ranging 0.14-0.48. Among patients reporting global improvement at follow-up, pre-post treatment changes were statistically significant for the urinary domain and urinary bother subscale, with effect sizes of 0.38 and 0.53. CONCLUSIONS: The Spanish BCI is well accepted, reliable, valid, responsive, and similar in performance compared to the original instrument. These findings support its use, both in Spanish and international studies, as a valuable and comprehensive tool for assessing quality of life across a wide range of bladder cancer patients

    Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

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    BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

    SOLITON STRUCTURES IN A MOLECULAR CHAIN MODEL WITH SATURATION

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    In the present work, we study, by means of a one-dimensional lattice model, the collective excitations corresponding to intra molecular ones of a chain like proteins. It is shown that such excitations are described by the nonlinear Schrödinger equation with saturation. The solutions obtained here are the bell solitons, bubbles, kinks and crowdons. Since they belong to different sectors on the parametric space, the bubble condensation could give rise to some important changes of phase in this nonlinear system. Additionally, it is shown that the limiting velocity of the solitons is the velocity of sound waves corresponding to longitudinal vibrations of molecules

    Novelties in Autoimmune and Paraneoplastic Cerebellar Ataxias: Twenty Years of Progresses

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    Major advances in our knowledge concerning autoimmune and paraneoplastic cerebellar ataxias have occurred in the last 20 years. The discovery of several neural antibodies represents an undeniable contribution to this field, especially those serving as good biomarkers of paraneoplastic neurological syndromes and those showing direct pathogenic effects. Yet, many patients still lack detectable or known antibodies, and also many antibodies have only been reported in few patients, which makes it difficult to define in detail their clinical value. Nevertheless, a notable progress has additionally been made in the clinical characterization of patients with the main neural antibodies, which, although typically present with a subacute pancerebellar syndrome, may also show either hyperacute or chronic onsets that complicate the differential diagnoses. However, prodromal and transient features could be useful clues for an early recognition, and extracerebellar involvement may also be highly indicative of the associated antibody. Moreover, important advances in our understanding of the pathogenesis of cerebellar ataxias include the description of antibody effects, especially those targeting cell-surface antigens, and first attempts to isolate antigen-specific T-cells. Furthermore, genetic predisposition seems relevant, although differently involved according to cancer association, with particular HLA observed in non-paraneoplastic cases and genetic abnormalities in the tumor cells in paraneoplastic ones. Finally, immune checkpoint inhibitors used as cancer immunotherapy may rarely induce cerebellar ataxias, but even this undesirable effect may in turn serve to shed some light on their physiopathology. Herein, we review the principal novelties of the last 20 years regarding autoimmune and paraneoplastic cerebellar ataxias

    A chemo-metric approach to assess heavy metal pollution status in a human impacted coastal system

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    Estuaries are among the most threatened coastal environments since they receive several pollutants from riverine discharges, large urban settlements, industries and ports. These human pressures are enhanced in developing countries of South America, such as Argentina, where the biota is at risk due to several pollutants (metals, POPs and microplastics), and therefore, biomonitoring of these areas is highly recommended. However, few studies have achieved this concern and the scientific tools displayed in an integrative way where abiotic and biotic matrices are combined using multiple indices were even less studied. The current study compared metal concentrations (Cd, Cu, Pb, Zn, Mn, Ni, Cr, Fe) in sediments and a resident benthic crab species, Neohelice granulata and the biochemical biomarkers (CAT, GST, H2O2, MT) in this organisms in a salt marsh (SM) and a mudflat (M) in different stations (autumn and spring) of a SW Atlantic estuary (Bahía Blanca estuary, BBE) in Argentina. This area is currently influenced by several industrial and domestic discharges, ports and large scale fisheries. Overall, metals in sediments did not exhibit significant differences between sites and seasons, except for Mn higher in SM during spring. Crabs bioaccumulated more Cu from sediments during autumn than spring for both sites. Except for Cd in M, Mn, Ni and Fe in SM, metals did not exhibit significant differences for sites, but the values tended to increase in autumn. Through geochemical indices, sediments were low to medium polluted with probable adverse biological effects to the biota. Some of the biochemical analyses applied (i.e., IBR) demonstrated high values in the SM during spring with a great contribution of H2O2 and GST. By multivariate analyses (Pearson correlations and PCA), it was possible to observe that the biomarkers induction might be due to natural intrinsic factors such as energetic costs for reproduction and not strictly metallic pollution. But also, it should be considered that during spring, the available organic matter in the estuary is higher and uptakes metals in the SM coming from plants, ultimately incorporated into the body burden of organisms and probably causing biomarkers induction by some correlated metals like Zn, Cu, Mn and Cd.Fil: Truchet, Daniela María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Negro, Carlos Leandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Buzzi, Natalia Sol. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Mora, M. Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Ardusso, Maialen Gisel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Villagran, Diana Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Garcia, Fabian Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Marcovecchio, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaSETAC Latin America 2021 14th Biennial MeetingPensacolaEstados UnidosSociety of Environmental Toxicology and Chemistr
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