177 research outputs found
Educación y comunicación del patrimonio. Una mirada al desarrollo del potencial creativo en la infancia
La presente investigación tiene como eje central el estudio sobre el desarrollo del potencial creativo en los niños desde lo particular del museo como escenario de comunicación del patrimonio. Con esta finalidad nos adentramos en las dinámicas comunicativas tanto a nivel institucional como a nivel de la agenda educativa de tres museos de referencia en España: El Museo Nacional de Ciencias Naturales; El Real Jardín Botánico y el CaixaForum de Madrid.Como objetivo general de la investigación nos propusimos evaluar el impacto de los programas públicos y educativos que proyectan los museos objeto de estudio, hacia el público infantil en relación con el desarrollo del potencial creativo en los niños participantes. Los resultados fundamentales obtenidos nos develan un sistema que determina la actividad y su nivel de impacto atendiendo a la interrelación de tres dominios: el dominio cultural, el institucional y elde las prácticas.Palabras clave: infancia, creatividad, potencial creativo, comunicación del patrimonio, educación en museos
The impact of CdSe/ZnS Quantum Dots in cells of Medicago sativa in suspension culture
Abstract
Background: Nanotechnology has the potential to provide agriculture with new tools that may be used in the rapid detection and molecular treatment of diseases and enhancement of plant ability to absorb nutrients, among others. Data on nanoparticle toxicity in plants is largely heterogeneous with a diversity of physicochemical parameters reported, which difficult generalizations. Here a cell biology approach was used to evaluate the impact of Quantum Dots (QDs) nanocrystals on plant cells, including their effect on cell growth, cell viability, oxidative stress and ROS accumulation, besides their cytomobility.
Results: A plant cell suspension culture of Medicago sativa was settled for the assessment of the impact of the addition of mercaptopropanoic acid coated CdSe/ZnS QDs. Cell growth was significantly reduced when 100 mM of mercaptopropanoic acid -QDs was added during the exponential growth phase, with less than 50% of the cells viable 72 hours after mercaptopropanoic acid -QDs addition. They were up taken by Medicago sativa cells and accumulated in the cytoplasm and nucleus as revealed by optical thin confocal imaging. As part of the cellular response to internalization, Medicago sativa cells were found to increase the production of Reactive Oxygen Species (ROS) in a dose and time dependent manner. Using the fluorescent dye H2DCFDA it was observable that mercaptopropanoic acid-QDs concentrations between 5-180 nM led to a progressive and linear increase of ROS
accumulation.
Conclusions: Our results showed that the extent of mercaptopropanoic acid coated CdSe/ZnS QDs cytotoxicity in
plant cells is dependent upon a number of factors including QDs properties, dose and the environmental conditions of administration and that, for Medicago sativa cells, a safe range of 1-5 nM should not be exceeded for biological applications.This work was supported by the project “Development of ultra-sensitive
detection methods and plant nano-vaccines for the fungi Fusarium spp. using nanotechnological devices” Iberian Capacitation Program in Nanotechnologies: Call 2006/2007”
La figura jurídica de la fusión y los sistemas institucionales de protección en el ámbito de las sociedades cooperativas de crédito
El presente trabajo se desarrolla en el ámbito de las sociedades cooperativas de crédito, centrándose más concretamente en las Cajas Rurales a la hora de desarrollar todos aquellos aspectos prácticos en complementación con la teoría aportada al respecto. Pues, partiendo de la legislación actual, y en base a un contexto de reestructuración financiera de las mismas en nuestro país, el presente trabajo no solo pretende dar una visión clara de la naturaleza jurídica y particularidades de las sociedades cooperativas en el Derecho de sociedades como sociedades mercantiles, sino que además, pretende ofrecer un enfoque en particular a las dos principales vías de concentración de las mismas, comparando la figura jurídica de la fusión con la de los Sistemas Institucionales de Protección, y exponiendo, por ende, sus principales caracteres y singularidades desde la perspectiva de las cooperativas de crédito, que serán presentadas de una forma teórico-práctica para aproximar al lector a la realidad que las caracteriz
The impact of CdSe/ZnS Quantum Dots in cells of Medicago sativa in suspension culture
<p>Abstract</p> <p>Background</p> <p>Nanotechnology has the potential to provide agriculture with new tools that may be used in the rapid detection and molecular treatment of diseases and enhancement of plant ability to absorb nutrients, among others. Data on nanoparticle toxicity in plants is largely heterogeneous with a diversity of physicochemical parameters reported, which difficult generalizations. Here a cell biology approach was used to evaluate the impact of Quantum Dots (QDs) nanocrystals on plant cells, including their effect on cell growth, cell viability, oxidative stress and ROS accumulation, besides their cytomobility.</p> <p>Results</p> <p>A plant cell suspension culture of <it>Medicago sativa </it>was settled for the assessment of the impact of the addition of mercaptopropanoic acid coated CdSe/ZnS QDs. Cell growth was significantly reduced when 100 mM of mercaptopropanoic acid -QDs was added during the exponential growth phase, with less than 50% of the cells viable 72 hours after mercaptopropanoic acid -QDs addition. They were up taken by <it>Medicago sativa </it>cells and accumulated in the cytoplasm and nucleus as revealed by optical thin confocal imaging. As part of the cellular response to internalization, <it>Medicago sativa </it>cells were found to increase the production of Reactive Oxygen Species (ROS) in a dose and time dependent manner. Using the fluorescent dye H<sub>2</sub>DCFDA it was observable that mercaptopropanoic acid-QDs concentrations between 5-180 nM led to a progressive and linear increase of ROS accumulation.</p> <p>Conclusions</p> <p>Our results showed that the extent of mercaptopropanoic acid coated CdSe/ZnS QDs cytotoxicity in plant cells is dependent upon a number of factors including QDs properties, dose and the environmental conditions of administration and that, for <it>Medicago sativa </it>cells, a safe range of 1-5 nM should not be exceeded for biological applications.</p
How effectively bonding evolution theory retrieves and visualizes curly arrows: The cycloaddition reaction of cyclic nitrones
In the present work, the electron density flows involved throughout the progress of the
four reaction pathways associated with the intramolecular [3 + 2] cycloaddition of cyclic
nitrones Z-1 and E-1 are analyzed using the bonding evolution theory. The present study
highlights the nonconcerted nature of the processes, which can be described as taking
place in several stages. The first stage consists in the depopulation of the initial C N and
C=C double bonds to render the N lone pair and the corresponding C-N and C-C single
bonds, and these electronic flows initiate the reactions. The C-C and C-O sigma bond
formations take place later on, once the transition states have been overcome. Along the
bridged pathways, the C-C bond formation process precedes the O-C bond formation
event, although, along the fused paths, the O-C bond formation process occurs first and
the formation of the C-C bond is the last electronic flow to take place. Finally, curly
arrow representations accounting for the timing of the electron flows are obtained from
the bonding evolution theory results
Reconstructed human pigmented skin/epidermis models achieve epidermal pigmentation through melanocore transfer
Funding: We thank the Electron Microscopy Facility at the Instituto Gulbenkian de Ciência, the Pathological Anatomy service in the Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG) and the Histology Facility at CEDOC for technical assistance. This project was supported by Fundação para a Ciência e a Tecnologia (FCT), Portugal through FCT Unit iNOVA4Health – UIDB/04462/2020 and UIDP/04462/2020, a programme financially supported by FCT / Ministério da Ciência, Tecnologia e Ensino Superior, through national funds, grant PTDC/BIA-CEL/29765/2017, PhD fellowships 2020.08528.BD (SLV), PD/BD/128164/2016, PD/BD/137442/2018 (MVN) and PD/BD/136905/2018 (JC) and the FCT Investigator Program to DCB (IF/00501/2014/CP1252/CT0001).The skin acts as a barrier to environmental insults and provides many vital functions. One of these is to shield DNA from harmful UV radiation, which is achieved by skin pigmentation arising as melanin is produced and dispersed within the epidermal layer. This is a crucial defence against DNA damage, photo-ageing and skin cancer. The mechanisms and regulation of melanogenesis and melanin transfer involve extensive crosstalk between melanocytes and keratinocytes in the epidermis, as well as fibroblasts in the dermal layer. Although the predominant mechanism of melanin transfer continues to be debated and several plausible models have been proposed, we and others previously provided evidence for a coupled exo/phagocytosis model. Herein, we performed histology and immunohistochemistry analyses and demonstrated that a newly developed full-thickness 3D reconstructed human pigmented skin model and an epidermis-only model exhibit dispersed pigment throughout keratinocytes in the epidermis. Transmission electron microscopy revealed melanocores between melanocytes and keratinocytes, suggesting that melanin is transferred through coupled exocytosis/phagocytosis of the melanosome core, or melanocore, similar to our previous observations in human skin biopsies. We therefore present evidence that our in vitro models of pigmented human skin show epidermal pigmentation comparable to human skin. These findings have a high value for studies of skin pigmentation mechanisms and pigmentary disorders, whilst reducing the reliance on animal models and human skin biopsies.publishersversionepub_ahead_of_prin
Evaluación de efectividad y seguridad del anticuerpo monoclonal hr3 para el tratamiento de pacientes con tumores gliales de alto grado de malignidad
This clinical trial will have the overall objective of determining the effectiveness and security of the use of nimotuzumab (hR3 humanized monoclonal antibody) in patients with glial tumor grade III and IV. The specific objectives are to evaluate overall survival and antitumor response, determine the progression-free survival and evaluate, in an open population, the events in patients with glial tumors with a high degree of malignancy treated with AcMhR3. Until the trial section, it was determined that the overall survival was higher for patients who received the investigational product as monotherapy. It was greater for those diagnosed with anaplastic astrocitroma than for those who had glioblastoma multiforme; in the latter patients, the survival among patients treated with monotherapy or combination therapy was equivalent. The evaluation of the objective antitumor response allowed to determine that more than half of the patients remained without disease progression to the eighth week of treatment. Progression-free survival showed that 15 patients exceeded the two-month survival, 12 patients six months, 5 patients a year and 12 patients continue the treatment. Adverse events were classified according to intensity and there were 21 of them, including 10 serious ones, six that culminated in the death of the patient, none of them related to product in research but with the base disease.Este ensayo clínico tendrá como objetivo general determinar la efectividad y la seguridad de la administración del nimotuzumab (anticuerpo monoclonal humanizado hR3) en pacientes que padecen tumores gliales grado III y IV y como objetivos específicos evaluar la supervivencia global y la respuesta antitumoral, determinar la supervivencia libre de progresión y evaluar, en población abierta, los eventos en pacientes con tumores gliales con alto grado de malignidad tratados con el AcMhR3. Hasta el momento del corte de estudio se obtuvo que la supervivencia global fue mayor para aquellos pacientes que recibieron el producto en investigación como monoterapia. Fue mayor para los diagnosticados con astrocitroma anaplásico que para los que presentaron glioblastoma multiforme; en estos últimos la sobrevida entre los pacientes tratados con monoterapia o terapia combinada fue equivalente. La evaluación de la respuesta objetiva antitumoral permitió determinar que más de la mitad de los pacientes se mantuviera sin progresión de la enfermedad a la octava semana de tratamiento. La sobrevida libre de progresión mostró que 15 pacientes sobrepasaron los dos meses de sobrevida, 12 enfermos los seis meses, cinco el año y 12 pacientes continúan el tratamiento. Los eventos adversos se clasificaron según la intensidad y se produjeron 21, de ellos 10 graves, seis que culminaron con el fallecimiento del paciente, ninguno de ellos relacionados con el producto de investigación y sí con la enfermedad base
Lack of Aquaporin 3 in bovine erythrocyte membranes correlates with low glycerol permeation
NOTICE: this is the author’s version of a work that was accepted for publication in Biochemical and Biophysical Research Communications. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Biochemical and Biophysical Research Communications. May 2011; 408 (3): 477-481.In general, erythrocytes are highly permeable to water, urea and glycerol. However, expression of aquaporin isoforms in erythrocytes appears to be species characteristic. In the present study, human (hRBC) and bovine (bRBC) erythrocytes were chosen for comparative studies due to their significant difference in membrane glycerol permeability.
Osmotic water permeability (Pf) at 23 ºC was (2.89 ± 0.37) × 10-2 and (5.12 ± 0.61) × 10-2 cm s-1 for human and bovine cells respectively, with similar activation energies for water transport. Glycerol permeability (Pgly) for human ((1.37 ± 0.26) × 10-5 cm s-1) differed in three orders of magnitude from bovine erythrocytes ((5.82 ± 0.37) ×10-8 cm s-1) that also showed higher activation energy for glycerol transport. When compared to human, bovine erythrocytes showed a similar expression pattern of AQP1 glycosylated forms on immunoblot analysis, though in slight higher levels, which could be correlated with the 1.5-fold larger Pf found. However, AQP3 expression was not detectable. Immunofluorescence analysis confirmed the absence of AQP3 expression in bovine erythrocyte membranes.
In conclusion, lack of AQP3 in bovine erythrocytes points to the lipid pathway as responsible for glycerol permeation and explains the low glycerol permeability and high Ea for transport observed in ruminants
Cerebrospinal fluid chitinases as biomarkers for Amyotrophic Lateral Sclerosis
© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).Amyotrophic lateral sclerosis (ALS) is a neurodegenerative neuromuscular disease that affects motor neurons controlling voluntary muscles. Survival is usually 2-5 years after onset, and death occurs due to respiratory failure. The identification of biomarkers would be very useful to help in disease diagnosis and for patient stratification based on, e.g., progression rate, with implications in therapeutic trials. Neurofilaments constitute already-promising markers for ALS and, recently, chitinases have emerged as novel marker targets for the disease. Here, we investigated cerebrospinal fluid (CSF) chitinases as potential markers for ALS. Chitotriosidase (CHIT1), chitinase-3-like protein 1 (CHI3L1), chitinase-3-like protein 2 (CHI3L2) and the benchmark marker phosphoneurofilament heavy chain (pNFH) were quantified by an enzyme-linked immunosorbent assay (ELISA) from the CSF of 34 ALS patients and 24 control patients with other neurological diseases. CSF was also analyzed by UHPLC-mass spectrometry. All three chitinases, as well as pNFH, were found to correlate with disease progression rate. Furthermore, CHIT1 was elevated in ALS patients with high diagnostic performance, as was pNFH. On the other hand, CHIT1 correlated with forced vital capacity (FVC). The three chitinases correlated with pNFH, indicating a relation between degeneration and neuroinflammation. In conclusion, our results supported the value of CHIT1 as a diagnostic and progression rate biomarker, and its potential as respiratory function marker. The results opened novel perspectives to explore chitinases as biomarkers and their functional relevance in ALS.We acknowledge iNOVA4Health – UIDB/04462/2020 and UIDP/04462/2020, a program financially supported by Fundação para a Ciência e Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior, through national funds.info:eu-repo/semantics/publishedVersio
Infecciones respiratorias agudas: enfermedades que nos afectan
Las infecciones respiratorias agudas (IRA) constituyen uno de los principales problemas de salud, la primera causa de morbilidad y consultas, así como una de las cinco primeras causas de muerte en todas las edades. En nuestro país ha tenido variaciones importantes en los últimos 30 años, de tal forma que nos coloca con cifras similares a los países más desarrollados. En América, sólo Canadá y Estados Unidos nos superan ligeramente en algunos rubros, pero nuestras cifras son muy similares a las de ambos países. Las estrategias generales en la prevención y en el tratamiento de las infecciones respiratorias agudas se basan en: evaluar sistemáticamente los conocimientos existentes acerca de estas infecciones, divulgarlos y aplicarlos, desarrollar una guía nacional para las indicaciones de los antibióticos, aplicar las vacunas existentes, incrementar la inmunización contra el neumococo y el virus influenza, particularmente en grupos de riesgo, desarrollar y evaluar nuevas vacunas contra el Hemophilus influenzae no serotipificable.ABSTRACTAcute respiratory infections (ARI) are one of the major health problems, the leading cause of morbidity and consultations as well as one of the five leading causes of death of all ages. Our country has made important changes in the last 30 years, so that puts us with similar figures to more developed countries. In America, only Canada and the United States beat us slightly in some areas, but our numbers are very similar to those of the two countries. General strategies for the prevention and treatment of acute respiratory infections are based on: systematically evaluate existing knowledge about these infections, disseminate and apply them to develop a national guideline for indications of antibiotics, applying existing vaccines, increasing immunization against pneumococcus and influenza virus, particularly in high-risk groups, develop and evaluate new vaccines against not serotypefiable Hemophilus influenza
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